Routing

Lightning uses a trie-based router that resolves routes by HTTP method and path. You register routes on an *Application value returned by lightning.NewApp() or lightning.DefaultApp().

Registering routes

Each HTTP method has a dedicated registration function. Pass the URL pattern as the first argument, then one or more handler functions.

app := lightning.NewApp()

app.Get("/users", listUsers)
app.Post("/users", createUser)
app.Put("/users/:id", replaceUser)
app.Patch("/users/:id", updateUser)
app.Delete("/users/:id", deleteUser)
app.Head("/users/:id", headUser)
app.Options("/users", optionsUsers)

All handler functions have the signature func(*lightning.Context).

Full example

package main

import "github.com/go-labx/lightning"

func main() {
    app := lightning.NewApp()

    app.Get("/", func(ctx *lightning.Context) {
        ctx.Text(lightning.StatusOK, "welcome")
    })

    app.Post("/articles", func(ctx *lightning.Context) {
        // create article
        ctx.JSON(lightning.StatusOK, lightning.Map{"status": "created"})
    })

    app.Put("/articles/:id", func(ctx *lightning.Context) {
        // replace article
        ctx.JSON(lightning.StatusOK, lightning.Map{"status": "replaced"})
    })

    app.Patch("/articles/:id/title", func(ctx *lightning.Context) {
        // update title only
        ctx.JSON(lightning.StatusOK, lightning.Map{"status": "updated"})
    })

    app.Delete("/articles/:id", func(ctx *lightning.Context) {
        // delete article
        ctx.JSON(lightning.StatusOK, lightning.Map{"status": "deleted"})
    })

    app.Run()
}

URL parameters

Prefix a path segment with : to make it a named parameter. Lightning captures the segment and makes it available via ctx.Param.

/users/:id          → matches /users/42
/posts/:slug/edit   → matches /posts/hello-world/edit

Reading parameters

Method	Returns
`ctx.Param(key string) string`	Raw string value
`ctx.ParamInt(key string) (int, error)`	Parsed as `int`
`ctx.ParamInt64(key string) (int64, error)`	Parsed as `int64`
`ctx.ParamUInt(key string) (uint, error)`	Parsed as `uint`
`ctx.ParamUInt64(key string) (uint64, error)`	Parsed as `uint64`
`ctx.ParamFloat32(key string) (float32, error)`	Parsed as `float32`
`ctx.ParamFloat64(key string) (float64, error)`	Parsed as `float64`
`ctx.Params() map[string]string`	All parameters

app.Get("/users/:id", func(ctx *lightning.Context) {
    id, err := ctx.ParamInt("id")
    if err != nil {
        ctx.JSONError(lightning.StatusBadRequest, "invalid id")
        return
    }
    ctx.JSON(lightning.StatusOK, lightning.Map{"id": id})
})

app.Get("/posts/:slug/edit", func(ctx *lightning.Context) {
    slug := ctx.Param("slug") // e.g. "hello-world"
    ctx.JSON(lightning.StatusOK, lightning.Map{"slug": slug})
})

Wildcard routes

Prefix a path segment with * to match the rest of the URL as a single named value. The wildcard captures everything from that segment to the end of the path, joined with /.

/files/*path   → matches /files/docs/api/v1.html
                 ctx.Param("path") == "docs/api/v1.html"

app.Get("/files/*path", func(ctx *lightning.Context) {
    filePath := ctx.Param("path")
    ctx.JSON(lightning.StatusOK, lightning.Map{"path": filePath})
})

A wildcard segment must be the last segment in a pattern. Putting additional segments after *param has no effect.

Dynamic method registration with `AddRoute`

When you need to register a route for an HTTP method that is determined at runtime, use app.AddRoute directly.

// Signature
func (app *Application) AddRoute(method string, pattern string, handlers []HandlerFunc)

routes := []struct {
    method  string
    pattern string
}{
    {"GET", "/health"},
    {"POST", "/events"},
}

for _, r := range routes {
    r := r // capture loop variable
    app.AddRoute(r.method, r.pattern, []lightning.HandlerFunc{
        func(ctx *lightning.Context) {
            ctx.JSON(lightning.StatusOK, lightning.Map{"method": r.method})
        },
    })
}

AddRoute prepends all global middleware registered with app.Use() before the handlers you supply, matching the behaviour of the typed shorthand methods.

Get Started

Core Concepts

Guides

Configuration

Registering routes

Full example

URL parameters

Reading parameters

Wildcard routes

Dynamic method registration with `AddRoute`

​Registering routes

​Full example

​URL parameters

​Reading parameters

​Wildcard routes

​Dynamic method registration with AddRoute

Registering routes

Full example

URL parameters

Reading parameters

Wildcard routes

Dynamic method registration with `AddRoute`