feat: implement plugin loading system

- Add modules/plugins/loader.go to load .so plugins from plugins directory
- Add modules/setting/plugins.go for [plugins] configuration section
- Wire up plugin loading before DB init so plugins can register models
- Wire up plugin migrations and initialization after DB init
- Register plugin routes in web.go

Plugins can now be loaded at runtime by placing .so files in the plugins
directory and enabling [plugins] ENABLED = true in app.ini.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

modules/plugins/loader.go

@@ -0,0 +1,107 @@
+// Copyright 2026 MarketAlly. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package plugins
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"plugin"
+
+	"code.gitcaddy.com/server/modules/log"
+	"code.gitcaddy.com/server/modules/setting"
+)
+
+// LoadAll loads all plugins from the configured plugin directory
+func LoadAll() error {
+	if !setting.Plugins.Enabled {
+		log.Info("Plugin system is disabled")
+		return nil
+	}
+
+	pluginDir := setting.Plugins.Path
+	if pluginDir == "" {
+		pluginDir = filepath.Join(setting.AppDataPath, "plugins")
+	}
+
+	// Check if plugin directory exists
+	info, err := os.Stat(pluginDir)
+	if os.IsNotExist(err) {
+		log.Info("Plugin directory does not exist: %s", pluginDir)
+		return nil
+	}
+	if err != nil {
+		return fmt.Errorf("failed to stat plugin directory: %w", err)
+	}
+	if !info.IsDir() {
+		return fmt.Errorf("plugin path is not a directory: %s", pluginDir)
+	}
+
+	log.Info("Loading plugins from: %s", pluginDir)
+
+	// Find all .so files in the plugin directory
+	entries, err := os.ReadDir(pluginDir)
+	if err != nil {
+		return fmt.Errorf("failed to read plugin directory: %w", err)
+	}
+
+	loadedCount := 0
+	for _, entry := range entries {
+		if entry.IsDir() {
+			continue
+		}
+
+		name := entry.Name()
+		if filepath.Ext(name) != ".so" {
+			continue
+		}
+
+		pluginPath := filepath.Join(pluginDir, name)
+		if err := loadPlugin(pluginPath); err != nil {
+			log.Error("Failed to load plugin %s: %v", name, err)
+			// Continue loading other plugins
+			continue
+		}
+		loadedCount++
+	}
+
+	log.Info("Loaded %d plugin(s)", loadedCount)
+	return nil
+}
+
+// loadPlugin loads a single plugin from a .so file
+func loadPlugin(path string) error {
+	log.Info("Loading plugin: %s", path)
+
+	// Open the plugin
+	p, err := plugin.Open(path)
+	if err != nil {
+		return fmt.Errorf("failed to open plugin: %w", err)
+	}
+
+	// Look for the Plugin symbol
+	sym, err := p.Lookup("Plugin")
+	if err != nil {
+		return fmt.Errorf("plugin does not export 'Plugin' symbol: %w", err)
+	}
+
+	// The Plugin symbol should be a pointer to a Plugin interface implementation
+	plug, ok := sym.(*Plugin)
+	if !ok {
+		// Try to see if it's the interface directly
+		plugDirect, ok := sym.(Plugin)
+		if !ok {
+			return fmt.Errorf("Plugin symbol is not a plugins.Plugin (got %T)", sym)
+		}
+		Register(plugDirect)
+		return nil
+	}
+
+	if plug == nil || *plug == nil {
+		return fmt.Errorf("Plugin symbol is nil")
+	}
+
+	Register(*plug)
+	return nil
+}

modules/plugins/plugin.go

@@ -6,7 +6,6 @@ package plugins
 import (
 	"context"
 
-	"github.com/go-chi/chi/v5"
 	"xorm.io/xorm"
 )
 
@@ -44,7 +43,8 @@ type WebRoutesPlugin interface {
 	Plugin
 
 	// RegisterWebRoutes adds routes to the web UI router
-	RegisterWebRoutes(m chi.Router)
+	// The router is a *web.Router from the gitcaddy server
+	RegisterWebRoutes(m any)
 }
 
 // APIRoutesPlugin is implemented by plugins that add API routes
@@ -52,7 +52,8 @@ type APIRoutesPlugin interface {
 	Plugin
 
 	// RegisterAPIRoutes adds routes to the API router
-	RegisterAPIRoutes(m chi.Router)
+	// The router is a *web.Router from the gitcaddy server
+	RegisterAPIRoutes(m any)
 }
 
 // RepoRoutesPlugin is implemented by plugins that add per-repository routes
@@ -60,10 +61,12 @@ type RepoRoutesPlugin interface {
 	Plugin
 
 	// RegisterRepoWebRoutes adds routes under /{owner}/{repo}/
-	RegisterRepoWebRoutes(m chi.Router)
+	// The router is a *web.Router from the gitcaddy server
+	RegisterRepoWebRoutes(m any)
 
 	// RegisterRepoAPIRoutes adds routes under /api/v1/repos/{owner}/{repo}/
-	RegisterRepoAPIRoutes(m chi.Router)
+	// The router is a *web.Router from the gitcaddy server
+	RegisterRepoAPIRoutes(m any)
 }
 
 // LicensedPlugin is implemented by plugins that require a license

modules/plugins/registry.go

@@ -9,7 +9,6 @@ import (
 
 	"code.gitcaddy.com/server/modules/log"
 
-	"github.com/go-chi/chi/v5"
 	"xorm.io/xorm"
 )
 
@@ -126,7 +125,7 @@ func MigrateAll(ctx context.Context, x *xorm.Engine) error {
 }
 
