json

Documentation

Index

• type Store
  • func New[T any](filePath string, locker lock.Locker) *Store[T]
  • func (s *Store[T]) ReadRaw(fn func(*T) error) error
  • func (s *Store[T]) TryLock(ctx context.Context) (bool, error)
  • func (s *Store[T]) Unlock(ctx context.Context) error
  • func (s *Store[T]) Update(ctx context.Context, fn func(*T) error) error
  • func (s *Store[T]) With(ctx context.Context, fn func(*T) error) error
  • func (s *Store[T]) WriteRaw(fn func(*T) error) error

Types

type Store

type Store[T any] struct {
	// contains filtered or unexported fields
}

Store provides locked read/modify/write access to a JSON file. T is the top-level structure stored in the file (must have exported fields with json tags). If *T implements storage.Initer, Init() is called automatically after loading. The caller provides the Locker, decoupling storage from any specific lock implementation.

func New

func New[T any](filePath string, locker lock.Locker) *Store[T]

New creates a Store backed by filePath, using locker for mutual exclusion.

func (*Store[T]) ReadRaw

func (s *Store[T]) ReadRaw(fn func(*T) error) error

ReadRaw deserializes the JSON file and passes the data to fn. The caller must already hold the lock (via TryLock).

func (*Store[T]) TryLock

func (s *Store[T]) TryLock(ctx context.Context) (bool, error)

TryLock delegates to the underlying locker.

func (*Store[T]) Unlock

func (s *Store[T]) Unlock(ctx context.Context) error

Unlock delegates to the underlying locker.

func (*Store[T]) Update

func (s *Store[T]) Update(ctx context.Context, fn func(*T) error) error

Update acquires the lock (blocking), calls Write under lock, then releases. If fn returns nil the data is atomically persisted.

func (*Store[T]) With

func (s *Store[T]) With(ctx context.Context, fn func(*T) error) error

With acquires the lock (blocking), calls Read under lock, then releases.

func (*Store[T]) WriteRaw

func (s *Store[T]) WriteRaw(fn func(*T) error) error

WriteRaw deserializes the JSON file, passes the data to fn, and atomically persists the result if fn returns nil. The caller must already hold the lock (via TryLock).