Changed Unmarshal to Decode finished logic to populate struct + tests

Author: joeybloggs

context.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/go-playground/form"
 	"github.com/gorilla/websocket"
 	"golang.org/x/net/context"
 )
@@ -57,6 +58,7 @@ type Context interface {
 	TextBytes(int, []byte) error
 	Attachment(r io.Reader, filename string) (err error)
 	Inline(r io.Reader, filename string) (err error)
+	Decode(includeFormQueryParams bool, maxMemory int64, v interface{}) (err error)
 	BaseContext() *Ctx
 }
 
@@ -73,6 +75,7 @@ type Ctx struct {
 	index               int
 	formParsed          bool
 	multipartFormParsed bool
+	l                   *LARS
 }
 
 var _ context.Context = &Ctx{}
@@ -82,6 +85,7 @@ func NewContext(l *LARS) *Ctx {
 
 	c := &Ctx{
 		params: make(Params, l.mostParams),
+		l:      l,
 	}
 
 	c.response = newResponse(nil, c)
@@ -412,6 +416,53 @@ func (c *Ctx) Inline(r io.Reader, filename string) (err error) {
 	return
 }
 
+// Decode takes the request and attempts to discover it's type
+// via http headers and then unmarshal into the provided struct.
+// Example if header was "application/json" would unmarshal using
+// json.NewDecoder(io.LimitReader(c.request.Body, maxMemory)).Decode(v).
+func (c *Ctx) Decode(includeFormQueryParams bool, maxMemory int64, v interface{}) (err error) {
+
+	c.l.formDecoderInit.Do(func() {
+		c.l.formDecoder = form.NewDecoder()
+	})
+
+	typ := c.request.Header.Get(ContentType)
+
+	if idx := strings.Index(typ, ";"); idx != -1 {
+		typ = typ[:idx]
+	}
+
+	switch typ {
+
+	case ApplicationJSON:
+		err = json.NewDecoder(io.LimitReader(c.request.Body, maxMemory)).Decode(v)
+
+	case ApplicationXML:
+		err = xml.NewDecoder(io.LimitReader(c.request.Body, maxMemory)).Decode(v)
+
+	case ApplicationForm:
+
+		if err = c.ParseForm(); err == nil {
+			if includeFormQueryParams {
+				err = c.l.formDecoder.Decode(v, c.request.Form)
+			} else {
+				err = c.l.formDecoder.Decode(v, c.request.PostForm)
+			}
+		}
+
+	case MultipartForm:
+
+		if err = c.ParseMultipartForm(maxMemory); err == nil {
+			if includeFormQueryParams {
+				err = c.l.formDecoder.Decode(v, c.request.Form)
+			} else {
+				err = c.l.formDecoder.Decode(v, c.request.MultipartForm.Value)
+			}
+		}
+	}
+	return
+}
+
 // golang.org/x/net/context functions to comply with context.Context interface and keep context update on lars.Context object
 
 // Context returns the request's context. To change the context, use

context_test.go

@@ -1,12 +1,16 @@
 package lars
 
 import (
+	"bytes"
 	"encoding/xml"
 	"io"
+	"mime/multipart"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"os"
 	"reflect"
+	"strings"
 	"testing"
 	"time"
 
@@ -26,6 +30,124 @@ import (
 // go test -coverprofile cover.out && go tool cover -html=cover.out -o cover.html
 //
 
+func TestDecode(t *testing.T) {
+
+	type TestStruct struct {
+		ID              int `form:"id"`
+		Posted          string
+		MultiPartPosted string
+	}
+
+	test := new(TestStruct)
+
+	l := New()
+	l.Post("/decode/:id", func(c Context) {
+		err := c.Decode(true, 16<<10, test)
+		Equal(t, err, nil)
+	})
+	l.Post("/decode2/:id", func(c Context) {
+		err := c.Decode(false, 16<<10, test)
+		Equal(t, err, nil)
+	})
+	hf := l.Serve()
+
+	form := url.Values{}
+	form.Add("Posted", "value")
+
+	r, _ := http.NewRequest(POST, "/decode/13", strings.NewReader(form.Encode()))
+	r.Header.Set(ContentType, ApplicationForm)
+	w := httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 13)
+	Equal(t, test.Posted, "value")
+	Equal(t, test.MultiPartPosted, "")
+
+	test = new(TestStruct)
+	r, _ = http.NewRequest(POST, "/decode2/13", strings.NewReader(form.Encode()))
+	r.Header.Set(ContentType, ApplicationForm)
+	w = httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 0)
+	Equal(t, test.Posted, "value")
+	Equal(t, test.MultiPartPosted, "")
+
+	body := &bytes.Buffer{}
+	writer := multipart.NewWriter(body)
+
+	err := writer.WriteField("MultiPartPosted", "value")
+	Equal(t, err, nil)
+
+	// Don't forget to close the multipart writer.
+	// If you don't close it, your request will be missing the terminating boundary.
+	err = writer.Close()
+	Equal(t, err, nil)
+
+	test = new(TestStruct)
+	r, _ = http.NewRequest(POST, "/decode/13", body)
+	r.Header.Set(ContentType, writer.FormDataContentType())
+	w = httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 13)
+	Equal(t, test.Posted, "")
+	Equal(t, test.MultiPartPosted, "value")
+
+	body = &bytes.Buffer{}
+	writer = multipart.NewWriter(body)
+
+	err = writer.WriteField("MultiPartPosted", "value")
+	Equal(t, err, nil)
+
+	// Don't forget to close the multipart writer.
+	// If you don't close it, your request will be missing the terminating boundary.
+	err = writer.Close()
+	Equal(t, err, nil)
+
+	test = new(TestStruct)
+	r, _ = http.NewRequest(POST, "/decode2/13", body)
+	r.Header.Set(ContentType, writer.FormDataContentType())
+	w = httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 0)
+	Equal(t, test.Posted, "")
+	Equal(t, test.MultiPartPosted, "value")
+
+	jsonBody := `{"ID":13,"Posted":"value","MultiPartPosted":"value"}`
+	test = new(TestStruct)
+	r, _ = http.NewRequest(POST, "/decode/13", strings.NewReader(jsonBody))
+	r.Header.Set(ContentType, ApplicationJSON)
+	w = httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 13)
+	Equal(t, test.Posted, "value")
+	Equal(t, test.MultiPartPosted, "value")
+
+	xmlBody := `<TestStruct><ID>13</ID><Posted>value</Posted><MultiPartPosted>value</MultiPartPosted></TestStruct>`
+	test = new(TestStruct)
+	r, _ = http.NewRequest(POST, "/decode/13", strings.NewReader(xmlBody))
+	r.Header.Set(ContentType, ApplicationXML)
+	w = httptest.NewRecorder()
+
+	hf.ServeHTTP(w, r)
+
+	Equal(t, w.Code, http.StatusOK)
+	Equal(t, test.ID, 13)
+	Equal(t, test.Posted, "value")
+	Equal(t, test.MultiPartPosted, "value")
+}
+
 func TestStream(t *testing.T) {
 	l := New()
 

lars.go

@@ -6,6 +6,8 @@ import (
 	"reflect"
 	"strings"
 	"sync"
+
+	"github.com/go-playground/form"
 )
 
 // HTTP Constant Terms and Variables
@@ -150,6 +152,10 @@ type LARS struct {
 	// if enabled automatically handles OPTION requests; manually configured OPTION
 	// handlers take precidence. default true
 	automaticallyHandleOPTIONS bool
+
+	// form decoder + once initialization
+	formDecoder     *form.Decoder
+	formDecoderInit sync.Once
 }
 
 // RouteMap contains a single routes full path