mirror of https://github.com/grpc/grpc-go.git
83 lines
2.8 KiB
Go
83 lines
2.8 KiB
Go
/*
|
|
*
|
|
* Copyright 2022 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 pickfirst contains helper functions to check for pickfirst load
|
|
// balancing of RPCs in tests.
|
|
package pickfirst
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"time"
|
|
|
|
"google.golang.org/grpc"
|
|
"google.golang.org/grpc/peer"
|
|
"google.golang.org/grpc/resolver"
|
|
|
|
testgrpc "google.golang.org/grpc/interop/grpc_testing"
|
|
testpb "google.golang.org/grpc/interop/grpc_testing"
|
|
)
|
|
|
|
// CheckRPCsToBackend makes a bunch of RPCs on the given ClientConn and verifies
|
|
// if the RPCs are routed to a peer matching wantAddr.
|
|
//
|
|
// Returns a non-nil error if context deadline expires before all RPCs begin to
|
|
// be routed to the peer matching wantAddr, or if the backend returns RPC errors.
|
|
func CheckRPCsToBackend(ctx context.Context, cc *grpc.ClientConn, wantAddr resolver.Address) error {
|
|
client := testgrpc.NewTestServiceClient(cc)
|
|
peer := &peer.Peer{}
|
|
// Make sure that 20 RPCs in a row reach the expected backend. Some
|
|
// tests switch from round_robin back to pick_first and call this
|
|
// function. None of our tests spin up more than 10 backends. So,
|
|
// waiting for 20 RPCs to reach a single backend would a decent
|
|
// indicator of having switched to pick_first.
|
|
count := 0
|
|
for {
|
|
time.Sleep(time.Millisecond)
|
|
if ctx.Err() != nil {
|
|
return fmt.Errorf("timeout waiting for RPC to be routed to %s", wantAddr.Addr)
|
|
}
|
|
if _, err := client.EmptyCall(ctx, &testpb.Empty{}, grpc.Peer(peer)); err != nil {
|
|
// Some tests remove backends and check if pick_first is happening across
|
|
// the remaining backends. In such cases, RPCs can initially fail on the
|
|
// connection using the removed backend. Just keep retrying and eventually
|
|
// the connection using the removed backend will shutdown and will be
|
|
// removed.
|
|
continue
|
|
}
|
|
if peer.Addr.String() != wantAddr.Addr {
|
|
count = 0
|
|
continue
|
|
}
|
|
count++
|
|
if count > 20 {
|
|
break
|
|
}
|
|
}
|
|
// Make sure subsequent RPCs are all routed to the same backend.
|
|
for i := 0; i < 10; i++ {
|
|
if _, err := client.EmptyCall(ctx, &testpb.Empty{}, grpc.Peer(peer)); err != nil {
|
|
return fmt.Errorf("EmptyCall() = %v, want <nil>", err)
|
|
}
|
|
if gotAddr := peer.Addr.String(); gotAddr != wantAddr.Addr {
|
|
return fmt.Errorf("rpc sent to peer %q, want peer %q", gotAddr, wantAddr)
|
|
}
|
|
}
|
|
return nil
|
|
}
|