feat: add gzip to http responses for query/batch-query

pkg/api/handler_utils.go

@@ -0,0 +1,37 @@
+package api
+
+import (
+	"compress/gzip"
+	"io"
+	"net/http"
+	"strings"
+)
+
+type gzipResponseWriter struct {
+	io.Writer
+	http.ResponseWriter
+}
+
+func (w gzipResponseWriter) Write(b []byte) (int, error) {
+	return w.Writer.Write(b)
+}
+
+func gzipWrapper(handler http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Check that path ends in /query or /batch-query
+		if !strings.HasSuffix(r.URL.Path, "/query") && !strings.HasSuffix(r.URL.Path, "/batch-query") {
+			handler.ServeHTTP(w, r)
+			return
+		}
+
+		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
+			handler.ServeHTTP(w, r)
+			return
+		}
+		w.Header().Set("Content-Encoding", "gzip")
+		gz := gzip.NewWriter(w)
+		defer gz.Close()
+		gzw := gzipResponseWriter{Writer: gz, ResponseWriter: w}
+		handler.ServeHTTP(gzw, r)
+	})
+}

pkg/api/server.go

@@ -147,9 +147,11 @@ func (s *Server) startHTTP() error {
 		return errors.Wrap(err, "creating grpc-gateway listener")
 	}
 
+	// Add two handler wrappers to mux: gzipWrapper and allowCORS
 	server := http.Server{
 		Addr:    addr,
-		Handler: allowCORS(mux),
+		Handler: allowCORS(gzipWrapper(mux)),
+		//		Handler: gzipWrapper(allowCORS(mux)),
 	}
 
 	tracing.GoPanicWrap(s.ctx, &s.wg, "http", func(ctx context.Context) {

pkg/api/server_test.go

@@ -118,7 +118,7 @@ func Test_QueryNoTopics(t *testing.T) {
 			require.Equal(t, codes.InvalidArgument, grpcErr.Code())
 			require.EqualError(t, err, `rpc error: code = InvalidArgument desc = content topics required`)
 		} else {
-			require.EqualError(t, err, "400 Bad Request: {\"code\":3, \"message\":\"content topics required\", \"details\":[]}")
+			require.Regexp(t, `400 Bad Request: {"code\":3,\s?"message":"content topics required",\s?"details":\[\]}`, err.Error())
 		}
 		require.Nil(t, queryRes)
 	})