Compress HTTP API responses

api/api.go

@@ -2,6 +2,7 @@ package api
 
 import (
 	"bytes"
+	"compress/gzip"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -194,6 +195,7 @@ func (r *request) toHTTP() (*http.Request, error) {
 		return nil, err
 	}
 
+	req.Header.Add("Accept-Encoding", "gzip")
 	req.URL.Host = r.url.Host
 	req.URL.Scheme = r.url.Scheme
 	req.Host = r.url.Host
@@ -231,6 +233,26 @@ func (c *Client) newRequest(method, path string) *request {
 	return r
 }
 
+// multiCloser is to wrap a ReadCloser such that when close is called, multiple
+// Closes occur.
+type multiCloser struct {
+	reader       io.Reader
+	inorderClose []io.Closer
+}
+
+func (m *multiCloser) Close() error {
+	for _, c := range m.inorderClose {
+		if err := c.Close(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (m *multiCloser) Read(p []byte) (int, error) {
+	return m.reader.Read(p)
+}
+
 // doRequest runs a request with our client
 func (c *Client) doRequest(r *request) (time.Duration, *http.Response, error) {
 	req, err := r.toHTTP()
@@ -240,6 +262,29 @@ func (c *Client) doRequest(r *request) (time.Duration, *http.Response, error) {
 	start := time.Now()
 	resp, err := c.config.HttpClient.Do(req)
 	diff := time.Now().Sub(start)
+
+	// If the response is compressed, we swap the body's reader.
+	if resp != nil && resp.Header != nil {
+		var reader io.ReadCloser
+		switch resp.Header.Get("Content-Encoding") {
+		case "gzip":
+			greader, err := gzip.NewReader(resp.Body)
+			if err != nil {
+				return 0, nil, err
+			}
+
+			// The gzip reader doesn't close the wrapped reader so we use
+			// multiCloser.
+			reader = &multiCloser{
+				reader:       greader,
+				inorderClose: []io.Closer{greader, resp.Body},
+			}
+		default:
+			reader = resp.Body
+		}
+		resp.Body = reader
+	}
+
 	return diff, resp, err
 }
 

command/agent/http.go

@@ -12,6 +12,7 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/NYTimes/gziphandler"
 	"github.com/hashicorp/nomad/nomad/structs"
 	"github.com/ugorji/go/codec"
 )
@@ -65,7 +66,7 @@ func NewHTTPServer(agent *Agent, config *Config, logOutput io.Writer) (*HTTPServ
 	srv.registerHandlers(config.EnableDebug)
 
 	// Start the server
-	go http.Serve(ln, mux)
+	go http.Serve(ln, gziphandler.GzipHandler(mux))
 	return srv, nil
 }
 
@@ -86,7 +87,7 @@ func newScadaHttp(agent *Agent, list net.Listener) *HTTPServer {
 	srv.registerHandlers(false) // Never allow debug for SCADA
 
 	// Start the server
-	go http.Serve(list, mux)
+	go http.Serve(list, gziphandler.GzipHandler(mux))
 	return srv
 }
 

vendor/vendor.json

@@ -2,6 +2,12 @@
 	"comment": "",
 	"ignore": "test",
 	"package": [
+		{
+			"checksumSHA1": "XeG94RjA9o/0wo9Fuw6NSRGYnjk=",
+			"path": "github.com/NYTimes/gziphandler",
+			"revision": "63027b26b87e2ae2ce3810393d4b81021cfd3a35",
+			"revisionTime": "2016-04-19T20:25:41Z"
+		},
 		{
 			"comment": "v0.8.7-87-g4b6ea73",
 			"path": "github.com/Sirupsen/logrus",

website/source/docs/http/index.html.md

@@ -87,6 +87,11 @@ servicing the request. A target region can be explicitly specified with the `reg
 parameter. The request will be transparently forwarded and serviced by a server in the
 appropriate region.
 
+## Compressed Responses
+
+The HTTP API will gzip the response if the HTTP request denotes that the client accepts
+gzip compression. This is achieved via the standard, `Accept-Encoding: gzip`
+
 ## Formatted JSON Output
 
 By default, the output of all HTTP API requests is minimized JSON.  If the client passes `pretty`