Add XML rendering

README.md

@@ -1,5 +1,5 @@
 # render [![wercker status](https://app.wercker.com/status/fcf6b26a1b41f53540200b1949b48dec "wercker status")](https://app.wercker.com/project/bykey/fcf6b26a1b41f53540200b1949b48dec)
-Martini middleware/handler for easily rendering serialized JSON and HTML template responses.
+Martini middleware/handler for easily rendering serialized JSON, XML, and HTML template responses.
 
 [API Reference](http://godoc.org/github.com/martini-contrib/render)
 
@@ -47,6 +47,7 @@ m.Use(render.Renderer(render.Options{
   Delims: render.Delims{"{[{", "}]}"}, // Sets delimiters to the specified strings.
   Charset: "UTF-8", // Sets encoding for json and html content-types. Default is "UTF-8".
   IndentJSON: true, // Output human readable JSON
+  IndentXML: true, // Output human readable XML
   HTMLContentType: "application/xhtml+xml", // Output XHTML content type instead of default "text/html"
 }))
 // ...

render.go

@@ -26,6 +26,7 @@ package render
 import (
 	"bytes"
 	"encoding/json"
+	"encoding/xml"
 	"fmt"
 	"html/template"
 	"io"
@@ -41,10 +42,11 @@ import (
 const (
 	ContentType    = "Content-Type"
 	ContentLength  = "Content-Length"
+	ContentBinary  = "application/octet-stream"
 	ContentJSON    = "application/json"
 	ContentHTML    = "text/html"
 	ContentXHTML   = "application/xhtml+xml"
-	ContentBinary  = "application/octet-stream"
+	ContentXML     = "text/xml"
 	defaultCharset = "UTF-8"
 )
 
@@ -65,6 +67,8 @@ type Render interface {
 	JSON(status int, v interface{})
 	// HTML renders a html template specified by the name and writes the result and given status to the http.ResponseWriter.
 	HTML(status int, name string, v interface{}, htmlOpt ...HTMLOptions)
+	// XML writes the given status and XML serialized version of the given value to the http.ResponseWriter.
+	XML(status int, v interface{})
 	// Data writes the raw byte array to the http.ResponseWriter.
 	Data(status int, v []byte)
 	// Error is a convenience function that writes an http status to the http.ResponseWriter.
@@ -103,8 +107,12 @@ type Options struct {
 	Charset string
 	// Outputs human readable JSON
 	IndentJSON bool
+	// Outputs human readable XML
+	IndentXML bool
 	// Prefixes the JSON output with the given bytes.
 	PrefixJSON []byte
+	// Prefixes the XML output with the given bytes.
+	PrefixXML []byte
 	// Allows changing of output to XHTML instead of HTML. Default is "text/html"
 	HTMLContentType string
 }
@@ -266,6 +274,28 @@ func (r *renderer) HTML(status int, name string, binding interface{}, htmlOpt ..
 	io.Copy(r, out)
 }
 
+func (r *renderer) XML(status int, v interface{}) {
+	var result []byte
+	var err error
+	if r.opt.IndentXML {
+		result, err = xml.MarshalIndent(v, "", "  ")
+	} else {
+		result, err = xml.Marshal(v)
+	}
+	if err != nil {
+		http.Error(r, err.Error(), 500)
+		return
+	}
+
+	// json rendered fine, write out the result
+	r.Header().Set(ContentType, ContentXML+r.compiledCharset)
+	r.WriteHeader(status)
+	if len(r.opt.PrefixXML) > 0 {
+		r.Write(r.opt.PrefixXML)
+	}
+	r.Write(result)
+}
+
 func (r *renderer) Data(status int, v []byte) {
 	if r.Header().Get(ContentType) == "" {
 		r.Header().Set(ContentType, ContentBinary)

render_test.go

@@ -1,6 +1,7 @@
 package render
 
 import (
+	"encoding/xml"
 	"html/template"
 	"net/http"
 	"net/http/httptest"
@@ -16,6 +17,12 @@ type Greeting struct {
 	Two string `json:"two"`
 }
 
+type GreetingXML struct {
+	XMLName xml.Name `xml:"greeting"`
+	One     string   `xml:"one,attr"`
+	Two     string   `xml:"two,attr"`
+}
+
 func Test_Render_JSON(t *testing.T) {
 	m := martini.Classic()
 	m.Use(Renderer(Options{
@@ -56,7 +63,7 @@ func Test_Render_JSON_Prefix(t *testing.T) {
 
 	expect(t, res.Code, 300)
 	expect(t, res.Header().Get(ContentType), ContentJSON+"; charset=UTF-8")
-	expect(t, res.Body.String(), prefix + `{"one":"hello","two":"world"}`)
+	expect(t, res.Body.String(), prefix+`{"one":"hello","two":"world"}`)
 }
 
 func Test_Render_Indented_JSON(t *testing.T) {
@@ -83,6 +90,70 @@ func Test_Render_Indented_JSON(t *testing.T) {
 }`)
 }
 
+func Test_Render_XML(t *testing.T) {
+	m := martini.Classic()
+	m.Use(Renderer(Options{
+	// nothing here to configure
+	}))
+
+	// routing
+	m.Get("/foobar", func(r Render) {
+		r.XML(300, GreetingXML{One: "hello", Two: "world"})
+	})
+
+	res := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/foobar", nil)
+
+	m.ServeHTTP(res, req)
+
+	expect(t, res.Code, 300)
+	expect(t, res.Header().Get(ContentType), ContentXML+"; charset=UTF-8")
+	expect(t, res.Body.String(), `<greeting one="hello" two="world"></greeting>`)
+}
+
+func Test_Render_XML_Prefix(t *testing.T) {
+	m := martini.Classic()
+	prefix := ")]}',\n"
+	m.Use(Renderer(Options{
+		PrefixXML: []byte(prefix),
+	}))
+
+	// routing
+	m.Get("/foobar", func(r Render) {
+		r.XML(300, GreetingXML{One: "hello", Two: "world"})
+	})
+
+	res := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/foobar", nil)
+
+	m.ServeHTTP(res, req)
+
+	expect(t, res.Code, 300)
+	expect(t, res.Header().Get(ContentType), ContentXML+"; charset=UTF-8")
+	expect(t, res.Body.String(), prefix+`<greeting one="hello" two="world"></greeting>`)
+}
+
+func Test_Render_Indented_XML(t *testing.T) {
+	m := martini.Classic()
+	m.Use(Renderer(Options{
+		IndentXML: true,
+	}))
+
+	// routing
+	m.Get("/foobar", func(r Render) {
+		r.XML(300, GreetingXML{One: "hello", Two: "world"})
+	})
+
+	res := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/foobar", nil)
+
+	m.ServeHTTP(res, req)
+
+	expect(t, res.Code, 300)
+	expect(t, res.Header().Get(ContentType), ContentXML+"; charset=UTF-8")
+	expect(t, res.Body.String(), `<greeting one="hello" two="world"></greeting>`)
+}
+
 func Test_Render_Bad_HTML(t *testing.T) {
 	m := martini.Classic()
 	m.Use(Renderer(Options{