goa

Documentation

Overview

Package goa contains middleware for monitoring Goa applications.

The provided middleware works in the same way as compass/http.

Example usage:

// Get hooks and resolver for the middleware.
hooks := prom.NewHooks(nil)
resolver := NewContextResolver()

// Create the middleware.
mw, err := NewMiddleware(hooks, resolver)
if err != nil {
	panic(err)
}

// Use the middleware in a service.
svc := goa.New("example")
svc.Use(mw)
svc.ListenAndServe(":8080")

Index

• func MustNewMiddleware(hooks mhttp.Hooks, resolver mhttp.Resolver) goa.Middleware
• func NewMiddleware(hooks mhttp.Hooks, resolver mhttp.Resolver) (goa.Middleware, error)

Examples

• MustNewMiddleware

Functions

func MustNewMiddleware

func MustNewMiddleware(hooks mhttp.Hooks, resolver mhttp.Resolver) goa.Middleware

MustNewMiddleware is like NewMiddleware, except it panics where NewMiddleware would return an error.

Example

package main

import (
	"net/http"

	"github.com/goadesign/goa"
	mgoa "github.com/zenreach/compass/goa"
	mhttp "github.com/zenreach/compass/http"
)

func main() {
	// To keep this simply our hooks won't do anything.
	hooks := &NilHooks{}

	// Create a resolver to name our endpoint "hello".
	resolver := mhttp.ResolverFunc(func(*http.Request) string {
		return "hello"
	})

	// Create the Goa service, assign our middleware, and run it.
	svc := goa.New("example")
	svc.Use(mgoa.MustNewMiddleware(hooks, resolver))
	svc.ListenAndServe(":8080")
}

// NilHooks implements http.Hooks as a set of noops.
type NilHooks struct{}

func (*NilHooks) RequestHook(endpoint string, req *http.Request) {}

func (*NilHooks) ResponseHook(endpoint string, req *http.Request, res *mhttp.Response) {}

func NewMiddleware

func NewMiddleware(hooks mhttp.Hooks, resolver mhttp.Resolver) (goa.Middleware, error)

NewMiddleware creates a Goa middleware which calls the provided hooks during the request cycle. This must be used as the net/http middleware produced by http.NewMiddleware is incompatible with Goa.