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Version: v3.x

🧰 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 exactly the way the router normalizes an incoming request 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.

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
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