lock

Documentation

Index

• Variables
• type Client
  • func New(ddb storageI, table string) *Client
  • func NewTestClient(t *testing.T) *Client
  • func (c *Client) Lock(ctx context.Context, key string, expire time.Duration) error
  • func (c *Client) Locked(ctx context.Context, key string) (bool, error)
  • func (c *Client) Run(ctx context.Context, key, command string) (string, error)
  • func (c *Client) Unlock(ctx context.Context, key string) error

Variables

var (
	// ErrLocked when locking an key that is already locked.
	ErrLocked = errors.New("key is locked")
)

Types

type Client

type Client struct {
	// contains filtered or unexported fields
}

Client holds lock configuration.

func New

func New(ddb storageI, table string) *Client

New creates a new lock client.

func NewTestClient

func NewTestClient(t *testing.T) *Client

NewTestClient returns a test client with in-memory storage that can be used for lock testing.

func (*Client) Lock

func (c *Client) Lock(ctx context.Context, key string, expire time.Duration) error

Lock creates a new lock with "key" as a unique identifier. The lock will expire after the specified duration. Returns ErrLocked if the lock already exists and has not expired.

func (*Client) Locked

func (c *Client) Locked(ctx context.Context, key string) (bool, error)

Locked checks if the current key is locked.

func (*Client) Run

func (c *Client) Run(ctx context.Context, key, command string) (string, error)

Run acquires a lock under the specified key, executes the command, and then unlocks the key. Returns ErrLocked if the key is already locked. Otherwise returns combined stdout and stderr of the command and the command error. If the unlock step fails the lock expires after 24 hours.

func (*Client) Unlock

func (c *Client) Unlock(ctx context.Context, key string) error

Unlock releases an existing lock of the specified key. Does not error if the lock doesn't exist.