helpers

Documentation

Overview

Package helpers contains a few utility classes to handle topo.Server objects, and transitions from one topo implementation to another.

Index

• func CopyKeyspaces(ctx context.Context, fromTS, toTS *topo.Server)
• func CopyShardReplications(ctx context.Context, fromTS, toTS *topo.Server)
• func CopyShards(ctx context.Context, fromTS, toTS *topo.Server)
• func CopyTablets(ctx context.Context, fromTS, toTS *topo.Server)
• func NewTee(primary, secondary *topo.Server, reverseLockOrder bool) (*topo.Server, error)
• type TeeConn
  • func (c *TeeConn) Close()
  • func (c *TeeConn) Create(ctx context.Context, filePath string, contents []byte) (topo.Version, error)
  • func (c *TeeConn) Delete(ctx context.Context, filePath string, version topo.Version) error
  • func (c *TeeConn) Get(ctx context.Context, filePath string) ([]byte, topo.Version, error)
  • func (c *TeeConn) ListDir(ctx context.Context, dirPath string, full bool) ([]topo.DirEntry, error)
  • func (c *TeeConn) Lock(ctx context.Context, dirPath, contents string) (topo.LockDescriptor, error)
  • func (c *TeeConn) NewMasterParticipation(name, id string) (topo.MasterParticipation, error)
  • func (c *TeeConn) Update(ctx context.Context, filePath string, contents []byte, version topo.Version) (topo.Version, error)
  • func (c *TeeConn) Watch(ctx context.Context, filePath string) (*topo.WatchData, <-chan *topo.WatchData, topo.CancelFunc)
• type TeeFactory
  • func (f *TeeFactory) Create(cell, serverAddr, root string) (topo.Conn, error)
  • func (f *TeeFactory) HasGlobalReadOnlyCell(serverAddr, root string) bool

Functions

func CopyKeyspaces

func CopyKeyspaces(ctx context.Context, fromTS, toTS *topo.Server)

CopyKeyspaces will create the keyspaces in the destination topo.

func CopyShardReplications

func CopyShardReplications(ctx context.Context, fromTS, toTS *topo.Server)

CopyShardReplications will create the ShardReplication objects in the destination topo.

func CopyShards

func CopyShards(ctx context.Context, fromTS, toTS *topo.Server)

CopyShards will create the shards in the destination topo.

func CopyTablets

func CopyTablets(ctx context.Context, fromTS, toTS *topo.Server)

CopyTablets will create the tablets in the destination topo.

func NewTee

func NewTee(primary, secondary *topo.Server, reverseLockOrder bool) (*topo.Server, error)

NewTee returns a new topo.Server object. It uses a TeeFactory.

Types

type TeeConn

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

TeeConn implements the topo.Conn interface.

func (*TeeConn) Close

func (c *TeeConn) Close()

Close is part of the topo.Conn interface.

func (*TeeConn) Create

func (c *TeeConn) Create(ctx context.Context, filePath string, contents []byte) (topo.Version, error)

Create is part of the topo.Conn interface.

func (*TeeConn) Delete

func (c *TeeConn) Delete(ctx context.Context, filePath string, version topo.Version) error

Delete is part of the topo.Conn interface.

func (*TeeConn) Get

func (c *TeeConn) Get(ctx context.Context, filePath string) ([]byte, topo.Version, error)

Get is part of the topo.Conn interface.

func (*TeeConn) ListDir

func (c *TeeConn) ListDir(ctx context.Context, dirPath string, full bool) ([]topo.DirEntry, error)

ListDir is part of the topo.Conn interface.

func (*TeeConn) Lock

func (c *TeeConn) Lock(ctx context.Context, dirPath, contents string) (topo.LockDescriptor, error)

Lock is part of the topo.Conn interface.

func (*TeeConn) NewMasterParticipation

func (c *TeeConn) NewMasterParticipation(name, id string) (topo.MasterParticipation, error)

NewMasterParticipation is part of the topo.Conn interface.

func (*TeeConn) Update

func (c *TeeConn) Update(ctx context.Context, filePath string, contents []byte, version topo.Version) (topo.Version, error)

Update is part of the topo.Conn interface.

func (*TeeConn) Watch

func (c *TeeConn) Watch(ctx context.Context, filePath string) (*topo.WatchData, <-chan *topo.WatchData, topo.CancelFunc)

Watch is part of the topo.Conn interface

type TeeFactory

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

TeeFactory is an implementation of topo.Factory that uses a primary underlying topo.Server for all changes, but also duplicates the changes to a secondary topo.Server. It also locks both topo servers when needed. It is meant to be used during transitions from one topo.Server to another.

• primary: we read everything from it, and write to it. We also create MasterParticipation from it.
• secondary: we write to it as well, but we usually don't fail.
• we lock primary/secondary if reverseLockOrder is False,

or secondary/primary if reverseLockOrder is True.

func (*TeeFactory) Create

func (f *TeeFactory) Create(cell, serverAddr, root string) (topo.Conn, error)

Create is part of the topo.Factory interface.

func (*TeeFactory) HasGlobalReadOnlyCell

func (f *TeeFactory) HasGlobalReadOnlyCell(serverAddr, root string) bool

HasGlobalReadOnlyCell is part of the topo.Factory interface.