Support gzip encoding

pkg/schemaserver/server/server.go

@@ -41,21 +41,27 @@ func DefaultAPIServer() *Server {
 	s := &Server{
 		Schemas: types.EmptyAPISchemas().MustAddSchemas(builtin.Schemas),
 		ResponseWriters: map[string]types.ResponseWriter{
-			"json": &writer.EncodingResponseWriter{
+			"json": &writer.GzipWriter{
+				ResponseWriter: &writer.EncodingResponseWriter{
 					ContentType: "application/json",
 					Encoder:     types.JSONEncoder,
 				},
-			"html": &writer.HTMLResponseWriter{
+			},
+			"html": &writer.GzipWriter{
+				ResponseWriter: &writer.HTMLResponseWriter{
 					EncodingResponseWriter: writer.EncodingResponseWriter{
 						Encoder:     types.JSONEncoder,
 						ContentType: "application/json",
 					},
 				},
-			"yaml": &writer.EncodingResponseWriter{
+			},
+			"yaml": &writer.GzipWriter{
+				ResponseWriter: &writer.EncodingResponseWriter{
 					ContentType: "application/yaml",
 					Encoder:     types.YAMLEncoder,
 				},
 			},
+		},
 		AccessControl: &SchemaBasedAccess{},
 		Defaults: Defaults{
 			ByIDHandler:   handlers.ByIDHandler,

pkg/schemaserver/writer/gzip.go

@@ -0,0 +1,52 @@
+package writer
+
+import (
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"strings"
+
+	"github.com/rancher/steve/pkg/schemaserver/types"
+)
+
+type GzipWriter struct {
+	types.ResponseWriter
+}
+
+func setup(apiOp *types.APIRequest) (*types.APIRequest, io.Closer) {
+	if !strings.Contains(apiOp.Request.Header.Get("Accept-Encoding"), "gzip") {
+		return apiOp, ioutil.NopCloser(nil)
+	}
+
+	apiOp.Response.Header().Set("Content-Encoding", "gzip")
+	apiOp.Response.Header().Del("Content-Length")
+
+	gz := gzip.NewWriter(apiOp.Response)
+	gzw := &gzipResponseWriter{Writer: gz, ResponseWriter: apiOp.Response}
+
+	newOp := *apiOp
+	newOp.Response = gzw
+	return &newOp, gz
+}
+
+func (g *GzipWriter) Write(apiOp *types.APIRequest, code int, obj types.APIObject) {
+	apiOp, closer := setup(apiOp)
+	defer closer.Close()
+	g.ResponseWriter.Write(apiOp, code, obj)
+}
+
+func (g *GzipWriter) WriteList(apiOp *types.APIRequest, code int, obj types.APIObjectList) {
+	apiOp, closer := setup(apiOp)
+	defer closer.Close()
+	g.ResponseWriter.WriteList(apiOp, code, obj)
+}
+
+type gzipResponseWriter struct {
+	io.Writer
+	http.ResponseWriter
+}
+
+func (g gzipResponseWriter) Write(b []byte) (int, error) {
+	return g.Writer.Write(b)
+}