Merge branch 'release/3.0.0-beta3'

2025-12-17 09:37:02 +00:00 · 2020-09-04 12:45:14 -07:00
parent 0956a13618 1a5db5b5f8
commit 2408ace6c2
49 changed files with 3733 additions and 2873 deletions
--- a/.dockerignore
+++ b/.dockerignore
@@ -6,3 +6,8 @@ inbucket
 inbucket.exe
 swaks-tests
 target
+tags
+tags.*
+ui/dist
+ui/elm-stuff
+ui/node_modules
--- a/.github/workflows/docker-build.yml
+++ b/.github/workflows/docker-build.yml
@@ -0,0 +1,15 @@
+name: Docker Image
+on:
+  push:
+    branches: [ "master", "develop" ]
+  pull_request:
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: docker/build-push-action@v1
+        with:
+          repository: inbucket/inbucket
+          push: false
+          tag_with_ref: true
--- a/.gitignore
+++ b/.gitignore
@@ -21,9 +21,11 @@ _testmain.go

 *.exe

-# vim swp files
+# vim files
 *.swp
 *.swo
+tags
+tags.*

 # Desktop Services Store on macOS
 .DS_Store
@@ -41,6 +43,7 @@ _testmain.go

 # Elm UI
 # elm-package generated files
+/ui/index.html
 /ui/elm-stuff
 /ui/tests/elm-stuff
 # elm-repl generated files
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,4 @@
-sudo: false
+dist: bionic

 env:
  global:
@@ -12,10 +12,13 @@ install:

 jobs:
  include:
-    - go: "1.11.x"
-    - go: "master"
+    - go: "1.14.x"
+    - go: "1.15.x"
    - language: elm
-      elm: "0.19.0"
+      elm: "latest-0.19.1"
+      elm_format: "latest-0.19.1"
+      elm_test: "latest-0.19.1"
+      node_js: "10.16.0"
      install:
        - "cd ui"
        - "npm ci"
@@ -23,9 +26,9 @@ jobs:
        - "elm-format --validate ."
        - "npm run build"
    - stage: deploy
-      go: "1.11.x"
+      go: "1.15.x"
      before_install:
-        - "nvm install 10.13.0"
+        - "nvm install 10.19.0"
      install:
        - "cd ui"
        - "npm ci"
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,22 @@ Change Log
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).

+## [v3.0.0-beta3]
+
+### Added
+- Docker `HEALTHCHECK`
+- Mouse-out delay to improve pop-up menu navigation
+- Support for configurable URL base path with `INBUCKET_WEB_BASEPATH`
+
+### Changed
+- Updated frontend and backend dependencies, Docker image base
+
+### Fixed
+- Improved layout on mobile and wide displays
+- Prevent unexpected input for modal dialogs
+- Allow empty SMTP `MAIL FROM:<>`
+
+
 ## [v3.0.0-beta2]

 ### Added
@@ -212,6 +228,7 @@ No change from beta1.
  specific message.

 [Unreleased]:  https://github.com/inbucket/inbucket/compare/master...develop
+[v3.0.0-beta3]: https://github.com/inbucket/inbucket/compare/v3.0.0-beta2...v3.0.0-beta3
 [v3.0.0-beta2]: https://github.com/inbucket/inbucket/compare/v3.0.0-beta1...v3.0.0-beta2
 [v3.0.0-beta1]: https://github.com/inbucket/inbucket/compare/v2.1.0...v3.0.0-beta1
 [v2.1.0-beta1]: https://github.com/inbucket/inbucket/compare/v2.0.0...v2.1.0-beta1
--- a/24
+++ b/24
@@ -1,22 +1,31 @@
 # Docker build file for Inbucket: https://www.inbucket.org/

-# Build
-FROM golang:1.12-alpine3.10 as builder
-RUN apk add --no-cache --virtual .build-deps git make npm
+# Install build-time dependencies
+FROM golang:1.15-alpine3.12 as builder
+RUN apk add --no-cache --virtual .build-deps g++ git make npm python3
 WORKDIR /build
 COPY . .
 ENV CGO_ENABLED 0
 RUN make clean deps
+WORKDIR /build/ui
+RUN rm -rf dist elm-stuff node_modules
+RUN npm ci
+ADD https://github.com/elm/compiler/releases/download/0.19.1/binary-for-linux-64-bit.gz elm.gz
+RUN gunzip elm.gz && chmod 755 elm && mv elm /usr/bin/
+
+# Build server
+WORKDIR /build
 RUN go build -o inbucket \
  -ldflags "-X 'main.version=$(git describe --tags --always)' -X 'main.date=$(date -Iseconds)'" \
  -v ./cmd/inbucket
+
+# Build frontend
 WORKDIR /build/ui
-RUN rm -rf dist elm-stuff node_modules
-RUN npm i
 RUN npm run build

 # Run in minimal image
-FROM alpine:3.10
+FROM alpine:3.12
+RUN apk --no-cache add tzdata
 WORKDIR /opt/inbucket
 RUN mkdir bin defaults ui
 COPY --from=builder /build/inbucket bin
@@ -36,6 +45,9 @@ ENV INBUCKET_STORAGE_PARAMS path:/storage
 ENV INBUCKET_STORAGE_RETENTIONPERIOD 72h
 ENV INBUCKET_STORAGE_MAILBOXMSGCAP 300

+# Healthcheck
+HEALTHCHECK --interval=5s --timeout=5s --retries=3 CMD /bin/sh -c 'wget localhost:$(echo ${INBUCKET_WEB_ADDR:-0.0.0.0:9000}|cut -d: -f2) -q -O - >/dev/null'
+
 # Ports: SMTP, HTTP, POP3
 EXPOSE 2500 9000 1100

--- a/cmd/inbucket/main.go
+++ b/cmd/inbucket/main.go
@@ -25,6 +25,7 @@ import (
 	"github.com/inbucket/inbucket/pkg/storage"
 	"github.com/inbucket/inbucket/pkg/storage/file"
 	"github.com/inbucket/inbucket/pkg/storage/mem"
+	"github.com/inbucket/inbucket/pkg/stringutil"
 	"github.com/inbucket/inbucket/pkg/webui"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -71,6 +72,7 @@ func main() {
 		config.Usage()
 		return
 	}
+
 	// Process configuration.
 	config.Version = version
 	config.BuildDate = date
@@ -83,6 +85,7 @@ func main() {
 		conf.POP3.Debug = true
 		conf.SMTP.Debug = true
 	}
+
 	// Logger setup.
 	closeLog, err := openLog(conf.LogLevel, *logfile, *logjson)
 	if err != nil {
@@ -90,12 +93,15 @@ func main() {
 		os.Exit(1)
 	}
 	startupLog := log.With().Str("phase", "startup").Logger()
+
 	// Setup signal handler.
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, syscall.SIGTERM, syscall.SIGINT)
+
 	// Initialize logging.
 	startupLog.Info().Str("version", config.Version).Str("buildDate", config.BuildDate).
 		Msg("Inbucket starting")
+
 	// Write pidfile if requested.
 	if *pidfile != "" {
 		pidf, err := os.Create(*pidfile)
@@ -107,6 +113,7 @@ func main() {
 			startupLog.Fatal().Err(err).Str("path", *pidfile).Msg("Failed to close pidfile")
 		}
 	}
+
 	// Configure internal services.
 	rootCtx, rootCancel := context.WithCancel(context.Background())
 	shutdownChan := make(chan bool)
@@ -118,20 +125,26 @@ func main() {
 	msgHub := msghub.New(rootCtx, conf.Web.MonitorHistory)
 	addrPolicy := &policy.Addressing{Config: conf}
 	mmanager := &message.StoreManager{AddrPolicy: addrPolicy, Store: store, Hub: msgHub}
+
 	// Start Retention scanner.
 	retentionScanner := storage.NewRetentionScanner(conf.Storage, store, shutdownChan)
 	retentionScanner.Start()
-	// Start HTTP server.
-	webui.SetupRoutes(web.Router.PathPrefix("/serve/").Subrouter())
-	rest.SetupRoutes(web.Router.PathPrefix("/api/").Subrouter())
+
+	// Configure routes and start HTTP server.
+	prefix := stringutil.MakePathPrefixer(conf.Web.BasePath)
+	webui.SetupRoutes(web.Router.PathPrefix(prefix("/serve/")).Subrouter())
+	rest.SetupRoutes(web.Router.PathPrefix(prefix("/api/")).Subrouter())
 	web.Initialize(conf, shutdownChan, mmanager, msgHub)
 	go web.Start(rootCtx)
+
 	// Start POP3 server.
 	pop3Server := pop3.New(conf.POP3, shutdownChan, store)
 	go pop3Server.Start(rootCtx)
+
 	// Start SMTP server.
 	smtpServer := smtp.NewServer(conf.SMTP, shutdownChan, mmanager, addrPolicy)
 	go smtpServer.Start(rootCtx)
+
 	// Loop forever waiting for signals or shutdown channel.
 signalLoop:
 	for {
@@ -154,6 +167,7 @@ signalLoop:
 			break signalLoop
 		}
 	}
+
 	// Wait for active connections to finish.
 	go timedExit(*pidfile)
 	smtpServer.Drain()
--- a/doc/config.md
+++ b/doc/config.md
@@ -28,6 +28,7 @@ variables it supports:
    INBUCKET_POP3_DOMAIN                inbucket            HELLO domain
    INBUCKET_POP3_TIMEOUT               600s                Idle network timeout
    INBUCKET_WEB_ADDR                   0.0.0.0:9000        Web server IP4 host:port
+    INBUCKET_WEB_BASEPATH                                   Base path prefix for UI and API URLs
    INBUCKET_WEB_UIDIR                  ui/dist             User interface dir
    INBUCKET_WEB_GREETINGFILE           ui/greeting.html    Home page greeting HTML
    INBUCKET_WEB_MONITORVISIBLE         true                Show monitor tab in UI?
@@ -231,7 +232,7 @@ This option is only valid when INBUCKET_SMTP_TLSENABLED is enabled.

 ### TLS Public Certificate File

-`INBUCKET_SMTP_TLSPRIVKEY`
+`INBUCKET_SMTP_TLSCERT`

 Specify the x509 Certificate file to be used for TLS negotiation.
 This option is only valid when INBUCKET_SMTP_TLSENABLED is enabled.
@@ -290,6 +291,24 @@ Inbucket to listen on all available network interfaces.

