woodpecker/agent/rpc/auth_interceptor.go
2023-09-16 10:53:37 +02:00

113 lines
2.8 KiB
Go

// Copyright 2023 Woodpecker 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 rpc
import (
"context"
"time"
"github.com/rs/zerolog/log"
"google.golang.org/grpc"
"google.golang.org/grpc/metadata"
)
// AuthInterceptor is a client interceptor for authentication
type AuthInterceptor struct {
authClient *AuthClient
accessToken string
}
// NewAuthInterceptor returns a new auth interceptor
func NewAuthInterceptor(
authClient *AuthClient,
refreshDuration time.Duration,
) (*AuthInterceptor, error) {
interceptor := &AuthInterceptor{
authClient: authClient,
}
err := interceptor.scheduleRefreshToken(refreshDuration)
if err != nil {
return nil, err
}
return interceptor, nil
}
// Unary returns a client interceptor to authenticate unary RPC
func (interceptor *AuthInterceptor) Unary() grpc.UnaryClientInterceptor {
return func(
ctx context.Context,
method string,
req, reply interface{},
cc *grpc.ClientConn,
invoker grpc.UnaryInvoker,
opts ...grpc.CallOption,
) error {
return invoker(interceptor.attachToken(ctx), method, req, reply, cc, opts...)
}
}
// Stream returns a client interceptor to authenticate stream RPC
func (interceptor *AuthInterceptor) Stream() grpc.StreamClientInterceptor {
return func(
ctx context.Context,
desc *grpc.StreamDesc,
cc *grpc.ClientConn,
method string,
streamer grpc.Streamer,
opts ...grpc.CallOption,
) (grpc.ClientStream, error) {
return streamer(interceptor.attachToken(ctx), desc, cc, method, opts...)
}
}
func (interceptor *AuthInterceptor) attachToken(ctx context.Context) context.Context {
return metadata.AppendToOutgoingContext(ctx, "token", interceptor.accessToken)
}
func (interceptor *AuthInterceptor) scheduleRefreshToken(refreshDuration time.Duration) error {
err := interceptor.refreshToken()
if err != nil {
return err
}
go func() {
wait := refreshDuration
for {
time.Sleep(wait)
err := interceptor.refreshToken()
if err != nil {
wait = time.Second
} else {
wait = refreshDuration
}
}
}()
return nil
}
func (interceptor *AuthInterceptor) refreshToken() error {
accessToken, _, err := interceptor.authClient.Auth()
if err != nil {
return err
}
interceptor.accessToken = accessToken
log.Trace().Msg("token refreshed")
return nil
}