zookeeper

Documentation

Index

• Variables
• func EnsureZkFatjar()
• type Connection
  • func (c *Connection) Children(path string) (children []string, err error)
  • func (c *Connection) ChildrenW(path string) (children []string, event <-chan client.Event, err error)
  • func (c *Connection) Close()
  • func (c *Connection) Create(path string, node client.Node) error
  • func (c *Connection) CreateDir(path string) error
  • func (c *Connection) CreateEphemeral(path string, node client.Node) (string, error)
  • func (c *Connection) Delete(path string) error
  • func (c *Connection) Exists(path string) (bool, error)
  • func (c *Connection) Get(path string, node client.Node) (err error)
  • func (c *Connection) GetW(path string, node client.Node) (event <-chan client.Event, err error)
  • func (c *Connection) ID() int
  • func (c *Connection) NewLeader(path string, node client.Node) client.Leader
  • func (c *Connection) NewLock(path string) client.Lock
  • func (c *Connection) Set(path string, node client.Node) error
  • func (c *Connection) SetID(id int)
  • func (c *Connection) SetOnClose(f func(int))
• type DSN
  • func NewDSN(servers []string, timeout time.Duration) DSN
  • func ParseDSN(dsn string) (val DSN, err error)
  • func (dsn DSN) String() string
• type Driver
  • func (driver *Driver) GetConnection(dsn, basePath string) (client.Connection, error)
• type Leader
  • func (l *Leader) Current(node client.Node) (err error)
  • func (l *Leader) ReleaseLead() error
  • func (l *Leader) TakeLead() (echan <-chan client.Event, err error)
• type Lock
  • func (l *Lock) Lock() (err error)
  • func (l *Lock) Unlock() error

Variables

var (
	// ErrDeadlock is returned when a lock is aquired twice on the same object.
	ErrDeadlock = errors.New("zk: trying to acquire a lock twice")

	// ErrNotLocked is returned when a caller attempts to release a lock that
	// has not been aquired
	ErrNotLocked = errors.New("zk: not locked")

	// ErrNoLeaderFound is returned when a leader has not been elected
	ErrNoLeaderFound = errors.New("zk: no leader found")
)

Functions

func EnsureZkFatjar

func EnsureZkFatjar()

EnsureZkFatjar downloads the zookeeper binaries for use in unit tests

Types

type Connection

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

Connection is a Zookeeper based implementation of client.Connection.

func (*Connection) Children

func (c *Connection) Children(path string) (children []string, err error)

Children returns the children of the node at the given path.

func (*Connection) ChildrenW

func (c *Connection) ChildrenW(path string) (children []string, event <-chan client.Event, err error)

ChildrenW returns the children of the node at the give path and a channel of events that will yield the next event at that node.

func (*Connection) Close

func (c *Connection) Close()

Close the zk connection. Calling close() twice will result in a panic.

func (*Connection) Create

func (c *Connection) Create(path string, node client.Node) error

Create places data at the node at the given path.

func (*Connection) CreateDir

func (c *Connection) CreateDir(path string) error

CreateDir creates an empty node at the given path.

func (*Connection) CreateEphemeral

func (c *Connection) CreateEphemeral(path string, node client.Node) (string, error)

func (*Connection) Delete

func (c *Connection) Delete(path string) error

Delete will delete all nodes at the given path or any subpath

func (*Connection) Exists

func (c *Connection) Exists(path string) (bool, error)

Exists checks if a node exists at the given path.

func (*Connection) Get

func (c *Connection) Get(path string, node client.Node) (err error)

Get returns the node at the given path.

func (*Connection) GetW

func (c *Connection) GetW(path string, node client.Node) (event <-chan client.Event, err error)

GetW gets the node at the given path and return a channel to watch for events on that node.

func (*Connection) ID

func (c *Connection) ID() int

ID returns the ID of the connection.

func (*Connection) NewLeader

func (c *Connection) NewLeader(path string, node client.Node) client.Leader

NewLeader returns a managed leader object at the given path bound to the current connection.

func (*Connection) NewLock

func (c *Connection) NewLock(path string) client.Lock

NewLock returns a managed lock object at the given path bound to the current connection.

func (*Connection) Set

func (c *Connection) Set(path string, node client.Node) error

Set serializes the given node and places it at the given path.

func (*Connection) SetID

func (c *Connection) SetID(id int)

SetID sets the ID of a connection.

func (*Connection) SetOnClose

func (c *Connection) SetOnClose(f func(int))

SetOnClose sets the callback f to be called when Close is called on c.

type DSN

type DSN struct {
	Servers []string
	Timeout time.Duration
}

DSN is a Zookeeper specific struct used for connections. It can be serialized.

func NewDSN

func NewDSN(servers []string, timeout time.Duration) DSN

NewDSN returns a new DSN object from servers and timeout.

func ParseDSN

func ParseDSN(dsn string) (val DSN, err error)

ParseDSN decodes a string (JSON) represnation of a DSN object.

func (DSN) String

func (dsn DSN) String() string

String creates a parsable (JSON) string represenation of this DSN.

type Driver

type Driver struct{}

Driver implements a Zookeeper based client.Driver interface

func (*Driver) GetConnection

func (driver *Driver) GetConnection(dsn, basePath string) (client.Connection, error)

GetConnection returns a Zookeeper connection given the dsn. The caller is responsible for closing the returned connection.

type Leader

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

Leader is an object to facilitate creating an election in zookeeper.

func (*Leader) Current

func (l *Leader) Current(node client.Node) (err error)

Current returns the currect elected leader and deserializes it in to node. It will return ErrNoLeaderFound if no leader has been elected.

func (*Leader) ReleaseLead

func (l *Leader) ReleaseLead() error

ReleaseLead release the current leader role. It will return ErrNotLocked if the current object is not locked.

func (*Leader) TakeLead

func (l *Leader) TakeLead() (echan <-chan client.Event, err error)

TakeLead attempts to aquire the leader role. When aquired it return a channel on the leader node so the caller can react to changes in zookeeper

type Lock

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

Lock creates a object to facilitate create a locking pattern in zookeeper.

func (*Lock) Lock

func (l *Lock) Lock() (err error)

Lock attempts to acquire the lock.

func (*Lock) Unlock

func (l *Lock) Unlock() error

Unlock attempts to release the lock.