commands: Added Length field to Response

squash! commands: Added Length field to Response

commands/http: client: Fixed error on unset length

http/client.go

@@ -8,6 +8,7 @@ import (
 	"net/http"
 	"net/url"
 	"reflect"
+	"strconv"
 	"strings"
 
 	cmds "github.com/jbenet/go-ipfs/commands"
@@ -137,9 +138,18 @@ func getResponse(httpRes *http.Response, req cmds.Request) (cmds.Response, error
 	var err error
 	res := cmds.NewResponse(req)
 
-	contentType := httpRes.Header["Content-Type"][0]
+	contentType := httpRes.Header.Get(contentTypeHeader)
 	contentType = strings.Split(contentType, ";")[0]
 
+	lengthHeader := httpRes.Header.Get(contentLengthHeader)
+	if len(lengthHeader) > 0 {
+		length, err := strconv.ParseUint(lengthHeader, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+		res.SetLength(length)
+	}
+
 	if len(httpRes.Header.Get(streamHeader)) > 0 {
 		// if output is a stream, we can just use the body reader
 		res.SetOutput(httpRes.Body)

http/handler.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"strconv"
 
 	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
 
@@ -92,6 +93,11 @@ func (i Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set(contentTypeHeader, mime)
 	}
 
+	// set the Content-Length from the response length
+	if res.Length() > 0 {
+		w.Header().Set(contentLengthHeader, strconv.FormatUint(res.Length(), 10))
+	}
+
 	// if response contains an error, write an HTTP error status code
 	if e := res.Error(); e != nil {
 		if e.Code == cmds.ErrClient {

response.go

@@ -95,6 +95,10 @@ type Response interface {
 	SetOutput(interface{})
 	Output() interface{}
 
+	// Sets/Returns the length of the output
+	SetLength(uint64)
+	Length() uint64
+
 	// Marshal marshals out the response into a buffer. It uses the EncodingType
 	// on the Request to chose a Marshaler (Codec).
 	Marshal() (io.Reader, error)
@@ -108,6 +112,7 @@ type response struct {
 	err    *Error
 	value  interface{}
 	out    io.Reader
+	length uint64
 }
 
 func (r *response) Request() Request {
@@ -122,6 +127,14 @@ func (r *response) SetOutput(v interface{}) {
 	r.value = v
 }
 
+func (r *response) Length() uint64 {
+	return r.length
+}
+
+func (r *response) SetLength(l uint64) {
+	r.length = l
+}
+
 func (r *response) Error() *Error {
 	return r.err
 }