fiber/docs/middleware/cache.md

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Cache

Cache middleware for Fiber designed to intercept responses and cache them. This middleware caches the Body, Content-Type, and StatusCode using a key built from the request path and method. Special thanks to @codemicro for creating this middleware for Fiber core!

Request Directives
Cache-Control: no-cache will return the up-to-date response but still caches it. You will always get a miss cache status.
Cache-Control: no-store will refrain from caching. You will always get the up-to-date response.

If the server response contains a Cache-Control: max-age directive, its value is used as the expiration time for the cache entry.

Cacheable Status Codes

This middleware caches responses with the following status codes according to RFC7231:

• 200: OK
• 203: Non-Authoritative Information
• 204: No Content
• 206: Partial Content
• 300: Multiple Choices
• 301: Moved Permanently
• 404: Not Found
• 405: Method Not Allowed
• 410: Gone
• 414: URI Too Long
• 501: Not Implemented

If the status code is other than these, you will always get an unreachable cache status.

For more information about cacheable status codes or RFC7231, please refer to the following resources:

• Cacheable - MDN Web Docs

• RFC7231 - Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Signatures

func New(config ...Config) fiber.Handler

Examples

Import the middleware package that is part of the Fiber web framework

import (
    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/cache"
)

After you initiate your Fiber app, you can use the following possibilities:

// Initialize default config
app.Use(cache.New())

// Or extend your config for customization
app.Use(cache.New(cache.Config{
    Next: func(c fiber.Ctx) bool {
        return fiber.Query[bool](c, "noCache")
    },
    Expiration: 30 * time.Minute,
    CacheControl: true,
}))

Or you can customize the key and expiration time like this (the HTTP method is automatically appended to the key):

app.Use(cache.New(cache.Config{
    ExpirationGenerator: func(c fiber.Ctx, cfg *cache.Config) time.Duration {
        newCacheTime, _ := strconv.Atoi(c.GetRespHeader("Cache-Time", "600"))
        return time.Second * time.Duration(newCacheTime)
    },
    KeyGenerator: func(c fiber.Ctx) string {
        return utils.CopyString(c.Path())
    },
}))

app.Get("/", func(c fiber.Ctx) error {
    c.Response().Header.Add("Cache-Time", "6000")
    return c.SendString("hi")
})

You can also invalidate the cache by using the CacheInvalidator function as shown below:

app.Use(cache.New(cache.Config{
    CacheInvalidator: func(c fiber.Ctx) bool {
        return fiber.Query[bool](c, "invalidateCache")
    },
}))

The CacheInvalidator function allows you to define custom conditions for cache invalidation. Return true if conditions such as specific query parameters or headers are met, which require the cache to be invalidated. For example, in this code, the cache is invalidated when the query parameter invalidateCache is set to true.

Config

Property	Type	Description	Default
Next	func(fiber.Ctx) bool	Next defines a function that is executed before creating the cache entry and can be used to execute the request without cache creation. If an entry already exists, it will be used. If you want to completely bypass the cache functionality in certain cases, you should use the skip middleware.	nil
Expiration	time.Duration	Expiration is the time that a cached response will live.	1 * time.Minute
CacheHeader	string	CacheHeader is the header on the response header that indicates the cache status, with the possible return values "hit," "miss," or "unreachable."	X-Cache
CacheControl	bool	CacheControl enables client-side caching if set to true.	false
CacheInvalidator	func(fiber.Ctx) bool	CacheInvalidator defines a function that is executed before checking the cache entry. It can be used to invalidate the existing cache manually by returning true.	nil
KeyGenerator	func(fiber.Ctx) string	Key allows you to generate custom keys. The HTTP method is appended automatically.	func(c fiber.Ctx) string { return utils.CopyString(c.Path()) }
ExpirationGenerator	func(fiber.Ctx, *cache.Config) time.Duration	ExpirationGenerator allows you to generate custom expiration keys based on the request.	nil
Storage	fiber.Storage	Storage is used to store the state of the middleware.	In-memory store
StoreResponseHeaders	bool	StoreResponseHeaders allows you to store additional headers generated by next middlewares & handler.	false
MaxBytes	uint	MaxBytes is the maximum number of bytes of response bodies simultaneously stored in cache.	0 (No limit)
Methods	[]string	Methods specifies the HTTP methods to cache.	[]string{fiber.MethodGet, fiber.MethodHead}

Default Config

var ConfigDefault = Config{
    Next:         nil,
    Expiration:   1 * time.Minute,
    CacheHeader:  "X-Cache",
    CacheControl: false,
    CacheInvalidator: nil,
    KeyGenerator: func(c fiber.Ctx) string {
        return utils.CopyString(c.Path())
    },
    ExpirationGenerator:  nil,
    StoreResponseHeaders: false,
    Storage:              nil,
    MaxBytes:             0,
    Methods: []string{fiber.MethodGet, fiber.MethodHead},
}