Merge pull request #20 from tukeJonny/retrier-runctx
Add RunCtx to retrier
Evan Huus authored 5 years ago
GitHub committed 5 years ago
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language: go
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go:
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- 1.2
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- 1.6
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- 1.10
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- 1.7
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- "1.10"
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package retrier
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import (
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"context"
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"math/rand"
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"sync"
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"time"
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}
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}
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// Run executes the given work function, then classifies its return value based on the classifier used
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// Run executes the given work function by executing RunCtx without context.Context.
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func (r *Retrier) Run(work func() error) error {
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return r.RunCtx(context.Background(), func(ctx context.Context) error {
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// never use ctx
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return work()
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})
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}
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// RunCtx executes the given work function, then classifies its return value based on the classifier used
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// to construct the Retrier. If the result is Succeed or Fail, the return value of the work function is
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// returned to the caller. If the result is Retry, then Run sleeps according to the its backoff policy
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// before retrying. If the total number of retries is exceeded then the return value of the work function
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// is returned to the caller regardless.
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func (r *Retrier) Run(work func() error) error {
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func (r *Retrier) RunCtx(ctx context.Context, work func(ctx context.Context) error) error {
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retries := 0
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for {
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ret := work()
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ret := work(ctx)
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switch r.class.Classify(ret) {
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case Succeed, Fail:
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if retries >= len(r.backoff) {
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return ret
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}
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time.Sleep(r.calcSleep(retries))
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timeout := time.After(r.calcSleep(retries))
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if err := r.sleep(ctx, timeout); err != nil {
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return err
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}
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retries++
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}
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}
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}
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func (r *Retrier) sleep(ctx context.Context, t <-chan time.Time) error {
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select {
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case <-t:
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return nil
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case <-ctx.Done():
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return ctx.Err()
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}
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}
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package retrier
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import (
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"context"
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"errors"
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"testing"
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"time"
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return nil
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}
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return returns[i-1]
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}
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}
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func genWorkWithCtx() func(ctx context.Context) error {
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i = 0
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return func(ctx context.Context) error {
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select {
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case <-ctx.Done():
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return errFoo
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default:
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i++
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}
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return nil
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}
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}
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t.Error(err)
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}
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if i != 1 {
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t.Error("run wrong number of times")
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}
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}
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func TestRetrierCtx(t *testing.T) {
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ctx, cancel := context.WithCancel(context.Background())
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r := New([]time.Duration{0, 10 * time.Millisecond}, WhitelistClassifier{})
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err := r.RunCtx(ctx, genWorkWithCtx())
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if err != nil {
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t.Error(err)
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}
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if i != 1 {
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t.Error("run wrong number of times")
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}
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cancel()
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err = r.RunCtx(ctx, genWorkWithCtx())
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if err != errFoo {
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t.Error("context must be cancelled")
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}
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if i != 0 {
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t.Error("run wrong number of times")
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}
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}
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