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

common/prpc/client_test.go

+// 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 (
+        "fmt"
+        "io/ioutil"
+        "net/http"
+        "net/http/httptest"
+        "strconv"
+        "strings"
+        "testing"
+        "time"
+
+        "github.com/golang/protobuf/proto"
+        "golang.org/x/net/context"
+        "google.golang.org/grpc"
+        "google.golang.org/grpc/codes"
+
+        "github.com/luci/luci-go/common/logging"
+        "github.com/luci/luci-go/common/logging/memlogger"
+        "github.com/luci/luci-go/common/retry"
+
+        . "github.com/luci/luci-go/common/testing/assertions"
+        . "github.com/smartystreets/goconvey/convey"
+)
+
+func sayHello(c C) http.HandlerFunc {
+        return func(w http.ResponseWriter, r *http.Request) {
+                c.So(r.Method, ShouldEqual, "POST")
+                c.So(r.URL.Path, ShouldEqual, "/prpc/prpc.Greeter/SayHello")
+                c.So(r.Header.Get("Accept"), ShouldEqual, "application/prpc")
+                c.So(r.Header.Get("Content-Type"), ShouldEqual, "application/prpc")
+                c.So(r.Header.Get("User-Agent"), ShouldEqual, "prpc-test")
+
+                reqBody, err := ioutil.ReadAll(r.Body)
+                c.So(err, ShouldBeNil)
+
+                var req HelloRequest
+                err = proto.Unmarshal(reqBody, &req)
+                c.So(err, ShouldBeNil)
+
+                res := HelloReply{"Hello " + req.Name}
+                buf, err := proto.Marshal(&res)
+                c.So(err, ShouldBeNil)
+
+                _, err = w.Write(buf)
+                c.So(err, ShouldBeNil)
+        }
+}
+
+func transientErrors(count int, then http.Handler) http.HandlerFunc {
+        return func(w http.ResponseWriter, r *http.Request) {
+                if count > 0 {
+                        count--
+                        w.WriteHeader(http.StatusInternalServerError)
+                        fmt.Fprintln(w, "Server misbehaved")
+                        return
+                }
+                then.ServeHTTP(w, r)
+        }
+}
+
+func shouldHaveMessagesLike(actual interface{}, expected ...interface{}) string {
+        log := actual.(*memlogger.MemLogger)
+        msgs := log.Messages()
+
+        So(msgs, ShouldHaveLength, len(expected))
+        for i, actual := range msgs {
+                expected := expected[i].(memlogger.LogEntry)
+                So(actual.Level, ShouldEqual, expected.Level)
+                So(actual.Msg, ShouldContainSubstring, expected.Msg)
+        }
+        return ""
+}
+
+func TestClient(t *testing.T) {
+        t.Parallel()
+
+        Convey("Client", t, func() {
+                setUp := func(h http.HandlerFunc) (*Client, *httptest.Server) {
+                        server := httptest.NewServer(h)
+                        client := &Client{
+                                Host: strings.TrimPrefix(server.URL, "http://"),
+                                Options: &Options{
+                                        Retry: func() retry.Iterator {
+                                                return &retry.ExponentialBackoff{
+                                                        Limited: retry.Limited{
+                                                                Retries: 3,
+                                                                Delay:   time.Millisecond,
+                                                        },
+                                                }
+                                        },
+                                        Insecure:  true,
+                                        UserAgent: "prpc-test",
+                                },
+                        }
+                        return client, server
+                }
+
+                ctx := memlogger.Use(context.Background())
+                log := logging.Get(ctx).(*memlogger.MemLogger)
+                expectedCallLogEntry := func(c *Client) memlogger.LogEntry {
+                        return memlogger.LogEntry{
+                                Level: logging.Debug,
+                                Msg:   fmt.Sprintf("RPC %s/prpc.Greeter.SayHello", c.Host),
+                        }
+                }
+
+                req := &HelloRequest{"John"}
+                res := &HelloReply{}
+
+                Convey("Call", func() {
+                        Convey("Works", func(c C) {
+                                client, server := setUp(sayHello(c))
+                                defer server.Close()
+
+                                err := client.Call(ctx, "prpc.Greeter", "SayHello", req, res)
+                                So(err, ShouldBeNil)
+                                So(res.Message, ShouldEqual, "Hello John")
+
+                                So(log, shouldHaveMessagesLike, expectedCallLogEntry(client))
+                        })
+
+                        Convey("HTTP 500 x2", func(c C) {
+                                client, server := setUp(transientErrors(2, sayHello(c)))
+                                defer server.Close()
+
+                                err := client.Call(ctx, "prpc.Greeter", "SayHello", req, res)
+                                So(err, ShouldBeNil)
+                                So(res.Message, ShouldEqual, "Hello John")
+
+                                So(log, shouldHaveMessagesLike,
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed transiently. Will retry in 1ms"},
+
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed transiently. Will retry in 2ms"},
+
+                                        expectedCallLogEntry(client),
+                                )
+                        })
+
+                        Convey("HTTP 500 many", func(c C) {
+                                client, server := setUp(transientErrors(10, sayHello(c)))
+                                defer server.Close()
+
+                                err := client.Call(ctx, "prpc.Greeter", "SayHello", req, res)
+                                So(err, ShouldErrLike, "HTTP 500 Internal Server Error: Server misbehaved")
+                                So(grpc.Code(err), ShouldEqual, codes.Internal)
+
+                                So(log, shouldHaveMessagesLike,
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed transiently. Will retry in 1ms"},
+
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed transiently. Will retry in 2ms"},
+
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed transiently. Will retry in 4ms"},
+
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed permanently"},
+                                )
+                        })
+
+                        Convey("HTTP 403 x10", func(c C) {
+                                client, server := setUp(func(w http.ResponseWriter, r *http.Request) {
+                                        w.WriteHeader(http.StatusForbidden)
+                                })
+                                defer server.Close()
+
+                                err := client.Call(ctx, "prpc.Greeter", "SayHello", req, res)
+                                So(err, ShouldErrLike, "HTTP 403")
+                                So(grpc.Code(err), ShouldEqual, codes.PermissionDenied)
+
+                                So(log, shouldHaveMessagesLike,
+                                        expectedCallLogEntry(client),
+                                        memlogger.LogEntry{Level: logging.Warning, Msg: "RPC failed permanently"},
+                                )
+                        })
+
+                        Convey(HeaderGrpcCode, func(c C) {
+                                client, server := setUp(func(w http.ResponseWriter, r *http.Request) {
+                                        w.Header().Set(HeaderGrpcCode, strconv.Itoa(int(codes.Canceled)))
+                                        w.WriteHeader(http.StatusBadRequest)
+                                })
+                                defer server.Close()
+
+                                err := client.Call(ctx, "prpc.Greeter", "SayHello", req, res)
+                                So(grpc.Code(err), ShouldEqual, codes.Canceled)
+                        })
+                })
+        })
+}