event

Documentation

Overview

Package event enables access to a channel events on a Fabric network. Event client receives events such as block, filtered block, chaincode, and transaction status events.

Basic Flow:
1) Prepare channel client context
2) Create event client
3) Register for events
4) Process events (or timeout)
5) Unregister

Index

• type Client
  • func New(channelProvider context.ChannelProvider, opts ...ClientOption) (*Client, error)
  • func (c *Client) RegisterBlockEvent(filter ...fab.BlockFilter) (fab.Registration, <-chan *fab.BlockEvent, error)
  • func (c *Client) RegisterChaincodeEvent(ccID, eventFilter string) (fab.Registration, <-chan *fab.CCEvent, error)
  • func (c *Client) RegisterFilteredBlockEvent() (fab.Registration, <-chan *fab.FilteredBlockEvent, error)
  • func (c *Client) RegisterTxStatusEvent(txID string) (fab.Registration, <-chan *fab.TxStatusEvent, error)
  • func (c *Client) Unregister(reg fab.Registration)
• type ClientOption
  • func WithBlockEvents() ClientOption
  • func WithBlockNum(from uint64) ClientOption
  • func WithSeekType(seek seek.Type) ClientOption

Types

type Client

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

Client enables access to a channel events on a Fabric network.

func New

func New(channelProvider context.ChannelProvider, opts ...ClientOption) (*Client, error)

New returns a Client instance. Client receives events such as block, filtered block, chaincode, and transaction status events.

func (*Client) RegisterBlockEvent

func (c *Client) RegisterBlockEvent(filter ...fab.BlockFilter) (fab.Registration, <-chan *fab.BlockEvent, error)

RegisterBlockEvent registers for block events. If the caller does not have permission to register for block events then an error is returned. Unregister must be called when the registration is no longer needed.

Parameters:
filter is an optional filter that filters out unwanted events. (Note: Only one filter may be specified.)

Returns:
the registration and a channel that is used to receive events. The channel is closed when Unregister is called.

func (*Client) RegisterChaincodeEvent

func (c *Client) RegisterChaincodeEvent(ccID, eventFilter string) (fab.Registration, <-chan *fab.CCEvent, error)

RegisterChaincodeEvent registers for chaincode events. Unregister must be called when the registration is no longer needed.

Parameters:
ccID is the chaincode ID for which events are to be received
eventFilter is the chaincode event filter (regular expression) for which events are to be received

Returns:
the registration and a channel that is used to receive events. The channel is closed when Unregister is called.

func (*Client) RegisterFilteredBlockEvent

func (c *Client) RegisterFilteredBlockEvent() (fab.Registration, <-chan *fab.FilteredBlockEvent, error)

RegisterFilteredBlockEvent registers for filtered block events. Unregister must be called when the registration is no longer needed.

Returns:
the registration and a channel that is used to receive events. The channel is closed when Unregister is called.

func (*Client) RegisterTxStatusEvent

func (c *Client) RegisterTxStatusEvent(txID string) (fab.Registration, <-chan *fab.TxStatusEvent, error)

RegisterTxStatusEvent registers for transaction status events. Unregister must be called when the registration is no longer needed.

Parameters:
txID is the transaction ID for which events are to be received

Returns:
the registration and a channel that is used to receive events. The channel is closed when Unregister is called.

func (*Client) Unregister

func (c *Client) Unregister(reg fab.Registration)

Unregister removes the given registration and closes the event channel.

Parameters:
reg is the registration handle that was returned from one of the Register functions

type ClientOption

type ClientOption func(*Client) error

ClientOption describes a functional parameter for the New constructor

func WithBlockEvents

func WithBlockEvents() ClientOption

WithBlockEvents indicates that block events are to be received. Note that the caller must have sufficient privileges for this option.

func WithBlockNum

func WithBlockNum(from uint64) ClientOption

WithBlockNum indicates the block number from which events are to be received. Only deliverclient supports this

func WithSeekType

func WithSeekType(seek seek.Type) ClientOption

WithSeekType indicates the type of seek desired - newest, oldest or from given block Only deliverclient supports this