common/prpc, tools/cmd/cproto: prpc client

common/prpc/codes.go

Index: common/prpc/codes.go
diff --git a/common/prpc/codes.go b/common/prpc/codes.go
new file mode 100644
index 0000000000000000000000000000000000000000..1f1cf17b2718470b13bf189148fb10932b184b58
--- /dev/null
+++ b/common/prpc/codes.go
@@ -0,0 +1,48 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package prpc
+
+import (
+	"net/http"
+
+	"google.golang.org/grpc/codes"
+)
+
+// StatusCode maps HTTP statuses to gRPC codes.
+// Falls back to codes.Unknown.
+//
+// The behavior of this function may change when
+// https://github.com/grpc/grpc-common/issues/210
+// is closed.
+func StatusCode(status int) codes.Code {
+	switch {
+
+	case status >= 200 && status < 300:
+		return codes.OK
+
+	case status == http.StatusUnauthorized:
+		return codes.Unauthenticated
+	case status == http.StatusForbidden:
+		return codes.PermissionDenied
+	case status == http.StatusNotFound:
+		return codes.NotFound
+	case status == http.StatusGone:
+		return codes.NotFound
+	case status == http.StatusPreconditionFailed:
+		return codes.FailedPrecondition
+	case status >= 400 && status < 500:
+		return codes.InvalidArgument
+
+	case status == http.StatusNotImplemented:
+		return codes.Unimplemented
+	case status == http.StatusServiceUnavailable:
+		return codes.Unavailable
+	case status >= 500 && status < 600:
+		return codes.Internal
+
+	default:
+		return codes.Unknown
+	}
+}