feat: add support for S3 storage backend (#1080)

Co-authored-by: Alessandro (Ale) Segala <43508+ItalyPaleAle@users.noreply.github.com>

backend/internal/common/env_config.go

@@ -29,6 +29,7 @@ const (
 	DbProviderPostgres      DbProvider = "postgres"
 	MaxMindGeoLiteCityUrl   string     = "https://download.maxmind.com/app/geoip_download?edition_id=GeoLite2-City&license_key=%s&suffix=tar.gz"
 	defaultSqliteConnString string     = "data/pocket-id.db"
+	defaultFsUploadPath     string     = "data/uploads"
 	AppUrl                  string     = "http://localhost:1411"
 )
 
@@ -38,7 +39,14 @@ type EnvConfigSchema struct {
 	AppURL             string     `env:"APP_URL" options:"toLower,trimTrailingSlash"`
 	DbProvider         DbProvider `env:"DB_PROVIDER" options:"toLower"`
 	DbConnectionString string     `env:"DB_CONNECTION_STRING" options:"file"`
+	FileBackend        string     `env:"FILE_BACKEND" options:"toLower"`
 	UploadPath         string     `env:"UPLOAD_PATH"`
+	S3Bucket           string     `env:"S3_BUCKET"`
+	S3Region           string     `env:"S3_REGION"`
+	S3Endpoint         string     `env:"S3_ENDPOINT"`
+	S3AccessKeyID      string     `env:"S3_ACCESS_KEY_ID"`
+	S3SecretAccessKey  string     `env:"S3_SECRET_ACCESS_KEY"`
+	S3ForcePathStyle   bool       `env:"S3_FORCE_PATH_STYLE"`
 	KeysPath           string     `env:"KEYS_PATH"`
 	KeysStorage        string     `env:"KEYS_STORAGE"`
 	EncryptionKey      []byte     `env:"ENCRYPTION_KEY" options:"file"`
@@ -72,30 +80,16 @@ func init() {
 
 func defaultConfig() EnvConfigSchema {
 	return EnvConfigSchema{
-		AppEnv:             "production",
-		LogLevel:           "info",
-		DbProvider:         "sqlite",
-		DbConnectionString: "",
-		UploadPath:         "data/uploads",
-		KeysPath:           "data/keys",
-		KeysStorage:        "", // "database" or "file"
-		EncryptionKey:      nil,
-		AppURL:             AppUrl,
-		Port:               "1411",
-		Host:               "0.0.0.0",
-		UnixSocket:         "",
-		UnixSocketMode:     "",
-		MaxMindLicenseKey:  "",
-		GeoLiteDBPath:      "data/GeoLite2-City.mmdb",
-		GeoLiteDBUrl:       MaxMindGeoLiteCityUrl,
-		LocalIPv6Ranges:    "",
-		UiConfigDisabled:   false,
-		MetricsEnabled:     false,
-		TracingEnabled:     false,
-		TrustProxy:         false,
-		AnalyticsDisabled:  false,
-		AllowDowngrade:     false,
-		InternalAppURL:     "",
+		AppEnv:        "production",
+		LogLevel:      "info",
+		DbProvider:    "sqlite",
+		FileBackend:   "fs",
+		KeysPath:      "data/keys",
+		AppURL:        AppUrl,
+		Port:          "1411",
+		Host:          "0.0.0.0",
+		GeoLiteDBPath: "data/GeoLite2-City.mmdb",
+		GeoLiteDBUrl:  MaxMindGeoLiteCityUrl,
 	}
 }
 
@@ -181,6 +175,19 @@ func validateEnvConfig(config *EnvConfigSchema) error {
 		return fmt.Errorf("invalid value for KEYS_STORAGE: %s", config.KeysStorage)
 	}
 
+	switch config.FileBackend {
+	case "s3":
+		if config.KeysStorage == "file" {
+			return errors.New("KEYS_STORAGE cannot be 'file' when FILE_BACKEND is 's3'")
+		}
+	case "", "fs":
+		if config.UploadPath == "" {
+			config.UploadPath = defaultFsUploadPath
+		}
+	default:
+		return errors.New("invalid FILE_BACKEND value. Must be 'fs' or 's3'")
+	}
+
 	// Validate LOCAL_IPV6_RANGES
 	ranges := strings.Split(config.LocalIPv6Ranges, ",")
 	for _, rangeStr := range ranges {

backend/internal/common/env_config_test.go

@@ -208,6 +208,44 @@ func TestParseEnvConfig(t *testing.T) {
 		assert.Equal(t, "8080", EnvConfig.Port)
 		assert.Equal(t, "localhost", EnvConfig.Host) // lowercased
 	})
+
+	t.Run("should normalize file backend and default upload path", func(t *testing.T) {
+		EnvConfig = defaultConfig()
+		t.Setenv("DB_PROVIDER", "sqlite")
+		t.Setenv("DB_CONNECTION_STRING", "file:test.db")
+		t.Setenv("APP_URL", "http://localhost:3000")
+		t.Setenv("FILE_BACKEND", "FS")
+		t.Setenv("UPLOAD_PATH", "")
+
+		err := parseEnvConfig()
+		require.NoError(t, err)
+		assert.Equal(t, "fs", EnvConfig.FileBackend)
+		assert.Equal(t, defaultFsUploadPath, EnvConfig.UploadPath)
+	})
+
+	t.Run("should fail when FILE_BACKEND is s3 but keys are stored on filesystem", func(t *testing.T) {
+		EnvConfig = defaultConfig()
+		t.Setenv("DB_PROVIDER", "sqlite")
+		t.Setenv("DB_CONNECTION_STRING", "file:test.db")
+		t.Setenv("APP_URL", "http://localhost:3000")
+		t.Setenv("FILE_BACKEND", "s3")
+
+		err := parseEnvConfig()
+		require.Error(t, err)
+		assert.ErrorContains(t, err, "KEYS_STORAGE cannot be 'file' when FILE_BACKEND is 's3'")
+	})
+
+	t.Run("should fail with invalid FILE_BACKEND value", func(t *testing.T) {
+		EnvConfig = defaultConfig()
+		t.Setenv("DB_PROVIDER", "sqlite")
+		t.Setenv("DB_CONNECTION_STRING", "file:test.db")
+		t.Setenv("APP_URL", "http://localhost:3000")
+		t.Setenv("FILE_BACKEND", "invalid")
+
+		err := parseEnvConfig()
+		require.Error(t, err)
+		assert.ErrorContains(t, err, "invalid FILE_BACKEND value")
+	})
 }
 
 func TestPrepareEnvConfig_FileBasedAndToLower(t *testing.T) {