Add tags for json serialization to settings structs

.gitignore

@@ -13,3 +13,6 @@
 
 # Go workspace file
 go.work
+
+# Lithium specific
+settings.json

main.go

@@ -2,10 +2,13 @@ package main
 
 import (
 	"encoding/json"
-	"github.com/geplauder/lithium/pipelines"
 	"net/http"
 
+	"github.com/geplauder/lithium/pipelines"
+	"github.com/geplauder/lithium/settings"
+	"github.com/geplauder/lithium/storage"
 	"github.com/gorilla/mux"
+	"github.com/spf13/afero"
 )
 
 const Name string = "Lithium"
@@ -16,7 +19,7 @@ type Metadata struct {
 	Version string
 }
 
-func PipelineHandler(pipeline pipelines.IPipeline, w http.ResponseWriter, r *http.Request) {
+func PipelineHandler(pipeline pipelines.IPipeline, storageProvider storage.IStorageProvider, w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 	err := json.NewEncoder(w).Encode(pipeline)
 	if err != nil {
@@ -32,23 +35,33 @@ func IndexHandler(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
-func RegisterPipelineRoutes(r *mux.Router, pipelines []pipelines.IPipeline) {
+func RegisterPipelineRoutes(r *mux.Router, pipelines []pipelines.IPipeline, storageProvider storage.IStorageProvider) {
 	for _, pipeline := range pipelines {
 		r.HandleFunc("/"+pipeline.GetSlug(), func(w http.ResponseWriter, r *http.Request) {
-			PipelineHandler(pipeline, w, r)
+			PipelineHandler(pipeline, storageProvider, w, r)
 		})
 	}
 }
 
 func main() {
+	settings := settings.LoadSettings(afero.NewOsFs())
+
+	var storageProvider storage.IStorageProvider
+
+	if settings.StorageProvider.Type == 0 {
+		storageProvider = storage.GetFileSystemStorageProvider(settings.StorageProvider.BasePath)
+	} else {
+		panic("Invalid file system provided!")
+	}
+
 	pipes := pipelines.LoadPipelines()
 
 	r := mux.NewRouter()
 	r.HandleFunc("/", IndexHandler)
 
-	RegisterPipelineRoutes(r, pipes)
+	RegisterPipelineRoutes(r, pipes, storageProvider)
 
-	err := http.ListenAndServe(":8000", r)
+	err := http.ListenAndServe(settings.Endpoint, r)
 	if err != nil {
 		panic(err)
 	}

main_test.go

@@ -3,12 +3,13 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"github.com/geplauder/lithium/pipelines"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
 	"github.com/bxcodec/faker/v3"
+	"github.com/geplauder/lithium/pipelines"
+	"github.com/geplauder/lithium/storage"
 	"github.com/gorilla/mux"
 	"github.com/stretchr/testify/assert"
 )
@@ -34,7 +35,9 @@ func TestEndpointRoute(t *testing.T) {
 
 	t.Run("Registered pipelines are valid routes", func(t *testing.T) {
 		router := mux.NewRouter()
-		RegisterPipelineRoutes(router, []pipelines.IPipeline{data})
+		fs := storage.GetMemoryStorageProvider()
+
+		RegisterPipelineRoutes(router, []pipelines.IPipeline{data}, fs)
 
 		request, _ := http.NewRequest("GET", "/"+data.Slug, nil)
 		responseRecorder := httptest.NewRecorder()

settings/settings.go

@@ -0,0 +1,61 @@
+package settings
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/afero"
+)
+
+const (
+	Local FileSystemType = iota
+)
+
+type FileSystemType int
+
+type Settings struct {
+	Endpoint        string          `json:"endpoint"`
+	Token           string          `json:"token"`
+	StorageProvider StorageSettings `json:"storage_provider"`
+}
+
+type StorageSettings struct {
+	Type     FileSystemType `json:"type"`
+	BasePath string         `json:"base_path"`
+}
+
+func parseSettings(data []byte) Settings {
+	settings := Settings{}
+
+	json.Unmarshal(data, &settings)
+
+	return settings
+}
+
+func LoadSettings(fileSystem afero.Fs) Settings {
+	workingDirectory, _ := os.Getwd()
+	path := filepath.Join(workingDirectory, "settings.json")
+
+	// Load file and parse file
+	data, err := afero.ReadFile(fileSystem, path)
+
+	if err == nil {
+		return parseSettings(data)
+	}
+
+	// If file does not exist, create default settings
+	defaultSettings := Settings{
+		Endpoint: "127.0.0.1:8000",
+		Token:    "changeme",
+		StorageProvider: StorageSettings{
+			Type:     Local,
+			BasePath: "assets",
+		},
+	}
+
+	serializedSettings, err := json.MarshalIndent(defaultSettings, "", "\t")
+	afero.WriteFile(fileSystem, path, serializedSettings, os.ModePerm)
+
+	return defaultSettings
+}

