go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/common/retry/defaults.go (about)

     1  // Copyright 2015 The LUCI Authors.
     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 retry
    16  
    17  import (
    18  	"context"
    19  	"time"
    20  )
    21  
    22  // defaultIterator defines a template for the default retry parameters that
    23  // should be used throughout the program.
    24  var defaultIteratorTemplate = ExponentialBackoff{
    25  	Limited: Limited{
    26  		Delay:   200 * time.Millisecond,
    27  		Retries: 10,
    28  	},
    29  	MaxDelay:   10 * time.Second,
    30  	Multiplier: 2,
    31  }
    32  
    33  // Default is a Factory that returns a new instance of the default iterator
    34  // configuration.
    35  func Default() Iterator {
    36  	it := defaultIteratorTemplate
    37  	return &it
    38  }
    39  
    40  type noneItTemplate struct{}
    41  
    42  func (noneItTemplate) Next(context.Context, error) time.Duration { return Stop }
    43  
    44  // None is a Factory that returns an Iterator that explicitly calls Stop after
    45  // the first try. This is helpful to pass to libraries which use retry.Default
    46  // if given nil, but where you don't want any retries at all (e.g. tests).
    47  func None() Iterator {
    48  	return noneItTemplate{}
    49  }