 - Default: `0.0.0.0:9000`

+### Base Path
+
+`INBUCKET_WEB_BASEPATH`
+
+Base path prefix for UI and API URLs.  This option is used when you wish to
+root all Inbucket URLs to a specific path when placing it behind a
+reverse-proxy.
+
+For example, setting the base path to `prefix` will move:
+- the Inbucket status page from `/status` to `/prefix/status`,
+- Bob's mailbox from `/m/bob` to `/prefix/m/bob`, and
+- the REST API from `/api/v1/*` to `/prefix/api/v1/*`.
+
+*Note:* This setting will not work correctly when running Inbucket via the npm
+development server.
+
+- Default: None
+
 ### UI Directory

 `INBUCKET_WEB_UIDIR`
--- a/etc/dev-start.sh
+++ b/etc/dev-start.sh
@@ -13,6 +13,7 @@ export INBUCKET_WEB_TEMPLATECACHE="false"
 export INBUCKET_WEB_COOKIEAUTHKEY="not-secret"
 export INBUCKET_WEB_UIDIR="ui/dist"
 #export INBUCKET_WEB_MONITORVISIBLE="false"
+#export INBUCKET_WEB_BASEPATH="prefix"
 export INBUCKET_STORAGE_TYPE="file"
 export INBUCKET_STORAGE_PARAMS="path:/tmp/inbucket"
 export INBUCKET_STORAGE_RETENTIONPERIOD="3h"
--- a/etc/docker/docker-run.sh
+++ b/etc/docker/docker-run.sh
@@ -3,7 +3,7 @@
 # description: Launch Inbucket's docker image

 # Docker Image Tag
-IMAGE="jhillyerd/inbucket"
+IMAGE="inbucket/inbucket"

 # Ports exposed on host:
 PORT_HTTP=9000
--- a/go.mod
+++ b/go.mod
@@ -2,20 +2,24 @@ module github.com/inbucket/inbucket

 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/go-test/deep v1.0.2 // indirect
-	github.com/google/subcommands v1.0.1
+	github.com/gogs/chardet v0.0.0-20191104214054-4b6791f73a28 // indirect
+	github.com/google/subcommands v1.2.0
 	github.com/gorilla/css v1.0.0
-	github.com/gorilla/mux v1.7.3
-	github.com/gorilla/websocket v1.4.0
-	github.com/jaytaylor/html2text v0.0.0-20190408195923-01ec452cbe43 // indirect
-	github.com/jhillyerd/enmime v0.6.0
+	github.com/gorilla/mux v1.8.0
+	github.com/gorilla/websocket v1.4.2
+	github.com/jaytaylor/html2text v0.0.0-20200412013138-3577fbdbcff7 // indirect
+	github.com/jhillyerd/enmime v0.8.1
 	github.com/jhillyerd/goldiff v0.1.0
 	github.com/kelseyhightower/envconfig v1.4.0
-	github.com/mattn/go-runewidth v0.0.4 // indirect
-	github.com/microcosm-cc/bluemonday v1.0.2
-	github.com/olekukonko/tablewriter v0.0.1 // indirect
-	github.com/rs/zerolog v1.15.0
-	github.com/stretchr/testify v1.3.0
-	golang.org/x/net v0.0.0-20190724013045-ca1201d0de80
-	golang.org/x/text v0.3.2 // indirect
+	github.com/mattn/go-runewidth v0.0.9 // indirect
+	github.com/microcosm-cc/bluemonday v1.0.4
+	github.com/olekukonko/tablewriter v0.0.4 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/rs/zerolog v1.19.0
+	github.com/stretchr/testify v1.6.1
+	golang.org/x/net v0.0.0-20200822124328-c89045814202
+	golang.org/x/text v0.3.3 // indirect
+	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
 )
+
+go 1.13
--- a/go.sum
+++ b/go.sum
@@ -1,68 +1,89 @@
+github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
+github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
+github.com/cention-sany/utf7 v0.0.0-20170124080048-26cad61bd60a h1:MISbI8sU/PSK/ztvmWKFcI7UGb5/HQT7B+i3a2myKgI=
+github.com/cention-sany/utf7 v0.0.0-20170124080048-26cad61bd60a/go.mod h1:2GxOXOlEPAMFPfp014mK1SWq8G8BN8o7/dfYqJrVGn8=
+github.com/chris-ramon/douceur v0.2.0 h1:IDMEdxlEUUBYBKE4z/mJnFyVXox+MjuEVDJNN27glkU=
+github.com/chris-ramon/douceur v0.2.0/go.mod h1:wDW5xjJdeoMm1mRt4sD4c/LbF/mWdEpRXQKjTR8nIBE=
 github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/go-test/deep v1.0.1 h1:UQhStjbkDClarlmv0am7OXXO4/GaPdCGiUiMTvi28sg=
-github.com/go-test/deep v1.0.1/go.mod h1:wGDj63lr65AM2AQyKZd/NYHGb0R+1RLqB8NKt3aSFNA=
 github.com/go-test/deep v1.0.2 h1:onZX1rnHT3Wv6cqNgYyFOOlgVKJrksuCMCRvJStbMYw=
 github.com/go-test/deep v1.0.2/go.mod h1:wGDj63lr65AM2AQyKZd/NYHGb0R+1RLqB8NKt3aSFNA=
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 github.com/gogs/chardet v0.0.0-20150115103509-2404f7772561/go.mod h1:Pcatq5tYkCW2Q6yrR2VRHlbHpZ/R4/7qyL1TCF7vl14=
-github.com/google/subcommands v1.0.1 h1:/eqq+otEXm5vhfBrbREPCSVQbvofip6kIz+mX5TUH7k=
-github.com/google/subcommands v1.0.1/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
+github.com/gogs/chardet v0.0.0-20191104214054-4b6791f73a28 h1:gBeyun7mySAKWg7Fb0GOcv0upX9bdaZScs8QcRo8mEY=
+github.com/gogs/chardet v0.0.0-20191104214054-4b6791f73a28/go.mod h1:Pcatq5tYkCW2Q6yrR2VRHlbHpZ/R4/7qyL1TCF7vl14=
+github.com/google/subcommands v1.2.0 h1:vWQspBTo2nEqTUFita5/KeEWlUL8kQObDFbub/EN9oE=
+github.com/google/subcommands v1.2.0/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
 github.com/gorilla/css v1.0.0 h1:BQqNyPTi50JCFMTw/b67hByjMVXZRwGha6wxVGkeihY=
 github.com/gorilla/css v1.0.0/go.mod h1:Dn721qIggHpt4+EFCcTLTU/vk5ySda2ReITrtgBl60c=
-github.com/gorilla/mux v1.7.3 h1:gnP5JzjVOuiZD07fKKToCAOjS0yOpj/qPETTXCCS6hw=
-github.com/gorilla/mux v1.7.3/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
-github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
-github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
-github.com/jaytaylor/html2text v0.0.0-20180606194806-57d518f124b0 h1:xqgexXAGQgY3HAjNPSaCqn5Aahbo5TKsmhp8VRfr1iQ=
-github.com/jaytaylor/html2text v0.0.0-20180606194806-57d518f124b0/go.mod h1:CVKlgaMiht+LXvHG173ujK6JUhZXKb2u/BQtjPDIvyk=
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+github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
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 github.com/jaytaylor/html2text v0.0.0-20190408195923-01ec452cbe43 h1:jTkyeF7NZ5oIr0ESmcrpiDgAfoidCBF4F5kJhjtaRwE=
 github.com/jaytaylor/html2text v0.0.0-20190408195923-01ec452cbe43/go.mod h1:CVKlgaMiht+LXvHG173ujK6JUhZXKb2u/BQtjPDIvyk=
-github.com/jhillyerd/enmime v0.6.0 h1:FeypffI/uD1xt+Csd7gfD7mYx1h+qjgGlcI/ko5+LsI=
-github.com/jhillyerd/enmime v0.6.0/go.mod h1:lwWyVhHVBdmzXx3wtRTmpIdNEJyZ85LJuVqZHVK/Rlo=
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-github.com/mattn/go-runewidth v0.0.3 h1:a+kO+98RDGEfo6asOGMmpodZq4FNtnGP54yps8BzLR4=
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-github.com/microcosm-cc/bluemonday v1.0.2 h1:5lPfLTTAvAbtS0VqT+94yOtFnGfUWYyx0+iToC3Os3s=
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-github.com/olekukonko/tablewriter v0.0.0-20180912035003-be2c049b30cc h1:rQ1O4ZLYR2xXHXgBCCfIIGnuZ0lidMQw2S5n1oOv+Wg=
-github.com/olekukonko/tablewriter v0.0.0-20180912035003-be2c049b30cc/go.mod h1:vsDQFd/mU46D+Z4whnwzcISnGGzXWMclvtLoiIKAKIo=
+github.com/mattn/go-runewidth v0.0.7/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
+github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=
+github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
+github.com/microcosm-cc/bluemonday v1.0.4 h1:p0L+CTpo/PLFdkoPcJemLXG+fpMD7pYOoDEq1axMbGg=
+github.com/microcosm-cc/bluemonday v1.0.4/go.mod h1:8iwZnFn2CDDNZ0r6UXhF4xawGvzaqzCRa1n3/lO3W2w=
 github.com/olekukonko/tablewriter v0.0.1 h1:b3iUnf1v+ppJiOfNX4yxxqfWKMQPZR5yoh8urCTFX88=
 github.com/olekukonko/tablewriter v0.0.1/go.mod h1:vsDQFd/mU46D+Z4whnwzcISnGGzXWMclvtLoiIKAKIo=
+github.com/olekukonko/tablewriter v0.0.4 h1:vHD/YYe1Wolo78koG299f7V/VAS08c6IpCLn+Ejf/w8=
+github.com/olekukonko/tablewriter v0.0.4/go.mod h1:zq6QwlOf5SlnkVbMSr5EoBv3636FWnp+qbPhuoO21uA=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
-github.com/rs/zerolog v1.15.0 h1:uPRuwkWF4J6fGsJ2R0Gn2jB1EQiav9k3S6CSdygQJXY=
-github.com/rs/zerolog v1.15.0/go.mod h1:xYTKnLHcpfU2225ny5qZjxnj9NvkumZYjJHlAThCjNc=
+github.com/rs/zerolog v1.19.0 h1:hYz4ZVdUgjXTBUmrkrw55j1nHx68LfOKIQk5IYtyScg=
+github.com/rs/zerolog v1.19.0/go.mod h1:IzD0RJ65iWH0w97OQQebJEvTZYvsCUm9WVLWBQrJRjo=
 github.com/saintfish/chardet v0.0.0-20120816061221-3af4cd4741ca h1:NugYot0LIVPxTvN8n+Kvkn6TrbMyxQiuvKdEwFdR9vI=
 github.com/saintfish/chardet v0.0.0-20120816061221-3af4cd4741ca/go.mod h1:uugorj2VCxiV1x+LzaIdVa9b4S4qGAcH6cbhh4qVxOU=
 github.com/ssor/bom v0.0.0-20170718123548-6386211fdfcf h1:pvbZ0lM0XWPBqUKqFU8cmavspvIl9nulOYwdy6IFRRo=
 github.com/ssor/bom v0.0.0-20170718123548-6386211fdfcf/go.mod h1:RJID2RhlZKId02nZ62WenDCkgHFerpIOmW0iT7GKmXM=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
-github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/zenazn/goji v0.9.0/go.mod h1:7S9M489iMyHBNxwZnk9/EHS098H4/F6TATF2mIxtB1Q=
+github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/net v0.0.0-20181017193950-04a2e542c03f h1:4pRM7zYwpBjCnfA1jRmhItLxYJkaEnsmuAcRtA347DA=
-golang.org/x/net v0.0.0-20181017193950-04a2e542c03f/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20181220203305-927f97764cc3/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
-golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190724013045-ca1201d0de80 h1:Ao/3l156eZf2AW5wK8a7/smtodRU+gha3+BeqJ69lRk=
 golang.org/x/net v0.0.0-20190724013045-ca1201d0de80/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200822124328-c89045814202 h1:VvcQYSHwXgi7W+TpUR6A9g6Up98WAHf3f/ulnJ62IyA=
+golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.org/x/tools v0.0.0-20190425163242-31fd60d6bfdc/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
+golang.org/x/tools v0.0.0-20190828213141-aed303cbaa74/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 h1:tQIYjPdBoyREyB9XMu+nnTclpTYkz2zFM+lzLJFO4gQ=
+gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -96,6 +96,7 @@ type POP3 struct {
 // Web contains the HTTP server configuration.
 type Web struct {
 	Addr           string `required:"true" default:"0.0.0.0:9000" desc:"Web server IP4 host:port"`
+	BasePath       string `default:"" desc:"Base path prefix for UI and API URLs"`
 	UIDir          string `required:"true" default:"ui/dist" desc:"User interface dir"`
 	GreetingFile   string `required:"true" default:"ui/greeting.html" desc:"Home page greeting HTML"`
 	MonitorVisible bool   `required:"true" default:"true" desc:"Show monitor tab in UI?"`
--- a/pkg/server/pop3/handler.go
+++ b/pkg/server/pop3/handler.go
@@ -169,6 +169,7 @@ func (s *Server) startSession(id int, conn net.Conn) {
 				}
 				break
 			}
+
 			// not an EOF
 			ssn.logger.Warn().Msgf("Connection error: %v", err)
 			if netErr, ok := err.(net.Error); ok {
--- a/pkg/server/smtp/handler.go
+++ b/pkg/server/smtp/handler.go
@@ -41,7 +41,7 @@ const (
 // accepting '>' as quoted pair and in double quoted strings (?i) makes the regex case insensitive,
 // (?:) is non-grouping sub-match
 var fromRegex = regexp.MustCompile(
-	"(?i)^FROM:\\s*<((?:\\\\>|[^>])+|\"[^\"]+\"@[^>]+)>( [\\w= ]+)?$")
+	"(?i)^FROM:\\s*<((?:(?:\\\\>|[^>])+|\"[^\"]+\"@[^>])+)?>( [\\w= ]+)?$")

