Implement Setup() function for providers, cleanup

Implemented a much-needed Setup() function for providers to implement,
which (as demonstrated in the backblaze provider) allows for
authentication in advance of needing to make calls to remote locations.
This could also be used to create a directory or perform some other
sanity check required for the provider to work. So far, haven't noticed
any performance impacts from this approach, besides not needing to auth
each time we make a request.

files/backblaze.go

@@ -45,37 +45,42 @@ type BackblazeBucketInfoPayload struct {
 }
 
 // Call Backblaze API endpoint to authorize and gather facts.
-func (bp *BackblazeProvider) Authorize(appKeyId string, appKey string) error {
+func (bp *BackblazeProvider) Setup(args map[string]string) bool {
+	applicationKeyId := args["applicationKeyId"]
+	applicationKey := args["applicationKey"]
+
 	client := &http.Client{}
 	req, err := http.NewRequest("GET",
 		"https://api.backblazeb2.com/b2api/v2/b2_authorize_account",
 		nil)
 	if err != nil {
-		return err
+		return false
 	}
-	req.SetBasicAuth(appKeyId, appKey)
+	req.SetBasicAuth(applicationKeyId, applicationKey)
 	resp, err := client.Do(req)
 	if err != nil {
-		return err
+		return false
 	}
 	defer resp.Body.Close()
 	body, err := ioutil.ReadAll(resp.Body)
+
 	if err != nil {
-		return err
+		return false
 	}
 
 	var data BackblazeAuthPayload
 
 	err = json.Unmarshal(body, &data)
 	if err != nil {
-		return err
+		return false
 	}
+
 	bp.Authentication = data.AuthToken
 	bp.Location = data.ApiUrl
 	bp.Name = data.AccountId
 	bp.DownloadLocation = data.DownloadUrl
-	
-	return nil
+
+	return true
 }
 
 func (bp *BackblazeProvider) GetDirectory(path string) Directory {
@@ -131,10 +136,22 @@ func (bp *BackblazeProvider) ViewFile(path string, w io.Writer) {
 
 	req, err := http.NewRequest("POST", bp.Location + "/b2api/v2/b2_list_buckets",
 		bytes.NewBuffer([]byte(bucketIdPayload)))
+	if err != nil {
+		fmt.Println(err.Error())
+		return
+	}
 	req.Header.Add("Authorization", bp.Authentication)
 
 	res, err := client.Do(req)
+	if err != nil {
+		fmt.Println(err.Error())
+		return
+	}
 	bucketData, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		fmt.Println(err.Error())
+		return
+	}
 
 	var data BackblazeBucketInfoPayload
 	json.Unmarshal(bucketData, &data)
@@ -169,4 +186,8 @@ func (bp *BackblazeProvider) SaveFile(contents []byte, path string) bool {
 
 func (bp *BackblazeProvider) DetermineType(path string) string {
 	return "file"
+}
+
+func (bp *BackblazeProvider) GetProviderConfig() FileProvider {
+	return ProviderConfig[bp.Name]
 }

files/disk.go

@@ -11,6 +11,10 @@ type DiskProvider struct{
 	FileProvider
 }
 
+func (dp *DiskProvider) Setup(args map[string]string) bool {
+	return true
+}
+
 func (dp *DiskProvider) GetDirectory(path string) Directory {
 	rp := strings.Join([]string{dp.Location,path}, "/")
 	fileDir, err := ioutil.ReadDir(rp)

files/fileprovider.go

@@ -1,7 +1,6 @@
 package files
 
 import (
-	"fmt"
 	"io"
 )
 
@@ -24,44 +23,24 @@ type FileInfo struct {
 	Extension   string
 }
 
-var Providers map[string]FileProvider
-
 type FileContents struct {
 	Content []byte
 	IsUrl   bool
 }
 
 type FileProviderInterface interface {
+	Setup(args map[string]string) bool
 	GetDirectory(path string) Directory
 	ViewFile(path string, w io.Writer)
 	SaveFile(contents []byte, path string) bool
 	DetermineType(path string) string
 }
 
-func TranslateProvider(codename string, i *FileProviderInterface) {
-	provider := Providers[codename]
-	if codename == "disk" {
-		*i = &DiskProvider{provider,}
-		return
-	}
-	/*
-	 * @TODO: It would be ideal if the authorization with Backblaze was done before
-	 * actually needing to use it, ideally during the startup step.
-	 */
-	if codename == "backblaze" {
-		bbProv := &BackblazeProvider{provider, provider.Config["bucket"], ""}
-
-		err := bbProv.Authorize(provider.Config["appKeyId"], provider.Config["appId"])
-		if err != nil {
-			fmt.Println(err.Error())
-		}
-		*i = bbProv
-		return
-	}
-	*i = FileProvider{}
+/** DO NOT USE THESE DEFAULTS **/
+func (f FileProvider) Setup(args map[string]string) bool {
+	return false
 }
 
-/** DO NOT USE THESE DEFAULTS **/
 func (f FileProvider) GetDirectory(path string) Directory {
 	return Directory{}
 }
@@ -77,3 +56,4 @@ func (f FileProvider) SaveFile(contents []byte, path string) bool {
 func (f FileProvider) DetermineType(path string) string {
 	return ""
 }
+

files/fileutils.go

@@ -0,0 +1,36 @@
+package files
+
+import "fmt"
+
+var ProviderConfig map[string]FileProvider
+var Providers map[string]*FileProviderInterface
+
+func TranslateProvider(codename string, i *FileProviderInterface) {
+	provider := ProviderConfig[codename]
+	if codename == "disk" {
+		*i = &DiskProvider{provider,}
+		return
+	}
+
+	if codename == "backblaze" {
+		bbProv := &BackblazeProvider{provider, provider.Config["bucket"], ""}
+		*i = bbProv
+		return
+	}
+	*i = FileProvider{}
+}
+
+func SetupProviders() {
+	Providers = make(map[string]*FileProviderInterface)
+	for name, provider := range ProviderConfig {
+		var i FileProviderInterface
+		TranslateProvider(name, &i)
+		success := i.Setup(provider.Config)
+		if !success {
+			fmt.Printf("%s failed to initialize\n", name)
+		} else {
+			Providers[name] = &i
+			fmt.Printf("%s initialized successfully\n", name)
+		}
+	}
+}

router/filerouter.go

@@ -14,8 +14,7 @@ func HandleProvider() common.Handler {
 		vars := mux.Vars(r)
 		if r.Method == "GET" {
 			providerCodename := vars["provider"]
-			var provider files.FileProviderInterface
-			files.TranslateProvider(providerCodename, &provider)
+			provider := *files.Providers[providerCodename]
 
 			fileList := provider.GetDirectory("")
 			if vars["file"] != "" {

webserver.go

@@ -1,9 +1,3 @@
-/* webserver.go
- *
- * This is the webserver handler for Pogo, and handles
- * all incoming connections, including authentication.
- */
-
 package main
 
 import (
@@ -34,10 +28,11 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
-	err = yaml.Unmarshal(file, &files.Providers)
+	err = yaml.Unmarshal(file, &files.ProviderConfig)
 	if err != nil {
 		panic(err)
 	}
+	files.SetupProviders()
 
 	r := router.Init()
 	fmt.Println("Your NAS instance is live on port :3000")