feat: add image upload functionality for articles

- Implemented image upload API in the article service, allowing users to upload images associated with articles.
- Added validation for image size and type, ensuring only supported formats (PNG, JPG, GIF, WebP) are accepted.
- Created a new Aliyun object storage client to handle image storage and retrieval.
- Updated the article handler to include an endpoint for image uploads.
- Enhanced error handling for image upload failures and added relevant error messages.
- Introduced public URL generation for stored images, allowing access via signed tokens.
- Updated localization files to include new messages related to image upload functionality.
- Added tests for image upload and retrieval processes.

server/internal/shared/config/config.go

@@ -181,6 +181,12 @@ func applyEnvOverrides(cfg *Config) {
 	if publicBaseURL, ok := lookupNonEmptyEnv("OBJECT_STORAGE_PUBLIC_BASE_URL"); ok {
 		cfg.ObjectStorage.PublicBaseURL = publicBaseURL
 	}
+	if region, ok := lookupNonEmptyEnv("OBJECT_STORAGE_REGION"); ok {
+		cfg.ObjectStorage.Region = region
+	}
+	if useSSL, ok := lookupBoolEnv("OBJECT_STORAGE_USE_SSL"); ok {
+		cfg.ObjectStorage.UseSSL = useSSL
+	}
 	if apiKey, ok := lookupFirstNonEmptyEnv("SILICONFLOW_API_KEY", "RETRIEVAL_API_KEY", "EMBEDDING_API_KEY", "RERANKER_API_KEY"); ok {
 		cfg.Retrieval.APIKey = apiKey
 	}
@@ -217,3 +223,19 @@ func lookupNonEmptyEnv(key string) (string, bool) {
 
 	return value, true
 }
+
+func lookupBoolEnv(key string) (bool, bool) {
+	value, ok := os.LookupEnv(key)
+	if !ok {
+		return false, false
+	}
+
+	switch strings.ToLower(strings.TrimSpace(value)) {
+	case "1", "true", "yes", "on":
+		return true, true
+	case "0", "false", "no", "off":
+		return false, true
+	default:
+		return false, false
+	}
+}