68 lines
1.3 KiB
Go
68 lines
1.3 KiB
Go
//go:build !solution
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package retryupdate
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import (
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"errors"
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"fmt"
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"github.com/gofrs/uuid"
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"gitlab.com/slon/shad-go/retryupdate/kvapi"
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)
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var (
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authError *kvapi.AuthError
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conflictError *kvapi.ConflictError
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)
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func UpdateValue(c kvapi.Client, key string, updateFn func(oldValue *string) (newValue string, err error)) error {
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newVersion := uuid.Must(uuid.NewV4())
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get:
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for {
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old, err := c.Get(&kvapi.GetRequest{Key: key})
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var value *string
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oldUuid := uuid.Nil
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if err != nil {
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switch {
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case errors.As(err, &authError):
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return err
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case !errors.Is(err, kvapi.ErrKeyNotFound):
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continue
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}
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} else {
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value = &old.Value
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oldUuid = old.Version
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}
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for {
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new, err := updateFn(value)
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if err != nil {
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return err
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}
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_, err = c.Set(&kvapi.SetRequest{
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Key: key,
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Value: new,
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OldVersion: oldUuid,
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NewVersion: newVersion,
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})
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if err != nil {
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fmt.Println(err)
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switch {
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case errors.As(err, &conflictError):
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if conflictError.ExpectedVersion == newVersion {
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return nil
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}
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continue get
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case errors.Is(err, kvapi.ErrKeyNotFound):
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value = nil
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oldUuid = uuid.Nil
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continue
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case errors.As(err, &authError):
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return err
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default:
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continue
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}
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}
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return nil
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}
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}
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}
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