Documentation
¶
Overview ¶
Package middleware provides a standard approach for chaining and composing HTTP middleware.
Usage ¶
The core type is Pipe, an adapter that wraps an http.Handler to add functionality. The Chain function composes these pipes into a single handler. The package also includes common middleware like Recover for panic handling, RequestID for tracing, and Log for request logging.
Example:
handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("OK"))
})
// Chain middleware around the final handler.
// Order matters: Recover must be first (outermost).
logger := slog.Default()
chainedHandler := middleware.Chain(handler,
middleware.Recover(logger),
middleware.RequestID(),
middleware.Log(logger),
)
http.ListenAndServe(":8080", chainedHandler)
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Chain ¶
Chain combines a handler with multiple middleware Pipes. The pipes are applied in reverse order, meaning the first pipe in the list is the outermost and executes first.
For example, Chain(h, A, B, C) results in a handler equivalent to A(B(C(h))). Any nil pipes in the list are safely ignored.
func GetRequestID ¶
GetRequestID retrieves the request ID from a given context. It returns an empty string if the ID is not found.
Types ¶
type Pipe ¶
Pipe is a middleware function. It's an adapter that takes an http.Handler and returns a new http.Handler, allowing functionality to be composed in layers.
func Log ¶
Log returns a middleware Pipe that logs a summary of each HTTP request. It captures the final HTTP status code by wrapping the http.ResponseWriter.
The log entry is generated at the debug level after the request has been handled. It includes the method, URL, status code, duration, and other common attributes. To include a request ID in the log, this middleware should be placed after the RequestID middleware in the chain.
func Recover ¶
Recover produces a middleware Pipe that catches panics in downstream handlers. It uses the provided logger to report the exception with a stack trace and returns an empty response with status code 500 to the client. The log entry also pinpoints the request method and URL that caused the panic. For maximum effectiveness, this should be the first (outermost) middleware in the chain.
func RequestID ¶
func RequestID() Pipe
RequestID returns a middleware Pipe that injects a unique ID into each request. It adds the ID to the response via the "X-Request-ID" header and to the request's context for downstream use.
Downstream handlers and other middleware can retrieve the ID using GetRequestID. If a unique ID cannot be generated from the random source, this middleware does nothing and passes the request to the next handler.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
Package cors provides a configurable CORS (Cross-Origin Resource Sharing) middleware for http.Handlers.
|
Package cors provides a configurable CORS (Cross-Origin Resource Sharing) middleware for http.Handlers. |
|
Package gzip provides an HTTP middleware for compressing response bodies using the gzip algorithm.
|
Package gzip provides an HTTP middleware for compressing response bodies using the gzip algorithm. |