Si — lightweight Go HTTP framework

Si is a thin wrapper around chi that provides a convenient Context-based API for handling requests.

Requires Go 1.22+.

Installation

go get -u github.com/revenkroz/si@latest

Usage

package main

import (
	"github.com/revenkroz/si"
	"github.com/revenkroz/si/middleware"
)

func main() {
	server := si.CreateServer(
		"localhost:8080",
		[]si.Middleware{
			middleware.RequestID,
			middleware.Logger,
			middleware.Recoverer,
		},
	)

	server.Get("/", func(ctx *si.Context) {
		ctx.SendString("Hello, world!", 200)
	})

	server.Get("/json", func(ctx *si.Context) {
		ctx.SendJSON(si.Map{
			"message": "Hello, world!",
		}, 200)
	})

	// Subrouter mounted under /hello
	sub := si.NewRouter()
	sub.Get("/{name}", func(ctx *si.Context) {
		name := ctx.ParamString("name")
		ctx.SendString("Hello, "+name+"!", 200)
	})
	server.AddRoute("/hello", sub)

	server.Start()
}

SSE (Server-Sent Events)

server.Get("/events", func(ctx *si.Context) {
	ctx.SSE(func(w *si.SSEWriter) {
		// Detect client disconnect
		done := ctx.Request.Context().Done()

		for i := 0; ; i++ {
			select {
			case <-done:
				return
			default:
				w.JSON("message", si.Map{
					"count": i,
				})
				time.Sleep(time.Second)
			}
		}
	})
})

SSEWriter methods:

Method	Description
Data(data)	Send unnamed event
Event(event, data)	Send named event
JSON(event, v)	Send named event with JSON-encoded data
ID(id)	Set event ID (used by client on reconnect)
Retry(ms)	Set client reconnect interval in milliseconds
Comment(text)	Send comment (useful as keep-alive ping)

Built-in middleware

Middleware	Description
middleware.RequestID	Generates X-Request-Id header (passes through existing value)
middleware.Logger	Logs method, path, status and duration via log/slog
middleware.Recoverer	Recovers from panics, pretty-prints stack trace, returns 500
middleware.CleanPath	Cleans double slashes and /../ segments in request path
middleware.StripSlashes	Silently strips trailing slash and continues routing
middleware.RedirectSlashes	Redirects trailing-slash URLs with 301
middleware.StripPrefix(p)	Strips prefix p from request path

Since Si is built on chi, all chi middleware is fully compatible.

Custom middleware

Any func(http.Handler) http.Handler works as si.Middleware:

func Auth(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.Header.Get("Authorization") == "" {
			http.Error(w, "unauthorized", 401)
			return
		}
		next.ServeHTTP(w, r)
	})
}

Or use si.MW() to write middleware with si.Context:

server.Router.Use(si.MW(func(ctx *si.Context) {
	ctx.WriteHeader("X-Custom", "value")
}))

Context API

Request

Method	Description
ParamString(key)	Path parameter ({key} in pattern)
ParamInt(key)	Path parameter as int
ParamBool(key)	Path parameter as bool
QueryString(key)	Query parameter
QueryStringDefault(key, def)	Query parameter with default
QueryInt(key)	Query parameter as int
QueryIntDefault(key, def)	Query parameter as int with default
QueryBool(key)	Query parameter as bool
HeaderString(key)	Request header
CookieString(key)	Cookie value
ContentType()	Request Content-Type (without parameters)
IsJSON()	Check if request is application/json
IsForm()	Check if request is application/x-www-form-urlencoded
IsMultipartForm()	Check if request is multipart/form-data
BearerToken()	Extract Bearer token from Authorization header
BasicAuth()	Get Basic Auth credentials (user, pass, ok)
IP()	Client IP (respects X-Forwarded-For)
Method()	HTTP method
Host()	Request host
Path()	URL path
GetFormData()	Parsed form data
GetRawContent()	Raw body bytes (re-readable)
UnmarshalJSONBody(v)	Decode JSON body into struct
SetAttribute(key, val)	Store value in request context
GetAttribute(key)	Retrieve value from request context

Response

Method	Description
SendString(data, status)	Send text response
SendJSON(data, status)	Send JSON response
SendHTML(data, status)	Send HTML response
SendBytes(data, status)	Send raw bytes
SendStream(reader, status)	Stream response body
SendFile(path)	Serve a file
SendErrorJSON(msg, status)	Send {"error": {...}} response
NoContent()	Send 204 No Content
Redirect(url, status)	HTTP redirect
SSE(fn)	Start SSE stream (see above)
WriteHeader(key, val)	Set response header
WriteStatus(code)	Write status code
SetCookie(cookie)	Set cookie
SS(data)	Shortcut: SendString(data, 200)
SJ(data)	Shortcut: SendJSON(data, 200)
SB(data)	Shortcut: SendBytes(data, 200)