Documentation
¶
Overview ¶
Package exp contains experimental unstable features.
Example ¶
//go:build go1.13
// +build go1.13
package main
import (
"context"
"database/sql"
"errors"
"fmt"
"math/rand"
"net"
"time"
"github.com/kamilsk/retry/sandbox"
"github.com/kamilsk/retry/v5"
"github.com/kamilsk/retry/v5/backoff"
"github.com/kamilsk/retry/v5/jitter"
"github.com/kamilsk/retry/v5/strategy"
)
var generator = rand.New(rand.NewSource(0))
func main() {
what := SendRequest
how := retry.How{
strategy.Limit(5),
strategy.BackoffWithJitter(
backoff.Fibonacci(10*time.Millisecond),
jitter.NormalDistribution(
rand.New(rand.NewSource(time.Now().UnixNano())),
0.25,
),
),
// experimental
sandbox.CheckError(
sandbox.NetworkError(sandbox.Skip),
DatabaseError(),
),
}
breaker, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
if err := retry.Do(breaker, what, how...); err != nil {
panic(err)
}
fmt.Println("success communication")
}
func SendRequest(ctx context.Context) error {
select {
case <-ctx.Done():
return ctx.Err()
default:
}
if generator.Intn(5) > 3 {
return &net.DNSError{Name: "unknown host", IsTemporary: true}
}
return nil
}
func DatabaseError() func(error) bool {
deprecated := []error{sql.ErrNoRows, sql.ErrConnDone, sql.ErrTxDone}
return func(err error) bool {
for _, deprecated := range deprecated {
if errors.Is(err, deprecated) {
return false
}
}
return true
}
}
Output: success communication
Index ¶
Examples ¶
Constants ¶
const ( Skip = true Stop = false )
Variables ¶
This section is empty.
Functions ¶
func CheckError ¶
CheckError creates a Strategy that checks an error and returns if an error is retriable or not. Otherwise, it returns the defaults.
func NetworkError ¶
NetworkError creates an error Handler that checks an error and returns true if an error is the temporary network error. The Handler returns the defaults if an error is not a network error.
Types ¶
type Breaker ¶
type Breaker = interface {
// Done returns a channel that's closed when a cancellation signal occurred.
Done() <-chan struct{}
// If Done is not yet closed, Err returns nil.
// If Done is closed, Err returns a non-nil error.
// After Err returns a non-nil error, successive calls to Err return the same error.
Err() error
}
A Breaker carries a cancellation signal to interrupt an action execution.
It is a subset of the built-in context and github.com/kamilsk/breaker interfaces.
type ErrorHandler ¶
ErrorHandler defines a function that CheckError calls to determine whether it should make the next attempt or not. Returning true allows for the next attempt to be made. Returning false halts the retrying process and returns the last error returned by the called Action.
Source Files