ui: Move REST API calls into new Api module

ui/src/Api.elm

@@ -0,0 +1,101 @@
+module Api exposing
+    ( deleteMessage
+    , getGreeting
+    , getHeaderList
+    , getMessage
+    , getServerConfig
+    , getServerMetrics
+    , markMessageSeen
+    , purgeMailbox
+    )
+
+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 Http
+import HttpUtil
+import Json.Decode as Decode
+import Json.Encode as Encode
+import Url.Builder
+
+
+type alias DataResult msg data =
+    Result Http.Error data -> msg
+
+
+type alias HttpResult msg =
+    Result Http.Error () -> msg
+
+
+{-| Builds a public REST API URL (see wiki).
+-}
+apiV1Url : List String -> String
+apiV1Url elements =
+    Url.Builder.absolute ([ "api", "v1" ] ++ elements) []
+
+
+{-| 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 =
+    Http.get
+        { url = apiV1Url [ "mailbox", mailboxName ]
+        , expect = Http.expectJson msg (Decode.list MessageHeader.decoder)
+        }
+
+
+getGreeting : DataResult msg String -> Cmd msg
+getGreeting msg =
+    Http.get
+        { url = serveUrl [ "greeting" ]
+        , expect = Http.expectString msg
+        }
+
+
+getMessage : DataResult msg Message -> String -> String -> Cmd msg
+getMessage msg mailboxName id =
+    Http.get
+        { url = serveUrl [ "m", mailboxName, id ]
+        , expect = Http.expectJson msg Message.decoder
+        }
+
+
+getServerConfig : DataResult msg ServerConfig -> Cmd msg
+getServerConfig msg =
+    Http.get
+        { url = serveUrl [ "status" ]
+        , expect = Http.expectJson msg ServerConfig.decoder
+        }
+
+
+getServerMetrics : DataResult msg Metrics -> Cmd msg
+getServerMetrics msg =
+    Http.get
+        { url = Url.Builder.absolute [ "debug", "vars" ] []
+        , expect = Http.expectJson msg Metrics.decoder
+        }
+
+
+markMessageSeen : HttpResult msg -> String -> String -> Cmd msg
+markMessageSeen 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 ])
+
+
+purgeMailbox : HttpResult msg -> String -> Cmd msg
+purgeMailbox msg mailboxName =
+    HttpUtil.delete msg (apiV1Url [ "mailbox", mailboxName ])