requestid.go

package middleware

import (
	"context"
	"net/http"

	"goa.design/goa/v3/middleware"
)

// RequestID returns a middleware, which initializes the context with a unique
// value under the RequestIDKey key. Optionally uses the incoming "X-Request-Id"
// header, if present, with or without a length limit to use as request ID. the
// default behavior is to always generate a new ID.
//
// examples of use:
//
//	service.Use(middleware.RequestID())
//
//	// enable options for using "X-Request-Id" header with length limit.
//	service.Use(middleware.RequestID(
//	  middleware.UseXRequestIDHeaderOption(true),
//	  middleware.XRequestHeaderLimitOption(128)))
//
//	// enable options for using "Custom-Id" header.
//	service.Use(middleware.RequestID(middleware.RequestIDHeaderOption("Custom-Id"))
//
// Deprecated: use OpenTelemetry instead, see for example
// github.com/goadesign/clue. This function will be removed in a future version
// of Goa.
func RequestID(options ...middleware.RequestIDOption) func(http.Handler) http.Handler {
	o := middleware.NewRequestIDOptions(options...)
	useReqID := o.IsUseRequestID()
	reqIDHeader := o.RequestIDHeader()
	return func(h http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			ctx := r.Context()
			if useReqID {
				if id := r.Header.Get(reqIDHeader); id != "" {
					ctx = context.WithValue(ctx, middleware.RequestIDKey, id) // nolint: staticcheck
				}
			}
			ctx = middleware.GenerateRequestID(ctx, o)
			h.ServeHTTP(w, r.WithContext(ctx))
		})
	}
}

// UseXRequestIDHeaderOption enables/disables using "X-Request-Id" header.
func UseXRequestIDHeaderOption(f bool) middleware.RequestIDOption {
	return middleware.UseRequestIDOption(f)
}

// RequestIDHeaderOption sets the name of the header used to capture the incoming
// request ID. This option also automatically enabled the use of that header.
func RequestIDHeaderOption(name string) middleware.RequestIDOption {
	return middleware.RequestIDHeaderOption(name)
}

// XRequestHeaderLimitOption sets the option for using "X-Request-Id" header.
func XRequestHeaderLimitOption(limit int) middleware.RequestIDOption {
	return middleware.RequestIDLimitOption(limit)
}