grpc-go/internal/testutils/state.go

86 lines
2.7 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 testutils
import (
"context"
"testing"
"google.golang.org/grpc/connectivity"
)
// A StateChanger reports state changes, e.g. a grpc.ClientConn.
type StateChanger interface {
// Connect begins connecting the StateChanger.
Connect()
// GetState returns the current state of the StateChanger.
GetState() connectivity.State
// WaitForStateChange returns true when the state becomes s, or returns
// false if ctx is canceled first.
WaitForStateChange(ctx context.Context, s connectivity.State) bool
}
// StayConnected makes sc stay connected by repeatedly calling sc.Connect()
// until the state becomes Shutdown or until the context expires.
func StayConnected(ctx context.Context, sc StateChanger) {
for {
state := sc.GetState()
switch state {
case connectivity.Idle:
sc.Connect()
case connectivity.Shutdown:
return
}
if !sc.WaitForStateChange(ctx, state) {
return
}
}
}
// AwaitState waits for sc to enter stateWant or fatal errors if it doesn't
// happen before ctx expires.
func AwaitState(ctx context.Context, t *testing.T, sc StateChanger, stateWant connectivity.State) {
t.Helper()
for state := sc.GetState(); state != stateWant; state = sc.GetState() {
if !sc.WaitForStateChange(ctx, state) {
t.Fatalf("Timed out waiting for state change. got %v; want %v", state, stateWant)
}
}
}
// AwaitNotState waits for sc to leave stateDoNotWant or fatal errors if it
// doesn't happen before ctx expires.
func AwaitNotState(ctx context.Context, t *testing.T, sc StateChanger, stateDoNotWant connectivity.State) {
t.Helper()
for state := sc.GetState(); state == stateDoNotWant; state = sc.GetState() {
if !sc.WaitForStateChange(ctx, state) {
t.Fatalf("Timed out waiting for state change. got %v; want NOT %v", state, stateDoNotWant)
}
}
}
// AwaitNoStateChange expects ctx to be canceled before sc's state leaves
// currState, and fatal errors otherwise.
func AwaitNoStateChange(ctx context.Context, t *testing.T, sc StateChanger, currState connectivity.State) {
t.Helper()
if sc.WaitForStateChange(ctx, currState) {
t.Fatalf("State changed from %q to %q when no state change was expected", currState, sc.GetState())
}
}