github.com/livekit/protocol@v1.39.3/utils/retry.go (about)

     1  // Copyright 2023 LiveKit, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package utils
    16  
    17  import (
    18  	"context"
    19  	"errors"
    20  	"math/rand/v2"
    21  	"time"
    22  )
    23  
    24  type terminalError struct {
    25  	error
    26  }
    27  
    28  func (e terminalError) Unwrap() error {
    29  	return e.error
    30  }
    31  
    32  func TerminalError(err error) error {
    33  	return terminalError{err}
    34  }
    35  
    36  func ErrIsTerminal(err error) bool {
    37  	var terr terminalError
    38  	return errors.As(err, &terr)
    39  }
    40  
    41  func Retry(ctx context.Context, minTime, maxTime, timeout time.Duration, f func(ctx context.Context) error) error {
    42  	retryTime := minTime
    43  
    44  	ctx, cancel := context.WithTimeout(ctx, timeout)
    45  	defer cancel()
    46  
    47  	for {
    48  		err := f(ctx)
    49  		if err == nil || ErrIsTerminal(err) {
    50  			return err
    51  		}
    52  
    53  		select {
    54  		case <-ctx.Done():
    55  			return err
    56  		case <-time.After(retryTime):
    57  		}
    58  
    59  		retryTime = min(maxTime, time.Duration((rand.Float64()+1)*float64(retryTime)))
    60  	}
    61  }