settings/settings_test.go

@@ -0,0 +1,48 @@
+package settings
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSettingsParsing(t *testing.T) {
+	const file string = `{
+		"endpoint": "0.0.0.0:8000",
+		"token": "foobar",
+		"storage_provider": {
+			"type": 0,
+			"base_path": "assets"
+		}
+	}`
+
+	t.Run("Settings parsing is successful", func(t *testing.T) {
+		settings := parseSettings([]byte(file))
+
+		assert.Equal(t, "0.0.0.0:8000", settings.Endpoint)
+		assert.Equal(t, "foobar", settings.Token)
+		assert.Equal(t, "assets", settings.StorageProvider.BasePath)
+	})
+}
+
+func TestSettingsLoading(t *testing.T) {
+	t.Run("Settings loading creates default settings.json when none is present", func(t *testing.T) {
+		fileSystem := afero.NewMemMapFs()
+		workingDirectory, _ := os.Getwd()
+
+		path := filepath.Join(workingDirectory, "settings.json")
+
+		// Settings file does not exist in the beginning
+		doesFileExist, _ := afero.Exists(fileSystem, path)
+		assert.False(t, doesFileExist)
+
+		LoadSettings(fileSystem)
+
+		// Settings file should be present after calling LoadSettings
+		doesFileExist, _ = afero.Exists(fileSystem, path)
+		assert.True(t, doesFileExist)
+	})
+}

storage/storage.go

@@ -8,8 +8,8 @@ import (
 )
 
 type IStorageProvider interface {
-	storeRaw(bucketName string, objectName string, data []byte) string
-	storeExisting(bucketName string, objectName string, existingFilePath string) string
+	StoreRaw(bucketName string, objectName string, data []byte) string
+	StoreExisting(bucketName string, objectName string, existingFilePath string) string
 }
 
 type FileSystemStorageProvider struct {
@@ -17,7 +17,7 @@ type FileSystemStorageProvider struct {
 	basePath   string
 }
 
-func (sp FileSystemStorageProvider) storeRaw(bucketName string, objectName string, data []byte) string {
+func (sp FileSystemStorageProvider) StoreRaw(bucketName string, objectName string, data []byte) string {
 	directoryPath := filepath.Join(sp.basePath, bucketName)
 
 	sp.fileSystem.MkdirAll(directoryPath, os.ModePerm)
@@ -29,8 +29,25 @@ func (sp FileSystemStorageProvider) storeRaw(bucketName string, objectName strin
 	return filePath
 }
 
-func (sp FileSystemStorageProvider) storeExisting(bucketName string, objectName string, existingFilePath string) string {
+func (sp FileSystemStorageProvider) StoreExisting(bucketName string, objectName string, existingFilePath string) string {
 	bytesRead, _ := afero.ReadFile(sp.fileSystem, existingFilePath)
 
-	return sp.storeRaw(bucketName, objectName, bytesRead)
+	return sp.StoreRaw(bucketName, objectName, bytesRead)
+}
+
+func GetFileSystemStorageProvider(basePath string) FileSystemStorageProvider {
+	wd, _ := os.Getwd()
+
+	return FileSystemStorageProvider{
+		fileSystem: afero.NewBasePathFs(afero.NewOsFs(), filepath.Join(wd, "files")),
+		basePath:   basePath,
+	}
+}
+
+// TODO: Move this out of this file
+func GetMemoryStorageProvider() FileSystemStorageProvider {
+	return FileSystemStorageProvider{
+		fileSystem: afero.NewBasePathFs(afero.NewMemMapFs(), "/"),
+		basePath:   "/tmp/foo/bar",
+	}
 }

storage/storage_test.go

@@ -19,7 +19,7 @@ func TestFileSystemStorageProvider(t *testing.T) {
 			basePath:   "/tmp/foo/bar",
 		}
 
-		finalPath := provider.storeRaw("test", "test.bin", dummyData)
+		finalPath := provider.StoreRaw("test", "test.bin", dummyData)
 		assert.Equal(t, "/tmp/foo/bar/test/test.bin", finalPath)
 
 		exists, _ := afero.Exists(fileSystem, "/tmp/foo/bar/test/test.bin")
@@ -39,7 +39,7 @@ func TestFileSystemStorageProvider(t *testing.T) {
 			basePath:   "/tmp/foo/bar",
 		}
 
-		finalPath := provider.storeExisting("test", "test.bin", "/tmp/existing.bin")
+		finalPath := provider.StoreExisting("test", "test.bin", "/tmp/existing.bin")
 		assert.Equal(t, "/tmp/foo/bar/test/test.bin", finalPath)
 
 		exists, _ := afero.Exists(fileSystem, "/tmp/foo/bar/test/test.bin")