 func (s State) String() string {
 	switch s {
@@ -314,11 +314,15 @@ func (s *Session) readyHandler(cmd string, arg string) {
 			return
 		}
 		from := m[1]
-		if _, _, err := policy.ParseEmailAddress(from); err != nil {
+		if _, _, err := policy.ParseEmailAddress(from); from != "" && err != nil {
 			s.send("501 Bad sender address syntax")
 			s.logger.Warn().Msgf("Bad address as MAIL arg: %q, %s", from, err)
 			return
 		}
+		if from == "" {
+			from = "unspecified"
+		}
+
 		// This is where the client may put BODY=8BITMIME, but we already
 		// read the DATA as bytes, so it does not effect our processing.
 		if m[2] != "" {
@@ -433,6 +437,7 @@ func (s *Session) dataHandler() {
 			prefix := fmt.Sprintf("Received: from %s ([%s]) by %s\r\n  for <%s>; %s\r\n",
 				s.remoteDomain, s.remoteHost, s.config.Domain, recip.Address.Address,
 				tstamp)
+
 			// Deliver message.
 			_, err := s.manager.Deliver(
 				recip, s.from, s.recipients, prefix, mailData.Bytes())
@@ -527,12 +532,14 @@ func (s *Session) parseCmd(line string) (cmd string, arg string, ok bool) {
 		s.logger.Warn().Msgf("Mangled command: %q", line)
 		return "", "", false
 	}
+
 	// If we made it here, command is long enough to have args
 	if line[4] != ' ' {
 		// There wasn't a space after the command?
 		s.logger.Warn().Msgf("Mangled command: %q", line)
 		return "", "", false
 	}
+
 	// I'm not sure if we should trim the args or not, but we will for now
 	return strings.ToUpper(line[0:4]), strings.Trim(line[5:], " "), true
 }
--- a/pkg/server/smtp/handler_test.go
+++ b/pkg/server/smtp/handler_test.go
@@ -79,6 +79,35 @@ func TestGreetState(t *testing.T) {
 	}
 }

+// Test commands in READY state
+func TestEmptyEnvelope(t *testing.T) {
+	ds := test.NewStore()
+	server, logbuf, teardown := setupSMTPServer(ds)
+	defer teardown()
+
+	// Test out some empty envelope without blanks
+	script := []scriptStep{
+		{"HELO localhost", 250},
+		{"MAIL FROM:<>", 250},
+	}
+	if err := playSession(t, server, script); err != nil {
+		// Dump buffered log data if there was a failure
+		_, _ = io.Copy(os.Stderr, logbuf)
+		t.Error(err)
+	}
+
+	// Test out some empty envelope with blanks
+	script = []scriptStep{
+		{"HELO localhost", 250},
+		{"MAIL FROM: <>", 250},
+	}
+	if err := playSession(t, server, script); err != nil {
+		// Dump buffered log data if there was a failure
+		_, _ = io.Copy(os.Stderr, logbuf)
+		t.Error(err)
+	}
+}
+
 // Test commands in READY state
 func TestReadyState(t *testing.T) {
 	ds := test.NewStore()
--- a/pkg/server/web/app_json.go
+++ b/pkg/server/web/app_json.go
@@ -1,5 +1,6 @@
 package web

 type jsonAppConfig struct {
-	MonitorVisible bool `json:"monitor-visible"`
+	BasePath       string `json:"base-path"`
+	MonitorVisible bool   `json:"monitor-visible"`
 }
--- a/pkg/server/web/handlers.go
+++ b/pkg/server/web/handlers.go
@@ -1,9 +1,11 @@
 package web

 import (
+	"html/template"
 	"net/http"
 	"os"

+	"github.com/inbucket/inbucket/pkg/config"
 	"github.com/rs/zerolog/log"
 )

@@ -82,3 +84,21 @@ func requestLoggingWrapper(next http.Handler) http.Handler {
 		next.ServeHTTP(w, req)
 	})
 }
+
+// spaTemplateHandler creates a handler to serve the index.html template for our SPA.
+func spaTemplateHandler(tmpl *template.Template, basePath string,
+	webConfig config.Web) http.Handler {
+	tmplData := struct {
+		BasePath string
+	}{
+		BasePath: basePath,
+	}
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		err := tmpl.Execute(w, tmplData)
+		if err != nil {
+			log.Error().Str("module", "web").Str("remote", req.RemoteAddr).Str("proto", req.Proto).
+				Str("method", req.Method).Str("path", req.RequestURI).Err(err).
+				Msg("Error rendering SPA index template")
+		}
+	})
+}
--- a/pkg/server/web/server.go
+++ b/pkg/server/web/server.go
@@ -5,10 +5,12 @@ import (
 	"context"
 	"encoding/json"
 	"expvar"
+	"html/template"
 	"net"
 	"net/http"
 	"net/http/pprof"
 	"net/url"
+	"os"
 	"path/filepath"
 	"time"

@@ -16,6 +18,7 @@ import (
 	"github.com/inbucket/inbucket/pkg/config"
 	"github.com/inbucket/inbucket/pkg/message"
 	"github.com/inbucket/inbucket/pkg/msghub"
+	"github.com/inbucket/inbucket/pkg/stringutil"
 	"github.com/rs/zerolog/log"
 )

@@ -56,33 +59,59 @@ func Initialize(
 	msgHub = mh
 	manager = mm

+	// Redirect requests to / if there is a base path configured.
+	prefix := stringutil.MakePathPrefixer(conf.Web.BasePath)
+	redirectBase := prefix("/")
+	if redirectBase != "/" {
+		log.Info().Str("module", "web").Str("phase", "startup").Str("path", redirectBase).
+			Msg("Base path configured")
+		Router.Path("/").Handler(http.RedirectHandler(redirectBase, http.StatusFound))
+	}
+
 	// Dynamic paths.
 	log.Info().Str("module", "web").Str("phase", "startup").Str("path", conf.Web.UIDir).
 		Msg("Web UI content mapped")
-	Router.Handle("/debug/vars", expvar.Handler())
+	Router.Handle(prefix("/debug/vars"), expvar.Handler())
 	if conf.Web.PProf {
-		Router.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
-		Router.HandleFunc("/debug/pprof/profile", pprof.Profile)
-		Router.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
-		Router.HandleFunc("/debug/pprof/trace", pprof.Trace)
-		Router.PathPrefix("/debug/pprof/").HandlerFunc(pprof.Index)
+		Router.HandleFunc(prefix("/debug/pprof/cmdline"), pprof.Cmdline)
+		Router.HandleFunc(prefix("/debug/pprof/profile"), pprof.Profile)
+		Router.HandleFunc(prefix("/debug/pprof/symbol"), pprof.Symbol)
+		Router.HandleFunc(prefix("/debug/pprof/trace"), pprof.Trace)
+		Router.PathPrefix(prefix("/debug/pprof/")).HandlerFunc(pprof.Index)
 		log.Warn().Str("module", "web").Str("phase", "startup").
-			Msg("Go pprof tools installed to /debug/pprof")
+			Msg("Go pprof tools installed to " + prefix("/debug/pprof"))
 	}

 	// Static paths.
-	Router.PathPrefix("/static").Handler(
-		http.StripPrefix("/", http.FileServer(http.Dir(conf.Web.UIDir))))
-	Router.Path("/favicon.png").Handler(
+	Router.PathPrefix(prefix("/static")).Handler(
+		http.StripPrefix(prefix("/"), http.FileServer(http.Dir(conf.Web.UIDir))))
+	Router.Path(prefix("/favicon.png")).Handler(
 		fileHandler(filepath.Join(conf.Web.UIDir, "favicon.png")))

+	// Parse index.html template, allowing for configuration to be passed to the SPA.
+	indexPath := filepath.Join(conf.Web.UIDir, "index.html")
+	indexTmpl, err := template.ParseFiles(indexPath)
+	if err != nil {
+		msg := "Failed to parse HTML template"
+		cwd, _ := os.Getwd()
+		log.Error().
+			Str("module", "web").
+			Str("phase", "startup").
+			Str("path", indexPath).
+			Str("cwd", cwd).
+			Err(err).
+			Msg(msg)
+		// Create a dummy template to allow tests to pass.
+		indexTmpl, _ = template.New("index.html").Parse(msg)
+	}
+
 	// SPA managed paths.
 	spaHandler := cookieHandler(appConfigCookie(conf.Web),
-		fileHandler(filepath.Join(conf.Web.UIDir, "index.html")))
-	Router.Path("/").Handler(spaHandler)
-	Router.Path("/monitor").Handler(spaHandler)
-	Router.Path("/status").Handler(spaHandler)
-	Router.PathPrefix("/m/").Handler(spaHandler)
+		spaTemplateHandler(indexTmpl, prefix("/"), conf.Web))
+	Router.Path(prefix("/")).Handler(spaHandler)
+	Router.Path(prefix("/monitor")).Handler(spaHandler)
+	Router.Path(prefix("/status")).Handler(spaHandler)
+	Router.PathPrefix(prefix("/m/")).Handler(spaHandler)

 	// Error handlers.
 	Router.NotFoundHandler = noMatchHandler(
@@ -131,6 +160,7 @@ func Start(ctx context.Context) {

 func appConfigCookie(webConfig config.Web) *http.Cookie {
 	o := &jsonAppConfig{
+		BasePath:       webConfig.BasePath,
 		MonitorVisible: webConfig.MonitorVisible,
 	}
 	b, err := json.Marshal(o)
--- a/pkg/stringutil/utils.go
+++ b/pkg/stringutil/utils.go
@@ -61,3 +61,16 @@ func SliceToLower(slice []string) {
 		slice[i] = strings.ToLower(s)
 	}
 }
+
+// MakePathPrefixer returns a function that will add the specified prefix (base) to URI strings.
+// The returned prefixer expects all provided paths to start with /.
+func MakePathPrefixer(prefix string) func(string) string {
+	prefix = strings.Trim(prefix, "/")
+	if prefix != "" {
+		prefix = "/" + prefix
+	}
+
+	return func(path string) string {
+		return prefix + path
+	}
+}
--- a/pkg/stringutil/utils_test.go
+++ b/pkg/stringutil/utils_test.go
@@ -1,6 +1,7 @@
 package stringutil_test

 import (
+	"fmt"
 	"net/mail"
 	"testing"

