storage: Make type/params configurable for #88

pkg/config/config.go

@@ -69,10 +69,11 @@ type Web struct {
 
 // Storage contains the mail store configuration.
 type Storage struct {
-	Path            string        `required:"true" default:"/tmp/inbucket" desc:"Mail store path"`
-	RetentionPeriod time.Duration `required:"true" default:"24h" desc:"Duration to retain messages"`
-	RetentionSleep  time.Duration `required:"true" default:"50ms" desc:"Duration to sleep between mailboxes"`
-	MailboxMsgCap   int           `required:"true" default:"500" desc:"Maximum messages per mailbox"`
+	Type            string            `required:"true" default:"memory" desc:"Storage impl: file or memory"`
+	Params          map[string]string `desc:"Storage impl parameters, see docs."`
+	RetentionPeriod time.Duration     `required:"true" default:"24h" desc:"Duration to retain messages"`
+	RetentionSleep  time.Duration     `required:"true" default:"50ms" desc:"Duration to sleep between mailboxes"`
+	MailboxMsgCap   int               `required:"true" default:"500" desc:"Maximum messages per mailbox"`
 }
 
 // Process loads and parses configuration from the environment.

pkg/storage/file/fstore.go

@@ -48,11 +48,10 @@ type Store struct {
 }
 
 // New creates a new DataStore object using the specified path
-func New(cfg config.Storage) storage.Store {
-	path := cfg.Path
+func New(cfg config.Storage) (storage.Store, error) {
+	path := cfg.Params["path"]
 	if path == "" {
-		log.Errorf("No value configured for datastore path")
-		return nil
+		return nil, fmt.Errorf("'path' parameter not specified")
 	}
 	mailPath := filepath.Join(path, "mail")
 	if _, err := os.Stat(mailPath); err != nil {
@@ -61,7 +60,7 @@ func New(cfg config.Storage) storage.Store {
 			log.Errorf("Error creating dir %q: %v", mailPath, err)
 		}
 	}
-	return &Store{path: path, mailPath: mailPath, messageCap: cfg.MailboxMsgCap}
+	return &Store{path: path, mailPath: mailPath, messageCap: cfg.MailboxMsgCap}, nil
 }
 
 // AddMessage adds a message to the specified mailbox.

pkg/storage/file/fstore_test.go

@@ -265,13 +265,18 @@ func setupDataStore(cfg config.Storage) (*Store, *bytes.Buffer) {
 	if err != nil {
 		panic(err)
 	}
-
-	// Capture log output
+	// Capture log output.
 	buf := new(bytes.Buffer)
 	log.SetOutput(buf)
-
-	cfg.Path = path
-	return New(cfg).(*Store), buf
+	if cfg.Params == nil {
+		cfg.Params = make(map[string]string)
+	}
+	cfg.Params["path"] = path
+	s, err := New(cfg)
+	if err != nil {
+		panic(err)
+	}
+	return s.(*Store), buf
 }
 
 // deliverMessage creates and delivers a message to the specific mailbox, returning

pkg/storage/mem/store.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 	"sync"
 
+	"github.com/jhillyerd/inbucket/pkg/config"
 	"github.com/jhillyerd/inbucket/pkg/storage"
 )
 
@@ -25,10 +26,10 @@ type mbox struct {
 var _ storage.Store = &Store{}
 
 // New returns an emtpy memory store.
-func New() *Store {
+func New(cfg config.Storage) (storage.Store, error) {
 	return &Store{
 		boxes: make(map[string]*mbox),
-	}
+	}, nil
 }
 
 // AddMessage stores the message, message ID and Size will be ignored.

pkg/storage/mem/store_test.go

@@ -3,6 +3,7 @@ package mem
 import (
 	"testing"
 
+	"github.com/jhillyerd/inbucket/pkg/config"
 	"github.com/jhillyerd/inbucket/pkg/storage"
 	"github.com/jhillyerd/inbucket/pkg/test"
 )
@@ -10,7 +11,7 @@ import (
 // TestSuite runs storage package test suite on file store.
 func TestSuite(t *testing.T) {
 	test.StoreSuite(t, func() (storage.Store, func(), error) {
-		s := New()
+		s, _ := New(config.Storage{})
 		destroy := func() {}
 		return s, destroy, nil
 	})

pkg/storage/storage.go

@@ -3,9 +3,12 @@ package storage
 
 import (
 	"errors"
+	"fmt"
 	"io"
 	"net/mail"
 	"time"
+
+	"github.com/jhillyerd/inbucket/pkg/config"
 )
 
 var (
@@ -14,6 +17,9 @@ var (
 
 	// ErrNotWritable indicates the message is closed; no longer writable
 	ErrNotWritable = errors.New("Message not writable")
+
+	// Constructors tracks registered storage constructors
+	Constructors = make(map[string]func(config.Storage) (Store, error))
 )
 
 // Store is the interface Inbucket uses to interact with storage implementations.
@@ -38,3 +44,11 @@ type Message interface {
 	Source() (io.ReadCloser, error)
 	Size() int64
 }
+
+// FromConfig creates an instance of the Store based on the provided configuration.
+func FromConfig(c config.Storage) (store Store, err error) {
+	if cf := Constructors[c.Type]; cf != nil {
+		return cf(c)
+	}
+	return nil, fmt.Errorf("unknown storage type configured: %q", c.Type)
+}