 // RegisterWebRoutes registers web UI routes from all plugins
-func RegisterWebRoutes(m chi.Router) {
+func RegisterWebRoutes(m any) {
 	registryLock.RLock()
 	defer registryLock.RUnlock()
 
@@ -139,7 +138,7 @@ func RegisterWebRoutes(m chi.Router) {
 }
 
 // RegisterAPIRoutes registers API routes from all plugins
-func RegisterAPIRoutes(m chi.Router) {
+func RegisterAPIRoutes(m any) {
 	registryLock.RLock()
 	defer registryLock.RUnlock()
 
@@ -152,7 +151,7 @@ func RegisterAPIRoutes(m chi.Router) {
 }
 
 // RegisterRepoWebRoutes registers per-repository web routes from all plugins
-func RegisterRepoWebRoutes(m chi.Router) {
+func RegisterRepoWebRoutes(m any) {
 	registryLock.RLock()
 	defer registryLock.RUnlock()
 
@@ -165,7 +164,7 @@ func RegisterRepoWebRoutes(m chi.Router) {
 }
 
 // RegisterRepoAPIRoutes registers per-repository API routes from all plugins
-func RegisterRepoAPIRoutes(m chi.Router) {
+func RegisterRepoAPIRoutes(m any) {
 	registryLock.RLock()
 	defer registryLock.RUnlock()
 

modules/setting/plugins.go

@@ -0,0 +1,21 @@
+// Copyright 2026 MarketAlly. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package setting
+
+// Plugins settings
+var (
+	Plugins = struct {
+		Enabled bool
+		Path    string
+	}{
+		Enabled: false, // Disabled by default
+		Path:    "",    // Empty means default to APP_DATA_PATH/plugins
+	}
+)
+
+func loadPluginsFrom(rootCfg ConfigProvider) {
+	sec := rootCfg.Section("plugins")
+	Plugins.Enabled = sec.Key("ENABLED").MustBool(false)
+	Plugins.Path = sec.Key("PATH").MustString("")
+}

modules/setting/setting.go

@@ -150,6 +150,7 @@ func loadCommonSettingsFrom(cfg ConfigProvider) error {
 	loadMarkupFrom(cfg)
 	loadGlobalLockFrom(cfg)
 	loadOtherFrom(cfg)
+	loadPluginsFrom(cfg)
 	return nil
 }
 

routers/init.go

@@ -12,6 +12,7 @@ import (
 	"code.gitcaddy.com/server/models"
 	ai_model "code.gitcaddy.com/server/models/ai"
 	authmodel "code.gitcaddy.com/server/models/auth"
+	"code.gitcaddy.com/server/models/db"
 	"code.gitcaddy.com/server/modules/cache"
 	"code.gitcaddy.com/server/modules/eventsource"
 	"code.gitcaddy.com/server/modules/git"
@@ -20,6 +21,7 @@ import (
 	"code.gitcaddy.com/server/modules/log"
 	"code.gitcaddy.com/server/modules/markup"
 	"code.gitcaddy.com/server/modules/markup/external"
+	"code.gitcaddy.com/server/modules/plugins"
 	"code.gitcaddy.com/server/modules/setting"
 	"code.gitcaddy.com/server/modules/ssh"
 	"code.gitcaddy.com/server/modules/storage"
@@ -58,6 +60,8 @@ import (
 	"code.gitcaddy.com/server/services/task"
 	"code.gitcaddy.com/server/services/uinotification"
 	"code.gitcaddy.com/server/services/webhook"
+
+	"xorm.io/xorm"
 )
 
 func mustInit(fn func() error) {
@@ -144,8 +148,22 @@ func InitWebInstalled(ctx context.Context) {
 		log.Fatal("SQLite3 support is disabled, but it is used for database setting. Please get or build a Gitea release with SQLite3 support.")
 	}
 
+	// Load plugins before DB init so they can register their models
+	mustInit(plugins.LoadAll)
+
 	mustInitCtx(ctx, common.InitDBEngine)
 	log.Info("ORM engine initialization successful!")
+
+	// Run plugin migrations after DB init
+	if err := plugins.MigrateAll(ctx, db.GetEngine(ctx).(*xorm.Engine)); err != nil {
+		log.Fatal("Plugin migrations failed: %v", err)
+	}
+
+	// Initialize all plugins
+	if err := plugins.InitAll(ctx); err != nil {
+		log.Fatal("Plugin initialization failed: %v", err)
+	}
+
 	mustInit(system.Init)
 	mustInitCtx(ctx, oauth2.Init)
 	mustInitCtx(ctx, oauth2_provider.Init)

routers/web/web.go

@@ -15,6 +15,7 @@ import (
 	"code.gitcaddy.com/server/modules/graceful"
 	"code.gitcaddy.com/server/modules/log"
 	"code.gitcaddy.com/server/modules/metrics"
+	"code.gitcaddy.com/server/modules/plugins"
 	"code.gitcaddy.com/server/modules/public"
 	"code.gitcaddy.com/server/modules/setting"
 	"code.gitcaddy.com/server/modules/storage"
@@ -1799,6 +1800,14 @@ func registerWebRoutes(m *web.Router) {
 		})
 	}
 
+	// Register plugin web routes
+	plugins.RegisterWebRoutes(m)
+
+	// Register plugin repo routes (mounted under /{username}/{reponame})
+	m.Group("/{username}/{reponame}", func() {
+		plugins.RegisterRepoWebRoutes(m)
+	}, optSignIn, context.RepoAssignment, repo.MustBeNotEmpty)
+
 	m.NotFound(func(w http.ResponseWriter, req *http.Request) {
 		ctx := context.GetWebContext(req.Context())
 		defer routing.RecordFuncInfo(ctx, routing.GetFuncInfo(ctx.NotFound, "WebNotFound"))()