@@ -35,3 +36,43 @@ func TestStringAddressList(t *testing.T) {
 		}
 	}
 }
+
+func TestMakePathPrefixer(t *testing.T) {
+	testCases := []struct {
+		prefix, path, want string
+	}{
+		{prefix: "", path: "", want: ""},
+		{prefix: "", path: "relative", want: "relative"},
+		{prefix: "", path: "/qualified", want: "/qualified"},
+		{prefix: "", path: "/many/path/segments", want: "/many/path/segments"},
+		{prefix: "pfx", path: "", want: "/pfx"},
+		{prefix: "pfx", path: "/", want: "/pfx/"},
+		{prefix: "pfx", path: "relative", want: "/pfxrelative"},
+		{prefix: "pfx", path: "/qualified", want: "/pfx/qualified"},
+		{prefix: "pfx", path: "/many/path/segments", want: "/pfx/many/path/segments"},
+		{prefix: "/pfx/", path: "", want: "/pfx"},
+		{prefix: "/pfx/", path: "/", want: "/pfx/"},
+		{prefix: "/pfx/", path: "relative", want: "/pfxrelative"},
+		{prefix: "/pfx/", path: "/qualified", want: "/pfx/qualified"},
+		{prefix: "/pfx/", path: "/many/path/segments", want: "/pfx/many/path/segments"},
+		{prefix: "a/b/c", path: "", want: "/a/b/c"},
+		{prefix: "a/b/c", path: "/", want: "/a/b/c/"},
+		{prefix: "a/b/c", path: "relative", want: "/a/b/crelative"},
+		{prefix: "a/b/c", path: "/qualified", want: "/a/b/c/qualified"},
+		{prefix: "a/b/c", path: "/many/path/segments", want: "/a/b/c/many/path/segments"},
+		{prefix: "/a/b/c/", path: "", want: "/a/b/c"},
+		{prefix: "/a/b/c/", path: "/", want: "/a/b/c/"},
+		{prefix: "/a/b/c/", path: "relative", want: "/a/b/crelative"},
+		{prefix: "/a/b/c/", path: "/qualified", want: "/a/b/c/qualified"},
+		{prefix: "/a/b/c/", path: "/many/path/segments", want: "/a/b/c/many/path/segments"},
+	}
+	for _, tc := range testCases {
+		t.Run(fmt.Sprintf("prefix %s for path %s", tc.prefix, tc.path), func(t *testing.T) {
+			prefixer := stringutil.MakePathPrefixer(tc.prefix)
+			got := prefixer(tc.path)
+			if got != tc.want {
+				t.Errorf("Got: %q, want: %q", got, tc.want)
+			}
+		})
+	}
+}
--- a/shell.nix
+++ b/shell.nix
@@ -5,7 +5,10 @@ stdenv.mkDerivation rec {
  buildInputs = [
    dpkg
    elmPackages.elm
+    elmPackages.elm-analyse
    elmPackages.elm-format
+    elmPackages.elm-language-server
+    elmPackages.elm-test
    go
    golint
    nodejs-10_x
--- a/ui/elm.json
+++ b/ui/elm.json
@@ -3,25 +3,25 @@
    "source-directories": [
        "src"
    ],
-    "elm-version": "0.19.0",
+    "elm-version": "0.19.1",
    "dependencies": {
        "direct": {
            "NoRedInk/elm-json-decode-pipeline": "1.0.0",
-            "basti1302/elm-human-readable-filesize": "1.1.1",
-            "elm/browser": "1.0.1",
-            "elm/core": "1.0.2",
+            "basti1302/elm-human-readable-filesize": "1.2.0",
+            "elm/browser": "1.0.2",
+            "elm/core": "1.0.5",
            "elm/html": "1.0.0",
            "elm/http": "2.0.0",
-            "elm/json": "1.1.2",
+            "elm/json": "1.1.3",
            "elm/svg": "1.0.1",
            "elm/time": "1.0.0",
            "elm/url": "1.0.0",
            "jweir/sparkline": "4.0.0",
-            "ryannhg/date-format": "2.1.0"
+            "ryannhg/date-format": "2.3.0"
        },
        "indirect": {
-            "elm/bytes": "1.0.3",
-            "elm/file": "1.0.1",
+            "elm/bytes": "1.0.8",
+            "elm/file": "1.0.5",
            "elm/regex": "1.0.0",
            "elm/virtual-dom": "1.0.2",
            "myrho/elm-round": "1.0.4"
@@ -31,4 +31,4 @@
        "direct": {},
        "indirect": {}
    }
-}
+}
--- a/ui/package-lock.json
+++ b/ui/package-lock.json
--- a/ui/package.json
+++ b/ui/package.json
@@ -11,21 +11,20 @@
  },
  "dependencies": {},
  "devDependencies": {
-    "@babel/core": "^7.5.5",
-    "@babel/preset-env": "^7.5.5",
-    "@fortawesome/fontawesome-free": "^5.10.1",
-    "@webcomponents/webcomponentsjs": "^2.2.10",
-    "babel-loader": "^8.0.6",
-    "css-loader": "^1.0.1",
-    "elm": "^0.19.0-no-deps",
-    "elm-hot-webpack-loader": "^1.1.1",
-    "elm-webpack-loader": "^6.0.0",
-    "file-loader": "^3.0.1",
-    "html-webpack-plugin": "^3.2.0",
-    "node-elm-compiler": "^5.0.4",
-    "style-loader": "^0.23.1",
-    "webpack": "^4.39.1",
-    "webpack-cli": "^3.3.6",
-    "webpack-dev-server": "^3.8.0"
+    "@babel/core": "^7.11.4",
+    "@babel/preset-env": "^7.11.0",
+    "@fortawesome/fontawesome-free": "^5.14.0",
+    "@webcomponents/webcomponentsjs": "^2.4.4",
+    "babel-loader": "^8.1.0",
+    "css-loader": "^4.2.2",
+    "elm-hot-webpack-loader": "^1.1.7",
+    "elm-webpack-loader": "^7.0.1",
+    "file-loader": "^6.0.0",
+    "html-webpack-plugin": "^4.4.1",
+    "node-elm-compiler": "^5.0.5",
+    "style-loader": "^1.2.1",
+    "webpack": "^4.44.1",
+    "webpack-cli": "^3.3.12",
+    "webpack-dev-server": "^3.11.0"
  }
 }
--- a/ui/public/index-dev.html
+++ b/ui/public/index-dev.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <!-- This index file will be served by the webpack development server. -->
+  <base href="/">
+  <meta charset="utf-8">
+  <meta http-equiv="x-ua-compatible" content="ie=edge">
+  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+  <meta name="theme-color" content="#000000">
+  <meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
+  <meta http-equiv="Pragma" content="no-cache" />
+  <meta http-equiv="Expires" content="0" />
+  <title>Inbucket</title>
+</head>
+<body>
+  <noscript>
+    You need to enable JavaScript to run this app.
+  </noscript>
+  <div id="root"></div>
+</body>
+</html>
--- a/ui/public/index.html
+++ b/ui/public/index.html
@@ -1,6 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
+  <base href="{{ .BasePath }}">
  <meta charset="utf-8">
  <meta http-equiv="x-ua-compatible" content="ie=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
--- a/ui/src/Api.elm
+++ b/ui/src/Api.elm
@@ -6,6 +6,7 @@ module Api exposing
    , getServerConfig
    , getServerMetrics
    , markMessageSeen
+    , monitorUri
    , purgeMailbox
    , serveUrl
    )
@@ -14,10 +15,12 @@ import Data.Message as Message exposing (Message)
 import Data.MessageHeader as MessageHeader exposing (MessageHeader)
 import Data.Metrics as Metrics exposing (Metrics)
 import Data.ServerConfig as ServerConfig exposing (ServerConfig)
+import Data.Session exposing (Session)
 import Http
 import HttpUtil
 import Json.Decode as Decode
 import Json.Encode as Encode
+import String
 import Url.Builder


@@ -29,31 +32,17 @@ type alias HttpResult msg =
    Result HttpUtil.Error () -> msg


-{-| Builds a public REST API URL (see wiki).
-}
-apiV1Url : List String -> String
-apiV1Url elements =
-    Url.Builder.absolute ([ "api", "v1" ] ++ elements) []
+deleteMessage : Session -> HttpResult msg -> String -> String -> Cmd msg
+deleteMessage session msg mailboxName id =
+    HttpUtil.delete msg (apiV1Url session [ "mailbox", mailboxName, id ])


-{-| Builds an internal `serve` REST API URL; only used by this UI.
-}
-serveUrl : List String -> String
-serveUrl elements =
-    Url.Builder.absolute ([ "serve" ] ++ elements) []
-
-
-deleteMessage : HttpResult msg -> String -> String -> Cmd msg
-deleteMessage msg mailboxName id =
-    HttpUtil.delete msg (apiV1Url [ "mailbox", mailboxName, id ])
-
-
-getHeaderList : DataResult msg (List MessageHeader) -> String -> Cmd msg
-getHeaderList msg mailboxName =
+getHeaderList : Session -> DataResult msg (List MessageHeader) -> String -> Cmd msg
+getHeaderList session msg mailboxName =
    let
        context =
            { method = "GET"
-            , url = apiV1Url [ "mailbox", mailboxName ]
+            , url = apiV1Url session [ "mailbox", mailboxName ]
            }
    in
    Http.get
@@ -62,12 +51,12 @@ getHeaderList msg mailboxName =
        }


-getGreeting : DataResult msg String -> Cmd msg
-getGreeting msg =
+getGreeting : Session -> DataResult msg String -> Cmd msg
+getGreeting session msg =
    let
        context =
            { method = "GET"
-            , url = serveUrl [ "greeting" ]
+            , url = serveUrl session [ "greeting" ]
            }
    in
    Http.get
@@ -76,12 +65,12 @@ getGreeting msg =
        }


-getMessage : DataResult msg Message -> String -> String -> Cmd msg
-getMessage msg mailboxName id =
+getMessage : Session -> DataResult msg Message -> String -> String -> Cmd msg
+getMessage session msg mailboxName id =
    let
        context =
            { method = "GET"
-            , url = serveUrl [ "mailbox", mailboxName, id ]
+            , url = serveUrl session [ "mailbox", mailboxName, id ]
            }
    in
    Http.get
@@ -90,12 +79,12 @@ getMessage msg mailboxName id =
        }


-getServerConfig : DataResult msg ServerConfig -> Cmd msg
-getServerConfig msg =
+getServerConfig : Session -> DataResult msg ServerConfig -> Cmd msg
+getServerConfig session msg =
    let
        context =
            { method = "GET"
-            , url = serveUrl [ "status" ]
+            , url = serveUrl session [ "status" ]
            }
    in
    Http.get
@@ -104,12 +93,19 @@ getServerConfig msg =
        }


-getServerMetrics : DataResult msg Metrics -> Cmd msg
-getServerMetrics msg =
+getServerMetrics : Session -> DataResult msg Metrics -> Cmd msg
+getServerMetrics session msg =
    let
        context =
            { method = "GET"
-            , url = Url.Builder.absolute [ "debug", "vars" ] []
+            , url =
+                Url.Builder.absolute
+                    (splitBasePath session.config.basePath
+                        ++ [ "debug"
+                           , "vars"
+                           ]
+                    )
+                    []
            }
    in
    Http.get
@@ -118,15 +114,73 @@ getServerMetrics msg =
        }


-markMessageSeen : HttpResult msg -> String -> String -> Cmd msg
-markMessageSeen msg mailboxName id =
+markMessageSeen : Session -> HttpResult msg -> String -> String -> Cmd msg
+markMessageSeen session msg mailboxName id =
    -- The URL tells the API which message ID to update, so we only need to indicate the
    -- desired change in the body.
    Encode.object [ ( "seen", Encode.bool True ) ]
        |> Http.jsonBody
-        |> HttpUtil.patch msg (apiV1Url [ "mailbox", mailboxName, id ])
+        |> HttpUtil.patch msg (apiV1Url session [ "mailbox", mailboxName, id ])


