grpc-go/interop/xds/custom_lb_test.go

136 lines
4.2 KiB
Go

/*
*
* Copyright 2023 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package xds
import (
"context"
"errors"
"fmt"
"testing"
"time"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
"google.golang.org/grpc/internal"
"google.golang.org/grpc/internal/grpctest"
"google.golang.org/grpc/internal/stubserver"
"google.golang.org/grpc/internal/testutils"
testgrpc "google.golang.org/grpc/interop/grpc_testing"
testpb "google.golang.org/grpc/interop/grpc_testing"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/resolver"
"google.golang.org/grpc/resolver/manual"
"google.golang.org/grpc/serviceconfig"
)
var defaultTestTimeout = 5 * time.Second
type s struct {
grpctest.Tester
}
func Test(t *testing.T) {
grpctest.RunSubTests(t, s{})
}
// TestCustomLB tests the Custom LB for the interop client. It configures the
// custom lb as the top level Load Balancing policy of the channel, then asserts
// it can successfully make an RPC and also that the rpc behavior the Custom LB
// is configured with makes it's way to the server in metadata.
func (s) TestCustomLB(t *testing.T) {
errCh := testutils.NewChannel()
// Setup a backend which verifies the expected rpc-behavior metadata is
// present in the request.
backend := &stubserver.StubServer{
UnaryCallF: func(ctx context.Context, _ *testpb.SimpleRequest) (*testpb.SimpleResponse, error) {
md, ok := metadata.FromIncomingContext(ctx)
if !ok {
errCh.Send(errors.New("failed to receive metadata"))
return &testpb.SimpleResponse{}, nil
}
rpcBMD := md.Get("rpc-behavior")
if len(rpcBMD) != 1 {
errCh.Send(fmt.Errorf("received %d values for metadata key \"rpc-behavior\", want 1", len(rpcBMD)))
return &testpb.SimpleResponse{}, nil
}
wantVal := "error-code-0"
if rpcBMD[0] != wantVal {
errCh.Send(fmt.Errorf("metadata val for key \"rpc-behavior\": got val %v, want val %v", rpcBMD[0], wantVal))
return &testpb.SimpleResponse{}, nil
}
// Success.
errCh.Send(nil)
return &testpb.SimpleResponse{}, nil
},
}
if err := backend.StartServer(); err != nil {
t.Fatalf("Failed to start backend: %v", err)
}
t.Logf("Started good TestService backend at: %q", backend.Address)
defer backend.Stop()
lbCfgJSON := `{
"loadBalancingConfig": [
{
"test.RpcBehaviorLoadBalancer": {
"rpcBehavior": "error-code-0"
}
}
]
}`
sc := internal.ParseServiceConfig.(func(string) *serviceconfig.ParseResult)(lbCfgJSON)
mr := manual.NewBuilderWithScheme("customlb-e2e")
defer mr.Close()
mr.InitialState(resolver.State{
Addresses: []resolver.Address{
{Addr: backend.Address},
},
ServiceConfig: sc,
})
cc, err := grpc.NewClient(mr.Scheme()+":///", grpc.WithResolvers(mr), grpc.WithTransportCredentials(insecure.NewCredentials()))
if err != nil {
t.Fatalf("grpc.NewClient() failed: %v", err)
}
defer cc.Close()
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
testServiceClient := testgrpc.NewTestServiceClient(cc)
// Make a Unary RPC. This RPC should be successful due to the round_robin
// leaf balancer. Also, the custom load balancer should inject the
// "rpc-behavior" string it is configured with into the metadata sent to
// server.
if _, err := testServiceClient.UnaryCall(ctx, &testpb.SimpleRequest{}); err != nil {
t.Fatalf("EmptyCall() failed: %v", err)
}
val, err := errCh.Receive(ctx)
if err != nil {
t.Fatalf("error receiving from errCh: %v", err)
}
// Should receive nil on the error channel which implies backend verified it
// correctly received the correct "rpc-behavior" metadata.
if err, ok := val.(error); ok {
t.Fatalf("error in backend verifications on metadata received: %v", err)
}
}