🧰 Utils

Generics

Convert

Converts a string to a specific type while handling errors and optional defaults. It wraps conversion and fallback logic to keep your code clean and consistent.

Signature

func Convert[T any](value string, converter func(string) (T, error), defaultValue ...T) (T, error)

Example

// GET http://example.com/id/bb70ab33-d455-4a03-8d78-d3c1dacae9ff
app.Get("/id/:id", func(c fiber.Ctx) error {
    fiber.Convert(c.Params("id"), uuid.Parse)                   // UUID(bb70ab33-d455-4a03-8d78-d3c1dacae9ff), nil
})

// GET http://example.com/search?id=65f6f54221fb90e6a6b76db7
app.Get("/search", func(c fiber.Ctx) error {
    fiber.Convert(c.Query("id"), mongo.ParseObjectID)           // objectid(65f6f54221fb90e6a6b76db7), nil
    fiber.Convert(c.Query("id"), uuid.Parse)                    // uuid.Nil, error(cannot parse given uuid)
    fiber.Convert(c.Query("id"), uuid.Parse, mongo.NewObjectID) // new object id generated and return nil as error.
    return nil
})

// ...

GetReqHeader

Retrieves an HTTP request header as a specific type using generics.

Signature

func GetReqHeader[V GenericType](c Ctx, key string, defaultValue ...V) V

Example

app.Get("/search", func(c fiber.Ctx) error {
    // curl -X GET http://example.com/search -H "X-Request-ID: 12345" -H "X-Request-Name: John"
    fiber.GetReqHeader[int](c, "X-Request-ID")               // => returns 12345 as integer.
    fiber.GetReqHeader[string](c, "X-Request-Name")          // => returns "John" as string.
    fiber.GetReqHeader[string](c, "unknownParam", "default") // => returns "default" as string.
    // ...
})

Locals

Reads or writes local values in the request context using generics.

Signature

// Set a value
func Locals[V any](c Ctx, key any, value ...V) V
// Get a value
func Locals[V any](c Ctx, key any) V

Example

app.Use("/user/:user/:id", func(c fiber.Ctx) error {
    // set local values
    fiber.Locals[string](c, "user", "john")
    fiber.Locals[int](c, "id", 25)
    // ...
    
    return c.Next()
})


app.Get("/user/*", func(c fiber.Ctx) error {
    // get local values
    name := fiber.Locals[string](c, "user") // john
    age := fiber.Locals[int](c, "id")       // 25
    // ...
})

Params

Retrieves route parameters as a specific type.

Signature

func Params[V GenericType](c Ctx, key string, defaultValue ...V) V

Example

app.Get("/user/:user/:id", func(c fiber.Ctx) error {
    // http://example.com/user/john/25
    fiber.Params[int](c, "id")               // => returns 25 as integer.
    fiber.Params[int](c, "unknownParam", 99) // => returns the default 99 as integer.
    // ...
    return c.SendString("Hello, " + fiber.Params[string](c, "user"))
})

Query

Retrieves query parameters as a specific type.

Signature

func Query[V GenericType](c Ctx, key string, defaultValue ...V) V

Example

app.Get("/search", func(c fiber.Ctx) error {
    // http://example.com/search?name=john&age=25
    fiber.Query[string](c, "name")                    // => returns "john"
    fiber.Query[int](c, "age")                        // => returns 25 as integer.
    fiber.Query[string](c, "unknownParam", "default") // => returns "default" as string.
    // ...
})

RoutePatternMatch

Checks whether a given path matches a Fiber route pattern. Useful for testing patterns without registering them. Patterns may contain parameters, wildcards and optional segments. An optional Config allows control over case sensitivity and strict routing.

The path is normalized the way the router normalizes a request path before matching, so the answer agrees with what the app would actually do. In particular, with the default StrictRouting: false a trailing slash on the path is ignored, so RoutePatternMatch("/a/", "/a") reports true. Set StrictRouting: true if you need the two forms to be distinguished.

It takes a path, not a request target. The empty string is read as /, and any other string without a leading slash matches no pattern, so RoutePatternMatch("*", "/*") reports false. The router instead roots a request target that has no leading slash before matching, so it routes OPTIONS * as /*.

Signature

func RoutePatternMatch(path, pattern string, cfg ...Config) bool

Example

fiber.RoutePatternMatch("/user/john", "/user/:name") // true

fiber.RoutePatternMatch(
    "/User/john",
    "/user/:name",
    fiber.Config{CaseSensitive: true},
) // false