-purgeMailbox : HttpResult msg -> String -> Cmd msg
-purgeMailbox msg mailboxName =
-    HttpUtil.delete msg (apiV1Url [ "mailbox", mailboxName ])
+monitorUri : Session -> String
+monitorUri session =
+    apiV1Url session [ "monitor", "messages" ]
+
+
+purgeMailbox : Session -> HttpResult msg -> String -> Cmd msg
+purgeMailbox session msg mailboxName =
+    HttpUtil.delete msg (apiV1Url session [ "mailbox", mailboxName ])
+
+
+{-| Builds a public REST API URL (see wiki).
+-}
+apiV1Url : Session -> List String -> String
+apiV1Url session elements =
+    Url.Builder.absolute
+        (List.concat
+            [ splitBasePath session.config.basePath
+            , [ "api", "v1" ]
+            , elements
+            ]
+        )
+        []
+
+
+{-| Builds an internal `serve` REST API URL; only used by this UI.
+-}
+serveUrl : Session -> List String -> String
+serveUrl session elements =
+    Url.Builder.absolute
+        (List.concat
+            [ splitBasePath session.config.basePath
+            , [ "serve" ]
+            , elements
+            ]
+        )
+        []
+
+
+{-| Converts base path into a list of path elements.
+-}
+splitBasePath : String -> List String
+splitBasePath path =
+    if path == "" then
+        []
+
+    else
+        let
+            stripSlashes str =
+                if String.startsWith "/" str then
+                    stripSlashes (String.dropLeft 1 str)
+
+                else if String.endsWith "/" str then
+                    stripSlashes (String.dropRight 1 str)
+
+                else
+                    str
+
+            newPath =
+                stripSlashes path
+        in
+        String.split "/" newPath
--- a/ui/src/Data/AppConfig.elm
+++ b/ui/src/Data/AppConfig.elm
@@ -5,16 +5,18 @@ import Json.Decode.Pipeline as P


 type alias AppConfig =
-    { monitorVisible : Bool
+    { basePath : String
+    , monitorVisible : Bool
    }


 decoder : D.Decoder AppConfig
 decoder =
    D.succeed AppConfig
+        |> P.optional "base-path" D.string ""
        |> P.required "monitor-visible" D.bool


 default : AppConfig
 default =
-    AppConfig True
+    AppConfig "" True
--- a/ui/src/Data/Date.elm
+++ b/ui/src/Data/Date.elm
@@ -1,6 +1,6 @@
 module Data.Date exposing (date)

-import Json.Decode exposing (..)
+import Json.Decode exposing (Decoder, int, map)
 import Time exposing (Posix)


--- a/ui/src/Data/Message.elm
+++ b/ui/src/Data/Message.elm
@@ -1,8 +1,8 @@
 module Data.Message exposing (Attachment, Message, attachmentDecoder, decoder)

 import Data.Date exposing (date)
-import Json.Decode exposing (..)
-import Json.Decode.Pipeline exposing (..)
+import Json.Decode exposing (Decoder, bool, int, list, string, succeed)
+import Json.Decode.Pipeline exposing (optional, required)
 import Time exposing (Posix)


--- a/ui/src/Data/MessageHeader.elm
+++ b/ui/src/Data/MessageHeader.elm
@@ -1,8 +1,8 @@
 module Data.MessageHeader exposing (MessageHeader, decoder)

 import Data.Date exposing (date)
-import Json.Decode exposing (..)
-import Json.Decode.Pipeline exposing (..)
+import Json.Decode exposing (Decoder, bool, int, list, string, succeed)
+import Json.Decode.Pipeline exposing (optional, required)
 import Time exposing (Posix)


--- a/ui/src/Data/Metrics.elm
+++ b/ui/src/Data/Metrics.elm
@@ -1,8 +1,8 @@
 module Data.Metrics exposing (Metrics, decodeIntList, decoder)

 import Data.Date exposing (date)
-import Json.Decode as Decode exposing (..)
-import Json.Decode.Pipeline exposing (..)
+import Json.Decode exposing (Decoder, int, map, string, succeed)
+import Json.Decode.Pipeline exposing (requiredAt)
 import Time exposing (Posix)


--- a/ui/src/Data/Session.elm
+++ b/ui/src/Data/Session.elm
@@ -15,11 +15,10 @@ module Data.Session exposing

 import Browser.Navigation as Nav
 import Data.AppConfig as AppConfig exposing (AppConfig)
-import Html exposing (Html)
 import Json.Decode as D
-import Json.Decode.Pipeline exposing (..)
+import Json.Decode.Pipeline exposing (optional)
 import Json.Encode as E
-import Ports
+import Route exposing (Router)
 import Time
 import Url exposing (Url)

@@ -29,6 +28,7 @@ type alias Session =
    , host : String
    , flash : Maybe Flash
    , routing : Bool
+    , router : Router
    , zone : Time.Zone
    , config : AppConfig
    , persistent : Persistent
@@ -52,6 +52,7 @@ init key location config persistent =
    , host = location.host
    , flash = Nothing
    , routing = True
+    , router = Route.newRouter config.basePath
    , zone = Time.utc
    , config = config
    , persistent = persistent
@@ -64,6 +65,7 @@ initError key location error =
    , host = location.host
    , flash = Just (Flash "Initialization failed" [ ( "Error", error ) ])
    , routing = True
+    , router = Route.newRouter ""
    , zone = Time.utc
    , config = AppConfig.default
    , persistent = Persistent []
--- a/ui/src/HttpUtil.elm
+++ b/ui/src/HttpUtil.elm
@@ -1,7 +1,6 @@
 module HttpUtil exposing (Error, RequestContext, delete, errorFlash, expectJson, expectString, patch)

 import Data.Session as Session
-import Html exposing (Html, div, text)
 import Http
 import Json.Decode as Decode

--- a/ui/src/Layout.elm
+++ b/ui/src/Layout.elm
@@ -1,23 +1,46 @@
 module Layout exposing (Model, Msg, Page(..), frame, init, reset, update)

+import Browser.Navigation as Nav
 import Data.Session as Session exposing (Session)
-import Html exposing (..)
+import Html
+    exposing
+        ( Attribute
+        , Html
+        , a
+        , button
+        , div
+        , footer
+        , form
+        , h2
+        , header
+        , i
+        , input
+        , li
+        , nav
+        , pre
+        , span
+        , td
+        , text
+        , th
+        , tr
+        , ul
+        )
 import Html.Attributes
    exposing
        ( attribute
        , class
        , classList
        , href
-        , id
        , placeholder
        , rel
-        , selected
        , target
        , type_
        , value
        )
 import Html.Events as Events
+import Modal
 import Route exposing (Route)
+import Timer exposing (Timer)


 {-| Used to highlight current page in navbar.
@@ -31,8 +54,9 @@ type Page

 type alias Model msg =
    { mapMsg : Msg -> msg
-    , menuVisible : Bool
-    , recentVisible : Bool
+    , mainMenuVisible : Bool
+    , recentMenuVisible : Bool
+    , recentMenuTimer : Timer
    , mailboxName : String
    }

@@ -40,8 +64,9 @@ type alias Model msg =
 init : (Msg -> msg) -> Model msg
 init mapMsg =
    { mapMsg = mapMsg
-    , menuVisible = False
-    , recentVisible = False
+    , mainMenuVisible = False
+    , recentMenuVisible = False
+    , recentMenuTimer = Timer.empty
    , mailboxName = ""
    }

@@ -51,18 +76,24 @@ init mapMsg =
 reset : Model msg -> Model msg
 reset model =
    { model
-        | menuVisible = False
-        , recentVisible = False
+        | mainMenuVisible = False
+        , recentMenuVisible = False
+        , recentMenuTimer = Timer.cancel model.recentMenuTimer
        , mailboxName = ""
    }


 type Msg
    = ClearFlash
+    | MainMenuToggled
+    | ModalFocused Modal.Msg
+    | ModalUnfocused
    | OnMailboxNameInput String
    | OpenMailbox
-    | ShowRecent Bool
-    | ToggleMenu
+    | RecentMenuMouseOver
+    | RecentMenuMouseOut
+    | RecentMenuTimeout Timer
+    | RecentMenuToggled


 update : Msg -> Model msg -> Session -> ( Model msg, Session, Cmd msg )
@@ -74,6 +105,21 @@ update msg model session =
            , Cmd.none
            )

+        MainMenuToggled ->
+            ( { model | mainMenuVisible = not model.mainMenuVisible }
+            , session
+            , Cmd.none
+            )
+
+        ModalFocused message ->
+            ( model
+            , Modal.updateSession message session
+            , Cmd.none
+            )
+
+        ModalUnfocused ->
+            ( model, session, Modal.resetFocusCmd (ModalFocused >> model.mapMsg) )
+
        OnMailboxNameInput name ->
            ( { model | mailboxName = name }
            , session
@@ -87,17 +133,48 @@ update msg model session =
            else
                ( model
                , session
-                , Route.pushUrl session.key (Route.Mailbox model.mailboxName)
+                , Route.Mailbox model.mailboxName
+                    |> session.router.toPath
+                    |> Nav.pushUrl session.key
                )

-        ShowRecent visible ->
-            ( { model | recentVisible = visible }
+        RecentMenuMouseOver ->
+            ( { model
+                | recentMenuVisible = True
+                , recentMenuTimer = Timer.cancel model.recentMenuTimer
+              }
            , session
            , Cmd.none
            )

-        ToggleMenu ->
-            ( { model | menuVisible = not model.menuVisible }
+        RecentMenuMouseOut ->
+            let
+                newTimer =
+                    Timer.replace model.recentMenuTimer
+            in
+            ( { model
+                | recentMenuTimer = newTimer
+              }
+            , session
+            , Timer.schedule (RecentMenuTimeout >> model.mapMsg) newTimer 400
+            )
+
+        RecentMenuTimeout timer ->
+            if timer == model.recentMenuTimer then
+                ( { model
+                    | recentMenuVisible = False
+                    , recentMenuTimer = Timer.cancel timer
+                  }
+                , session
+                , Cmd.none
+                )
+
+            else
+                -- Timer was no longer valid.
+                ( model, session, Cmd.none )
+
+        RecentMenuToggled ->
+            ( { model | recentMenuVisible = not model.recentMenuVisible }
            , session
            , Cmd.none
            )
@@ -118,17 +195,17 @@ frame { model, session, activePage, activeMailbox, modal, content } =
    div [ class "app" ]
        [ header []
            [ nav [ class "navbar" ]
-                [ button [ class "navbar-toggle", Events.onClick (ToggleMenu |> model.mapMsg) ]
+                [ button [ class "navbar-toggle", Events.onClick (MainMenuToggled |> model.mapMsg) ]
                    [ i [ class "fas fa-bars" ] [] ]
                , span [ class "navbar-brand" ]
-                    [ a [ Route.href Route.Home ] [ text "@ inbucket" ] ]
-                , ul [ class "main-nav", classList [ ( "active", model.menuVisible ) ] ]
+                    [ a [ href <| session.router.toPath Route.Home ] [ text "@ inbucket" ] ]
+                , ul [ class "main-nav", classList [ ( "active", model.mainMenuVisible ) ] ]
                    [ if session.config.monitorVisible then
-                        navbarLink Monitor Route.Monitor [ text "Monitor" ] activePage
+                        navbarLink Monitor (session.router.toPath Route.Monitor) [ text "Monitor" ] activePage

                      else
                        text ""
-                    , navbarLink Status Route.Status [ text "Status" ] activePage
+                    , navbarLink Status (session.router.toPath Route.Status) [ text "Status" ] activePage
                    , navbarRecent activePage activeMailbox model session
                    , li [ class "navbar-mailbox" ]
                        [ form [ Events.onSubmit (OpenMailbox |> model.mapMsg) ]
@@ -145,8 +222,8 @@ frame { model, session, activePage, activeMailbox, modal, content } =
                ]
            ]
        , div [ class "navbar-bg" ] [ text "" ]
-        , frameModal modal
-        , div [ class "page" ] ([ errorFlash model session.flash ] ++ content)
+        , Modal.view (ModalUnfocused |> model.mapMsg) modal
+        , div [ class "page" ] (errorFlash model session.flash :: content)
        , footer []
            [ div [ class "footer" ]
                [ externalLink "https://www.inbucket.org" "Inbucket"
@@ -158,18 +235,6 @@ frame { model, session, activePage, activeMailbox, modal, content } =
        ]


-frameModal : Maybe (Html msg) -> Html msg
-frameModal maybeModal =
-    case maybeModal of
-        Just modal ->
-            div [ class "modal-mask" ]
-                [ div [ class "modal well" ] [ modal ]
-                ]
-
-        Nothing ->
-            text ""
-
-
 errorFlash : Model msg -> Maybe Session.Flash -> Html msg
 errorFlash model maybeFlash =
    let
@@ -198,10 +263,10 @@ externalLink url title =
    a [ href url, target "_blank", rel "noopener" ] [ text title ]


