nap

#Nap#

Simple, and I mean simple, REST framework for JSON-based responses.

##Usage##

###Simple###

Here is a dead-simple REST API.

package main

import (
	"net/http"

	"github.com/crawford/nap"
)

func Hello(req *http.Request) (interface{}, nap.Status) {
	return "Hello, World!", nap.OK{}
}

func main() {
	http.Handle("/hello", nap.HandlerFunc(Hello))
	http.Handle("/", nap.NotFoundHandler)
	http.ListenAndServe(":8080", nil)
}

And here it is in action!

curl localhost:8080/hello

{
	"Hello, World!"
}

curl localhost:8080/bye

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###Custom Wrapper###

It's also possible to customize the response from Nap.

package main

import (
	"net/http"

	"github.com/crawford/nap"
)

type payloadWrapper struct{}

func (w payloadWrapper) Wrap(payload interface{}, status nap.Status) (interface{}, int) {
	return map[string]interface{}{
		"status": map[string]interface{}{
			"code":    status.Code(),
			"message": status.Message(),
		},
		"result": payload,
	}, status.Code()
}

func Hello(req *http.Request) (interface{}, nap.Status) {
	return "Hello, World!", nap.OK{}
}

func main() {
	http.Handle("/hello", nap.HandlerFunc(Hello))
	http.Handle("/", nap.NotFoundHandler)
	http.ListenAndServe(":8080", nil)
}

And here it is in action!

curl localhost:8080/hello

{
	"result": "Hello, World!",
	"status": {
		"code": 200,
		"message": ""
	}
}

curl localhost:8080/bye

{
	"result": null,
	"status": {
		"code": 404,
		"message": "resource not found"
	}
}

###Extra Parameters###

Here is a more interesting example. This pattern is useful for injecting extra parameters into your handlers.

package main

import (
	"net/http"
	"net/url"
	"time"

	"github.com/crawford/nap"
)

func Info(now time.Time, req *http.Request) (interface{}, nap.Status) {
	return struct {
		Url  *url.URL
		Host string
		Time time.Time
	}{
		Url:  req.URL,
		Host: req.Host,
		Time: now,
	}, nap.OK{}
}

func AddTimestamp(fn func(time.Time, *http.Request) (interface{}, nap.Status)) http.Handler {
	return nap.HandlerFunc(func(req *http.Request) (interface{}, nap.Status) {
		return fn(time.Now(), req)
	})
}

func main() {
	http.Handle("/info", AddTimestamp(Info))
	http.Handle("/", nap.NotFoundHandler)
	http.ListenAndServe(":8080", nil)
}

And the result!

{
	"Url": {
		"Scheme": "",
		"Opaque": "",
		"User": null,
		"Host": "",
		"Path": "/info",
		"RawQuery": "",
		"Fragment": ""
	},
	"Host": "localhost:8080",
	"Time": "2014-06-21T23:26:09.002024789-07:00"
}

###Panic###

Not a very good programmer?

package main

import (
	"net/http"

	"github.com/crawford/nap"
)

func Panic(req *http.Request) (interface{}, nap.Status) {
	panic("AHH")
}

func main() {
	http.Handle("/panic", nap.HandlerFunc(Panic))
	http.Handle("/", nap.NotFoundHandler)
	http.ListenAndServe(":8080", nil)
}

Nice save!

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