echo/middleware/request_id.go

package middleware

import (
	"github.com/labstack/echo"
	uuid "github.com/satori/go.uuid"
)

type (
	// RequestIDConfig defines the config for RequestID middleware.
	RequestIDConfig struct {
		// Skipper defines a function to skip middleware.
		Skipper Skipper
	}
)

var (
	// DefaultRequestIDConfig is the default RequestID middleware config.
	DefaultRequestIDConfig = RequestIDConfig{
		Skipper: DefaultSkipper,
	}
)

// RequestID returns a X-Request-ID middleware.
func RequestID() echo.MiddlewareFunc {
	return RequestIDWithConfig(DefaultRequestIDConfig)
}

// RequestIDWithConfig returns a X-Request-ID middleware with config.
func RequestIDWithConfig(config RequestIDConfig) echo.MiddlewareFunc {
	if config.Skipper == nil {
		config.Skipper = DefaultRequestIDConfig.Skipper
	}

	return func(next echo.HandlerFunc) echo.HandlerFunc {
		return func(c echo.Context) error {
			if config.Skipper(c) {
				return next(c)
			}

			req := c.Request()
			res := c.Response()
			rid := req.Header.Get("X-Request-ID")
			if rid == "" {
				rid = uuid.NewV4().String()
			}
			res.Header().Set("X-Request-ID", rid)

			return next(c)
		}
	}
}