-navbarLink : Page -> Route -> List (Html a) -> Page -> Html a
-navbarLink page route linkContent activePage =
+navbarLink : Page -> String -> List (Html a) -> Page -> Html a
+navbarLink page url linkContent activePage =
    li [ classList [ ( "navbar-active", page == activePage ) ] ]
-        [ a [ Route.href route ] linkContent ]
+        [ a [ href url ] linkContent ]


 {-| Renders list of recent mailboxes, selecting the currently active mailbox.
@@ -229,29 +294,22 @@ navbarRecent page activeMailbox model session =
            else
                session.persistent.recentMailboxes

-        dropdownExpanded =
-            if model.recentVisible then
-                "true"
-
-            else
-                "false"
-
        recentLink mailbox =
-            a [ Route.href (Route.Mailbox mailbox) ] [ text mailbox ]
+            a [ href <| session.router.toPath <| Route.Mailbox mailbox ] [ text mailbox ]
    in
    li
        [ class "navbar-dropdown-container"
        , classList [ ( "navbar-active", active ) ]
        , attribute "aria-haspopup" "true"
-        , ariaExpanded model.recentVisible
-        , Events.onMouseOver (ShowRecent True |> model.mapMsg)
-        , Events.onMouseOut (ShowRecent False |> model.mapMsg)
+        , ariaExpanded model.recentMenuVisible
+        , Events.onMouseOver (RecentMenuMouseOver |> model.mapMsg)
+        , Events.onMouseOut (RecentMenuMouseOut |> model.mapMsg)
        ]
        [ span [ class "navbar-dropdown" ]
            [ text title
            , button
                [ class "navbar-dropdown-button"
-                , Events.onClick (ShowRecent (not model.recentVisible) |> model.mapMsg)
+                , Events.onClick (RecentMenuToggled |> model.mapMsg)
                ]
                [ i [ class "fas fa-chevron-down" ] [] ]
            ]
--- a/ui/src/Main.elm
+++ b/ui/src/Main.elm
@@ -4,7 +4,7 @@ import Browser exposing (Document, UrlRequest)
 import Browser.Navigation as Nav
 import Data.AppConfig as AppConfig exposing (AppConfig)
 import Data.Session as Session exposing (Session)
-import Html exposing (..)
+import Html exposing (Html)
 import Json.Decode as D exposing (Value)
 import Layout
 import Page.Home as Home
@@ -66,7 +66,7 @@ init configValue location key =
            }

        route =
-            Route.fromUrl location
+            session.router.fromUrl location

        ( model, cmd ) =
            changeRouteTo route initModel
@@ -167,7 +167,7 @@ updateMain msg model session =
        UrlChanged url ->
            -- Responds to new browser URL.
            if session.routing then
-                changeRouteTo (Route.fromUrl url) model
+                changeRouteTo (session.router.fromUrl url) model

            else
                -- Skip once, but re-enable routing.
--- a/ui/src/Modal.elm
+++ b/ui/src/Modal.elm
@@ -0,0 +1,58 @@
+module Modal exposing (Msg, resetFocusCmd, updateSession, view)
+
+import Browser.Dom as Dom
+import Data.Session as Session exposing (Session)
+import Html exposing (Html, div, span, text)
+import Html.Attributes exposing (class, id, tabindex)
+import Html.Events exposing (onFocus)
+import Task
+
+
+type alias Msg =
+    Result Dom.Error ()
+
+
+{-| Creates a command to focus the modal dialog.
+-}
+resetFocusCmd : (Msg -> msg) -> Cmd msg
+resetFocusCmd resultMsg =
+    Task.attempt resultMsg (Dom.focus domId)
+
+
+{-| Updates a Session with an error Flash if the resetFocusCmd failed.
+-}
+updateSession : Msg -> Session -> Session
+updateSession result session =
+    case result of
+        Ok () ->
+            session
+
+        Err (Dom.NotFound missingDomId) ->
+            let
+                flash =
+                    { title = "DOM element not found"
+                    , table = [ ( "Element ID", missingDomId ) ]
+                    }
+            in
+            Session.showFlash flash session
+
+
+view : msg -> Maybe (Html msg) -> Html msg
+view unfocusedMsg maybeModal =
+    case maybeModal of
+        Just modal ->
+            div [ class "modal-mask" ]
+                [ span [ onFocus unfocusedMsg, tabindex 0 ] []
+                , div [ id domId, class "modal well", tabindex -1 ] [ modal ]
+                , span [ onFocus unfocusedMsg, tabindex 0 ] []
+                ]
+
+        Nothing ->
+            text ""
+
+
+{-| DOM ID of the modal dialog.
+-}
+domId : String
+domId =
+    "modal-dialog"
--- a/ui/src/Page/Home.elm
+++ b/ui/src/Page/Home.elm
@@ -2,12 +2,10 @@ module Page.Home exposing (Model, Msg, init, update, view)

 import Api
 import Data.Session as Session exposing (Session)
-import Html exposing (..)
-import Html.Attributes exposing (..)
-import Http
+import Html exposing (Html)
+import Html.Attributes exposing (class, property)
 import HttpUtil
 import Json.Encode as Encode
-import Ports



@@ -22,7 +20,7 @@ type alias Model =

 init : Session -> ( Model, Cmd Msg )
 init session =
-    ( Model session "", Api.getGreeting GreetingLoaded )
+    ( Model session "", Api.getGreeting session GreetingLoaded )



--- a/ui/src/Page/Mailbox.elm
+++ b/ui/src/Page/Mailbox.elm
@@ -1,12 +1,38 @@
 module Page.Mailbox exposing (Model, Msg, init, load, subscriptions, update, view)

 import Api
+import Browser.Navigation as Nav
 import Data.Message as Message exposing (Message)
-import Data.MessageHeader as MessageHeader exposing (MessageHeader)
+import Data.MessageHeader exposing (MessageHeader)
 import Data.Session as Session exposing (Session)
 import DateFormat as DF
 import DateFormat.Relative as Relative
-import Html exposing (..)
+import Html
+    exposing
+        ( Attribute
+        , Html
+        , a
+        , article
+        , aside
+        , button
+        , dd
+        , div
+        , dl
+        , dt
+        , h3
+        , i
+        , input
+        , li
+        , main_
+        , nav
+        , p
+        , span
+        , table
+        , td
+        , text
+        , tr
+        , ul
+        )
 import Html.Attributes
    exposing
        ( alt
@@ -15,7 +41,6 @@ import Html.Attributes
        , disabled
        , download
        , href
-        , id
        , placeholder
        , property
        , tabindex
@@ -24,14 +49,14 @@ import Html.Attributes
        , value
        )
 import Html.Events as Events
-import Http exposing (Error)
 import HttpUtil
 import Json.Decode as D
 import Json.Encode as E
-import Ports
+import Modal
 import Route
 import Task
 import Time exposing (Posix)
+import Timer exposing (Timer)



@@ -51,8 +76,8 @@ type State
 type MessageState
    = NoMessage
    | LoadingMessage
-    | ShowingMessage VisibleMessage
-    | Transitioning VisibleMessage
+    | ShowingMessage Message
+    | Transitioning Message


 type alias MessageID =
@@ -66,12 +91,6 @@ type alias MessageList =
    }


-type alias VisibleMessage =
-    { message : Message
-    , markSeenAt : Maybe Int
-    }
-
-
 type alias Model =
    { session : Session
    , mailboxName : String
@@ -79,6 +98,7 @@ type alias Model =
    , bodyMode : Body
    , searchInput : String
    , promptPurge : Bool
+    , markSeenTimer : Timer
    , now : Posix
    }

@@ -91,17 +111,18 @@ init session mailboxName selection =
      , bodyMode = SafeHtmlBody
      , searchInput = ""
      , promptPurge = False
+      , markSeenTimer = Timer.empty
      , now = Time.millisToPosix 0
      }
-    , load mailboxName
+    , load session mailboxName
    )


-load : String -> Cmd Msg
-load mailboxName =
+load : Session -> String -> Cmd Msg
+load session mailboxName =
    Cmd.batch
        [ Task.perform Tick Time.now
-        , Api.getHeaderList ListLoaded mailboxName
+        , Api.getHeaderList session ListLoaded mailboxName
        ]


@@ -110,24 +131,8 @@ load mailboxName =


 subscriptions : Model -> Sub Msg
-subscriptions model =
-    let
-        subSeen =
-            case model.state of
-                ShowingList _ (ShowingMessage { message }) ->
-                    if message.seen then
-                        Sub.none
-
-                    else
-                        Time.every 250 MarkSeenTick
-
-                _ ->
-                    Sub.none
-    in
-    Sub.batch
-        [ Time.every (30 * 1000) Tick
-        , subSeen
-        ]
+subscriptions _ =
+    Time.every (30 * 1000) Tick



@@ -138,13 +143,11 @@ type Msg
    = ListLoaded (Result HttpUtil.Error (List MessageHeader))
    | ClickMessage MessageID
    | ListKeyPress String Int
-    | OpenMessage MessageID
    | CloseMessage
    | MessageLoaded (Result HttpUtil.Error Message)
    | MessageBody Body
-    | OpenedTime Posix
-    | MarkSeenTick Posix
-    | MarkedSeen (Result HttpUtil.Error ())
+    | MarkSeenTriggered Timer
+    | MarkSeenLoaded (Result HttpUtil.Error ())
    | DeleteMessage Message
    | DeletedMessage (Result HttpUtil.Error ())
    | PurgeMailboxPrompt
@@ -153,6 +156,7 @@ type Msg
    | PurgedMailbox (Result HttpUtil.Error ())
    | OnSearchInput String
    | Tick Posix
+    | ModalFocused Modal.Msg


 update : Msg -> Model -> ( Model, Cmd Msg )
@@ -162,14 +166,13 @@ update msg model =
            ( updateSelected { model | session = Session.disableRouting model.session } id
            , Cmd.batch
                [ -- Update browser location.
-                  Route.replaceUrl model.session.key (Route.Message model.mailboxName id)
-                , Api.getMessage MessageLoaded model.mailboxName id
+                  Route.Message model.mailboxName id
+                    |> model.session.router.toPath
+                    |> Nav.replaceUrl model.session.key
+                , Api.getMessage model.session MessageLoaded model.mailboxName id
                ]
            )

-        OpenMessage id ->
-            updateOpenMessage model id
-
        CloseMessage ->
            case model.state of
                ShowingList list _ ->
@@ -225,10 +228,10 @@ update msg model =
            , Cmd.none
            )

-        MarkedSeen (Ok _) ->
+        MarkSeenLoaded (Ok _) ->
            ( model, Cmd.none )

-        MarkedSeen (Err err) ->
+        MarkSeenLoaded (Err err) ->
            ( { model | session = Session.showFlash (HttpUtil.errorFlash err) model.session }
            , Cmd.none
            )
@@ -244,44 +247,22 @@ update msg model =
        MessageBody bodyMode ->
            ( { model | bodyMode = bodyMode }, Cmd.none )

+        ModalFocused message ->
+            ( { model | session = Modal.updateSession message model.session }
+            , Cmd.none
+            )
+
        OnSearchInput searchInput ->
            updateSearchInput model searchInput

-        OpenedTime time ->
-            case model.state of
-                ShowingList list (ShowingMessage visible) ->
-                    if visible.message.seen then
-                        ( model, Cmd.none )
-
-                    else
-                        -- Set 1500ms delay before reporting message as seen to backend.
-                        let
-                            markSeenAt =
-                                Time.posixToMillis time + 1500
-                        in
-                        ( { model
-                            | state =
-                                ShowingList list
-                                    (ShowingMessage
-                                        { visible
-                                            | markSeenAt = Just markSeenAt
-                                        }
-                                    )
-                          }
-                        , Cmd.none
-                        )
-
-                _ ->
-                    ( model, Cmd.none )
-
        PurgeMailboxPrompt ->
-            ( { model | promptPurge = True }, Cmd.none )
+            ( { model | promptPurge = True }, Modal.resetFocusCmd ModalFocused )

