Improve docs

README.md

@@ -18,7 +18,20 @@ Assets in `themes/<name>/assets/*` are served by the HTTP server at
 
 ## Plugins
 
-Lua plugins are supported. They can be dropped in `plugins/<name>/main.lua`.
+Plugins can be written in Go or in Lua and live in `plugins/<name>/`.
+
+Plugins can provide their own templates in `plugins/<name>/public/*.html`.
+Assets in `plugins/<name>/public/assets/*` are served by the HTTP server at
+`/plugins/<name>/assets/*`.
+
+### Go plugins
+
+They can use the [Go plugin helpers] and need to be included at compile-time in
+`cmd/koushin/main.go`.
+
+### Lua plugins
+
+The entry point is at `plugins/<name>/main.lua`.
 
 API:
 
@@ -28,15 +41,14 @@ API:
 * `koushin.set_route(method, path, f)`: register a new HTTP route, `f` will be
   called with the HTTP context
 
-Plugins can provide their own templates in `plugins/<name>/public/*.html`.
-Assets in `plugins/<name>/public/assets/*` are served by the HTTP server at
-`/plugins/<name>/assets/*`.
-
 ## Contributing
 
-Send patches [on the mailing list](https://lists.sr.ht/~sircmpwn/koushin),
+Send patches on the [mailing list], report bugs on the [issue tracker].
-report bugs [on the issue tracker](https://todo.sr.ht/~sircmpwn/koushin).
 
 ## License
 
 MIT
+
+[Go plugin helpers]: https://godoc.org/git.sr.ht/~emersion/koushin#GoPlugin
+[mailing list]: https://lists.sr.ht/~sircmpwn/koushin
+[issue tracker]: https://todo.sr.ht/~sircmpwn/koushin

plugin_go.go

@@ -54,6 +54,13 @@ type goPluginRoute struct {
 	Handler echo.HandlerFunc
 }
 
+// GoPlugin is a helper to create Go plugins.
+//
+// Use this struct to define your plugin, then call RegisterPlugin:
+//
+//     p := GoPlugin{Name: "my-plugin"}
+//     // Define routes, template functions, etc
+//     koushin.RegisterPlugin(p.Plugin())
 type GoPlugin struct {
 	Name string
 
@@ -62,6 +69,10 @@ type GoPlugin struct {
 	templateFuncs template.FuncMap
 }
 
+// AddRoute registers a new HTTP route.
+//
+// The echo.Context passed to the HTTP handler can be type-asserted to
+// *koushin.Context.
 func (p *GoPlugin) AddRoute(method, path string, handler echo.HandlerFunc) {
 	p.routes = append(p.routes, goPluginRoute{method, path, handler})
 }
@@ -82,6 +93,7 @@ func (p *GoPlugin) PUT(path string, handler echo.HandlerFunc) {
 	p.AddRoute(http.MethodPut, path, handler)
 }
 
+// TemplateFuncs registers new template functions.
 func (p *GoPlugin) TemplateFuncs(funcs template.FuncMap) {
 	if p.templateFuncs == nil {
 		p.templateFuncs = make(template.FuncMap, len(funcs))
@@ -92,6 +104,7 @@ func (p *GoPlugin) TemplateFuncs(funcs template.FuncMap) {
 	}
 }
 
+// Plugin returns an object implementing Plugin.
 func (p *GoPlugin) Plugin() Plugin {
 	return &goPlugin{p}
 }

plugins/base/handlers.go

@@ -11,8 +11,8 @@ import (
 
 	"git.sr.ht/~emersion/koushin"
 	"github.com/emersion/go-imap"
-	imapclient "github.com/emersion/go-imap/client"
 	imapmove "github.com/emersion/go-imap-move"
+	imapclient "github.com/emersion/go-imap/client"
 	"github.com/emersion/go-message"
 	"github.com/emersion/go-smtp"
 	"github.com/labstack/echo/v4"