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idem

package module

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Versions in this module

v0

v0.1.0

Oct 2, 2026

Changes in this version

+ const DefaultLease

+ const DefaultTTL

+ var ErrFingerprintMismatch = errors.New("idem: key was already used with a different request")

+ var ErrInProgress = errors.New("idem: an operation with this key is already in progress")

+ var ErrInvalidKey = errors.New("idem: invalid key")

+ var ErrLeaseLost = errors.New("idem: lease lost")

+ var ErrNotRecorded = errors.New("idem: operation finished but its result was not recorded")

+ func Do[T any](ctx context.Context, e *Engine, key string, ...) (v T, replayed bool, err error)

+ func Fingerprint(parts ...[]byte) string

+ func Provisional(ctx context.Context) context.Context

+ type Attempt struct

+ func (a *Attempt) Complete(ctx context.Context, result []byte) error

+ func (a *Attempt) Context() context.Context

+ func (a *Attempt) Key() string

+ func (a *Attempt) Release(ctx context.Context) error

+ func (a *Attempt) Token() string

+ type Claim struct

+ Fingerprint string

+ Result []byte

+ State State

+ type Codec interface

+ Marshal func(v any) ([]byte, error)

+ Unmarshal func(data []byte, v any) error

+ type Engine struct

+ func New(store Store, opts ...Option) *Engine

+ func (e *Engine) Begin(ctx context.Context, key string, opts ...Option) (*Attempt, []byte, error)

+ func (e *Engine) Codec() Codec

+ func (e *Engine) Store() Store

+ type Option func(*config)

+ func WithCodec(codec Codec) Option

+ func WithFingerprint(fp string) Option

+ func WithHeartbeat(d time.Duration) Option

+ func WithLease(d time.Duration) Option

+ func WithNamespace(ns string) Option

+ func WithTTL(d time.Duration) Option

+ func WithWait(d time.Duration) Option

+ type State int

+ const StateAcquired

+ const StateCompleted

+ const StateInProgress

+ func (s State) String() string

+ type Store interface

+ Acquire func(ctx context.Context, key, token, fingerprint string, lease time.Duration) (Claim, error)

+ Complete func(ctx context.Context, key, token string, result []byte, ttl time.Duration) error

+ Extend func(ctx context.Context, key, token string, lease time.Duration) error

+ Release func(ctx context.Context, key, token string) error