        PurgeMailboxCanceled ->
            ( { model | promptPurge = False }, Cmd.none )

        PurgeMailboxConfirmed ->
-            updatePurge model
+            updateTriggerPurge model

        PurgedMailbox (Ok _) ->
            ( model, Cmd.none )
@@ -291,22 +272,13 @@ update msg model =
            , Cmd.none
            )

-        MarkSeenTick now ->
-            case model.state of
-                ShowingList _ (ShowingMessage { message, markSeenAt }) ->
-                    case markSeenAt of
-                        Just deadline ->
-                            if Time.posixToMillis now >= deadline then
-                                updateMarkMessageSeen model message
+        MarkSeenTriggered timer ->
+            if timer == model.markSeenTimer then
+                -- Matching timer means we have changed messages, mark this one seen.
+                updateMarkMessageSeen model

-                            else
-                                ( model, Cmd.none )
-
-                        Nothing ->
-                            ( model, Cmd.none )
-
-                _ ->
-                    ( model, Cmd.none )
+            else
+                ( model, Cmd.none )

        Tick now ->
            ( { model | now = now }, Cmd.none )
@@ -329,28 +301,38 @@ updateMessageResult model message =
            ( model, Cmd.none )

        ShowingList list _ ->
+            let
+                newTimer =
+                    Timer.replace model.markSeenTimer
+            in
            ( { model
                | state =
                    ShowingList
                        { list | selected = Just message.id }
-                        (ShowingMessage (VisibleMessage message Nothing))
+                        (ShowingMessage message)
                , bodyMode = bodyMode
+                , markSeenTimer = newTimer
              }
-            , Task.perform OpenedTime Time.now
+              -- Set 1500ms delay before reporting message as seen to backend.
+            , Timer.schedule MarkSeenTriggered newTimer 1500
            )


-updatePurge : Model -> ( Model, Cmd Msg )
-updatePurge model =
+{-| Updates model and triggers commands to purge this mailbox.
+-}
+updateTriggerPurge : Model -> ( Model, Cmd Msg )
+updateTriggerPurge model =
    let
        cmd =
            Cmd.batch
-                [ Route.replaceUrl model.session.key (Route.Mailbox model.mailboxName)
-                , Api.purgeMailbox PurgedMailbox model.mailboxName
+                [ Route.Mailbox model.mailboxName
+                    |> model.session.router.toPath
+                    |> Nav.replaceUrl model.session.key
+                , Api.purgeMailbox model.session PurgedMailbox model.mailboxName
                ]
    in
    case model.state of
-        ShowingList list _ ->
+        ShowingList _ _ ->
            ( { model
                | promptPurge = False
                , session = Session.disableRouting model.session
@@ -428,8 +410,10 @@ updateDeleteMessage model message =
                    ShowingList (filter (\x -> x.id /= message.id) list) NoMessage
              }
            , Cmd.batch
-                [ Api.deleteMessage DeletedMessage message.mailbox message.id
-                , Route.replaceUrl model.session.key (Route.Mailbox model.mailboxName)
+                [ Api.deleteMessage model.session DeletedMessage message.mailbox message.id
+                , Route.Mailbox model.mailboxName
+                    |> model.session.router.toPath
+                    |> Nav.replaceUrl model.session.key
                ]
            )

@@ -437,32 +421,28 @@ updateDeleteMessage model message =
            ( model, Cmd.none )


-updateMarkMessageSeen : Model -> Message -> ( Model, Cmd Msg )
-updateMarkMessageSeen model message =
+{-| Updates both the active message, and the message list to mark the currently viewed message as seen.
+-}
+updateMarkMessageSeen : Model -> ( Model, Cmd Msg )
+updateMarkMessageSeen model =
    case model.state of
-        ShowingList list (ShowingMessage visible) ->
+        ShowingList messages (ShowingMessage visibleMessage) ->
            let
-                updateSeen header =
-                    if header.id == message.id then
+                updateHeader header =
+                    if header.id == visibleMessage.id then
                        { header | seen = True }

                    else
                        header

-                map f messageList =
-                    { messageList | headers = List.map f messageList.headers }
+                newMessages =
+                    { messages | headers = List.map updateHeader messages.headers }
            in
            ( { model
                | state =
-                    ShowingList (map updateSeen list)
-                        (ShowingMessage
-                            { visible
-                                | message = { message | seen = True }
-                                , markSeenAt = Nothing
-                            }
-                        )
+                    ShowingList newMessages (ShowingMessage { visibleMessage | seen = True })
              }
-            , Api.markMessageSeen MarkedSeen message.mailbox message.id
+            , Api.markMessageSeen model.session MarkSeenLoaded visibleMessage.mailbox visibleMessage.id
            )

        _ ->
@@ -476,7 +456,7 @@ updateOpenMessage model id =
            { model | session = Session.addRecent model.mailboxName model.session }
    in
    ( updateSelected newModel id
-    , Api.getMessage MessageLoaded model.mailboxName id
+    , Api.getMessage model.session MessageLoaded model.mailboxName id
    )


@@ -529,11 +509,11 @@ view model =
                                ++ " or enter a different username into the box on upper right."
                            )

-                    ShowingList _ (ShowingMessage { message }) ->
-                        viewMessage model.session.zone message model.bodyMode
+                    ShowingList _ (ShowingMessage message) ->
+                        viewMessage model.session model.session.zone message model.bodyMode

-                    ShowingList _ (Transitioning { message }) ->
-                        viewMessage model.session.zone message model.bodyMode
+                    ShowingList _ (Transitioning message) ->
+                        viewMessage model.session model.session.zone message model.bodyMode

                    _ ->
                        text ""
@@ -591,14 +571,14 @@ messageChip model selected message =
        ]


-viewMessage : Time.Zone -> Message -> Body -> Html Msg
-viewMessage zone message bodyMode =
+viewMessage : Session -> Time.Zone -> Message -> Body -> Html Msg
+viewMessage session zone message bodyMode =
    let
        htmlUrl =
-            Api.serveUrl [ "mailbox", message.mailbox, message.id, "html" ]
+            Api.serveUrl session [ "mailbox", message.mailbox, message.id, "html" ]

        sourceUrl =
-            Api.serveUrl [ "mailbox", message.mailbox, message.id, "source" ]
+            Api.serveUrl session [ "mailbox", message.mailbox, message.id, "source" ]

        htmlButton =
            if message.html == "" then
@@ -629,7 +609,7 @@ viewMessage zone message bodyMode =
            ]
        , messageErrors message
        , messageBody message bodyMode
-        , attachments message
+        , attachments session message
        ]


@@ -692,20 +672,20 @@ messageBody message bodyMode =
        ]


-attachments : Message -> Html Msg
-attachments message =
+attachments : Session -> Message -> Html Msg
+attachments session message =
    if List.isEmpty message.attachments then
        div [] []

    else
-        table [ class "attachments well" ] (List.map (attachmentRow message) message.attachments)
+        table [ class "attachments well" ] (List.map (attachmentRow session message) message.attachments)


-attachmentRow : Message -> Message.Attachment -> Html Msg
-attachmentRow message attach =
+attachmentRow : Session -> Message -> Message.Attachment -> Html Msg
+attachmentRow session message attach =
    let
        url =
-            Api.serveUrl
+            Api.serveUrl session
                [ "mailbox"
                , message.mailbox
                , message.id
--- a/ui/src/Page/Monitor.elm
+++ b/ui/src/Page/Monitor.elm
@@ -1,10 +1,29 @@
 module Page.Monitor exposing (Model, Msg, init, update, view)

+import Api
+import Browser.Navigation as Nav
 import Data.MessageHeader as MessageHeader exposing (MessageHeader)
 import Data.Session as Session exposing (Session)
 import DateFormat as DF
-import Html exposing (..)
-import Html.Attributes exposing (..)
+import Html
+    exposing
+        ( Attribute
+        , Html
+        , button
+        , div
+        , em
+        , h1
+        , node
+        , span
+        , table
+        , tbody
+        , td
+        , text
+        , th
+        , thead
+        , tr
+        )
+import Html.Attributes exposing (class, src, tabindex)
 import Html.Events as Events
 import Json.Decode as D
 import Route
@@ -84,7 +103,9 @@ update msg model =
 openMessage : MessageHeader -> Model -> ( Model, Cmd Msg )
 openMessage header model =
    ( model
-    , Route.pushUrl model.session.key (Route.Message header.mailbox header.id)
+    , Route.Message header.mailbox header.id
+        |> model.session.router.toPath
+        |> Nav.replaceUrl model.session.key
    )


@@ -115,8 +136,12 @@ view model =
                [ button [ Events.onClick Clear ] [ text "Clear" ]
                ]
            ]
+
+        -- monitor-messages maintains a websocket connection to the Inbucket daemon at the path
+        -- specified by `src`.
        , node "monitor-messages"
-            [ Events.on "connected" (D.map Connected <| D.at [ "detail" ] <| D.bool)
+            [ src (Api.monitorUri model.session)
+            , Events.on "connected" (D.map Connected <| D.at [ "detail" ] <| D.bool)
            , Events.on "message" (D.map MessageReceived D.value)
            ]
            []
--- a/ui/src/Page/Status.elm
+++ b/ui/src/Page/Status.elm
@@ -1,14 +1,21 @@
 module Page.Status exposing (Model, Msg, init, subscriptions, update, view)

 import Api
-import Data.Metrics as Metrics exposing (Metrics)
-import Data.ServerConfig as ServerConfig exposing (ServerConfig)
+import Data.Metrics exposing (Metrics)
+import Data.ServerConfig exposing (ServerConfig)
 import Data.Session as Session exposing (Session)
 import DateFormat.Relative as Relative
 import Filesize
-import Html exposing (..)
-import Html.Attributes exposing (..)
-import Http exposing (Error)
+import Html
+    exposing
+        ( Html
+        , div
+        , h1
+        , h2
+        , i
+        , text
+        )
+import Html.Attributes exposing (class)
 import HttpUtil
 import Sparkline as Spark
 import Svg.Attributes as SvgAttrib
@@ -77,7 +84,7 @@ init session =
      }
    , Cmd.batch
        [ Task.perform Tick Time.now
-        , Api.getServerConfig ServerConfigLoaded
+        , Api.getServerConfig session ServerConfigLoaded
        ]
    )

@@ -93,7 +100,7 @@ initDataSet =


 subscriptions : Model -> Sub Msg
-subscriptions model =
+subscriptions _ =
    Time.every (10 * 1000) Tick


@@ -127,7 +134,7 @@ update msg model =
            )

        Tick time ->
-            ( { model | now = time }, Api.getServerMetrics MetricsReceived )
+            ( { model | now = time }, Api.getServerMetrics model.session MetricsReceived )


 {-| Update all metrics in Model; increment xCounter.
@@ -271,18 +278,19 @@ configPanel maybeConfig =
                , textEntry "SMTP Listener" config.smtpConfig.addr
                , textEntry "POP3 Listener" config.pop3Listener
                , textEntry "HTTP Listener" config.webListener
-                , textEntry "Accept Policy" (acceptPolicy config.smtpConfig)
-                , textEntry "Store Policy" (storePolicy config.smtpConfig)
+                , textEntry "Accept Policy" (acceptPolicy config)
+                , textEntry "Store Policy" (storePolicy config)
                , textEntry "Store Type" config.storageConfig.storeType
                , textEntry "Message Cap" (mailboxCap config)
                , textEntry "Retention Period" (retentionPeriod config)
                ]


+acceptPolicy : ServerConfig -> String
 acceptPolicy config =
-    if config.defaultAccept then
+    if config.smtpConfig.defaultAccept then
        "All domains"
-            ++ (case config.rejectDomains of
+            ++ (case config.smtpConfig.rejectDomains of
                    Nothing ->
                        ""

@@ -295,7 +303,7 @@ acceptPolicy config =

    else
        "No domains"
-            ++ (case config.acceptDomains of
+            ++ (case config.smtpConfig.acceptDomains of
                    Nothing ->
                        ""

@@ -307,10 +315,11 @@ acceptPolicy config =
               )


+storePolicy : ServerConfig -> String
 storePolicy config =
-    if config.defaultStore then
+    if config.smtpConfig.defaultStore then
        "All domains"
-            ++ (case config.discardDomains of
+            ++ (case config.smtpConfig.discardDomains of
                    Nothing ->
                        ""

@@ -323,7 +332,7 @@ storePolicy config =

    else
        "No domains"
-            ++ (case config.storeDomains of
+            ++ (case config.smtpConfig.storeDomains of
                    Nothing ->
                        ""

@@ -412,23 +421,6 @@ viewMetric metric =
        ]


-viewLiveMetric : String -> (Int -> String) -> Int -> Html a -> Html a
-viewLiveMetric label formatter value graph =
-    div [ class "metric" ]
-        [ div [ class "label" ] [ text label ]
-        , div [ class "value" ] [ text (formatter value) ]
-        , div [ class "graph" ]
-            [ graph
-            , text "(10min)"
-            ]
-        ]
-
-
-graphNull : Html a
-graphNull =
-    div [] []
-
-
 graphSize : Spark.Size
 graphSize =
    { width = 180
--- a/ui/src/Route.elm
+++ b/ui/src/Route.elm
@@ -1,8 +1,5 @@
-module Route exposing (Route(..), fromUrl, href, pushUrl, replaceUrl)
+module Route exposing (Route(..), Router, newRouter)

-import Browser.Navigation as Navigation exposing (Key)
-import Html exposing (Attribute)
-import Html.Attributes as Attr
 import Url exposing (Url)
 import Url.Builder as Builder
 import Url.Parser as Parser exposing ((</>), Parser, map, oneOf, s, string, top)
@@ -17,6 +14,25 @@ type Route
    | Status


+type alias Router =
+    { fromUrl : Url -> Route
+    , toPath : Route -> String
+    }
+
+
+{-| Returns a configured Router.
+-}
+newRouter : String -> Router
+newRouter basePath =
+    let
+        newPath =
+            prepareBasePath basePath
+    in
+    { fromUrl = fromUrl newPath
+    , toPath = toPath newPath
+    }
+
+
 {-| Routes our application handles.
 -}
 routes : List (Parser (Route -> a) a)
@@ -29,10 +45,26 @@ routes =
    ]


+{-| Returns the Route for a given URL.
+-}
+fromUrl : String -> Url -> Route
+fromUrl basePath url =
+    let
+        relative =
+            { url | path = String.replace basePath "" url.path }
+    in
+    case Parser.parse (oneOf routes) relative of
+        Nothing ->
+            Unknown url.path
+
+        Just route ->
+            route
+
+
 {-| Convert route to a URI.
 -}
-routeToPath : Route -> String
-routeToPath page =
+toPath : String -> Route -> String
+toPath basePath page =
    let
        pieces =
            case page of
@@ -54,35 +86,32 @@ routeToPath page =
                Status ->
                    [ "status" ]
    in
-    Builder.absolute pieces []
+    basePath ++ Builder.absolute pieces []


+{-| Make sure basePath starts with a slash and does not have trailing slashes.

-- PUBLIC HELPERS
+"inbucket/" becomes "/inbucket", "" remains ""

-
-href : Route -> Attribute msg
-href route =
-    Attr.href (routeToPath route)
-
-
-replaceUrl : Key -> Route -> Cmd msg
-replaceUrl key =
-    routeToPath >> Navigation.replaceUrl key
-
-
-pushUrl : Key -> Route -> Cmd msg
-pushUrl key =
-    routeToPath >> Navigation.pushUrl key
-
-
-{-| Returns the Route for a given URL.
 -}
-fromUrl : Url -> Route
-fromUrl location =
-    case Parser.parse (oneOf routes) location of
-        Nothing ->
-            Unknown location.path
+prepareBasePath : String -> String
+prepareBasePath path =
+    let
+        stripSlashes str =
+            if String.startsWith "/" str then
+                stripSlashes (String.dropLeft 1 str)

-        Just route ->
-            route
+            else if String.endsWith "/" str then
+                stripSlashes (String.dropRight 1 str)
+
+            else
+                str
+
+        newPath =
+            stripSlashes path
+    in
+    if newPath == "" then
+        ""
+
+    else
+        "/" ++ newPath
--- a/ui/src/Timer.elm
+++ b/ui/src/Timer.elm
@@ -0,0 +1,58 @@
+module Timer exposing (Timer, cancel, empty, replace, schedule)
+
+import Process
+import Task
+
+
+{-| Implements an identity to track an asynchronous timer.
+-}
+type Timer
+    = Empty
+    | Idle Int
+    | Timer Int
+
+
+empty : Timer
+empty =
+    Empty
+
+
+schedule : (Timer -> msg) -> Timer -> Float -> Cmd msg
+schedule message timer millis =
+    Task.perform (always (message timer)) (Process.sleep millis)
+
+
+{-| Replaces the provided timer with a newly created one.
+-}
+replace : Timer -> Timer
+replace previous =
+    case previous of
+        Empty ->
+            Timer 0
+
+        Idle index ->
+            Timer (next index)
+
+        Timer index ->
+            Timer (next index)
+
+
+{-| Cancels the provided timer without creating a replacement.
+-}
+cancel : Timer -> Timer
+cancel previous =
+    case previous of
+        Timer index ->
+            Idle index
+
+        _ ->
+            previous
+
+
+next : Int -> Int
+next index =
+    if index > 2 ^ 30 then
+        0
+
+    else
+        index + 1
--- a/ui/src/mailbox.css
+++ b/ui/src/mailbox.css
@@ -69,7 +69,8 @@
    grid-gap: 1px 20px;
    grid:
      "ctrl mesg" auto
-      "list mesg" 1fr / minmax(200px, 300px) minmax(650px, 1000px);
+      "list mesg" 1fr
+      / minmax(200px, 300px) minmax(650px, auto);
    height: 100%;
  }

--- a/ui/src/main.css
+++ b/ui/src/main.css
@@ -116,23 +116,29 @@ a.button {
  justify-content: center;
  grid-gap: 20px;
  grid-template:
-    "lpad head rpad" auto
+    "head head head" auto
    "lpad page rpad" 1fr
-    "foot foot foot" auto / minmax(20px, auto) 1fr minmax(20px, auto);
-  height: 100vh;
+    "foot foot foot" auto / 1px 1fr 1px;
+  height: auto;
 }

-@media (max-width: 999px) {
+.desktop {
+  display: none;
+}
+
+@media screen and (min-width: 1000px) {
  .app {
+    grid-column-gap: 40px;
    grid-template:
-      "head head head" auto
+      "lpad head rpad" auto
      "lpad page rpad" 1fr
-      "foot foot foot" auto / 1px 1fr 1px;
-    height: auto;
+      "foot foot foot" auto
+      / 1fr minmax(auto, 1300px) 1fr;
+    height: 100vh;
  }

-  .desktop {
-    display: none;
+  td.desktop, th.desktop {
+    display: table-cell;
  }
 }

@@ -217,6 +223,10 @@ h3 {
  padding: 10px !important;
 }

+.modal:focus {
+  outline: none;
+}
+
 /** BUTTONS */

 .button-bar {
--- a/ui/src/monitorMessages.js
+++ b/ui/src/monitorMessages.js
@@ -3,22 +3,55 @@
 customElements.define(
  'monitor-messages',
  class MonitorMessages extends HTMLElement {
+    static get observedAttributes() {
+      return [ 'src' ]
+    }
+
    constructor() {
-      const self = super()
-      // TODO make URI/URL configurable.
-      var uri = '/api/v1/monitor/messages'
-      self._url = ((window.location.protocol === 'https:') ? 'wss://' : 'ws://') + window.location.host + uri
-      self._socket = null
+      super()
+      this._url = null    // Current websocket URL.
+      this._socket = null // Currently open WebSocket.
    }

    connectedCallback() {
+      if (this.hasAttribute('src')) {
+        this.wsOpen(this.getAttribute('src'))
+      }
+    }
+
+    attributeChangedCallback() {
+      // Checking _socket prevents connection attempts prior to connectedCallback().
+      if (this._socket && this.hasAttribute('src')) {
+        this.wsOpen(this.getAttribute('src'))
+      }
+    }
+
+    disconnectedCallback() {
+      this.wsClose()
+    }
+
+    // Connects to WebSocket and registers event listeners.
+    wsOpen(uri) {
+      const url =
+        ((window.location.protocol === 'https:') ? 'wss://' : 'ws://') +
+        window.location.host + uri
+      if (this._socket && url === this._url) {
+        // Already connected to same URL.
+        return
+      }
+      this.wsClose()
+      this._url = url
+
+      console.info("Connecting to WebSocket", url)
+      const ws = new WebSocket(url)
+      this._socket = ws
+
+      // Register event listeners.
      const self = this
-      self._socket = new WebSocket(self._url)
-      var ws = self._socket
-      ws.addEventListener('open', function (e) {
+      ws.addEventListener('open', function (_e) {
        self.dispatchEvent(new CustomEvent('connected', { detail: true }))
      })
-      ws.addEventListener('close', function (e) {
+      ws.addEventListener('close', function (_e) {
        self.dispatchEvent(new CustomEvent('connected', { detail: false }))
      })
      ws.addEventListener('message', function (e) {
@@ -28,11 +61,20 @@ customElements.define(
      })
    }

-    disconnectedCallback() {
-      var ws = this._socket
+    // Closes WebSocket connection.
+    wsClose() {
+      const ws = this._socket
      if (ws) {
        ws.close()
      }
    }
+
+    get src() {
+      return this.getAttribute('src')
+    }
+
+    set src(value) {
+      this.setAttribute('src', value)
+    }
  }
 )
--- a/ui/src/navbar.css
+++ b/ui/src/navbar.css
@@ -50,6 +50,12 @@
  padding: 12px 15px;
 }

+.navbar-dropdown {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
 .navbar-dropdown-button {
  display: none;
 }
@@ -71,6 +77,9 @@ li.navbar-active span,
 .navbar-dropdown-content a {
  color: var(--navbar-color) !important;
  display: block;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
 }

 .navbar-dropdown-content a:hover {
@@ -139,6 +148,7 @@ li.navbar-active span,

  .navbar-dropdown {
    padding: 15px 19px 15px 25px;
+    max-width: 350px;
  }

  .navbar-dropdown-button {
--- a/ui/webpack.config.js
+++ b/ui/webpack.config.js
@@ -6,7 +6,7 @@ module.exports = (env, argv) => {
  const config = {
    output: {
      filename: 'static/[name].[hash:8].js',
-      publicPath: '/',
+      publicPath: '',
    },
    module: {
      rules: [
@@ -54,11 +54,18 @@ module.exports = (env, argv) => {
        template: 'public/index.html',
        favicon: 'public/favicon.png',
      }),
+      new HtmlWebpackPlugin({
+        filename: 'index-dev.html',
+        template: 'public/index-dev.html',
+        favicon: 'public/favicon.png',
+      }),
    ],
    devServer: {
+      historyApiFallback: {
+        index: '/index-dev.html',
+      },
+      index: 'index-dev.html',
      inline: true,
-      historyApiFallback: true,
-      stats: { colors: true },
      overlay: true,
      open: true,
      proxy: [{
@@ -66,6 +73,7 @@ module.exports = (env, argv) => {
        target: 'http://localhost:9000',
        ws: true,
      }],
+      stats: { colors: true },
      watchOptions: {
        ignored: /node_modules/,
      },