com.google.appengine.api.channel
Interface ChannelService

public interface ChannelService

ChannelService allows you to manage manage two-way connections with clients.

Method Summary

java.lang.String	createChannel(java.lang.String clientId) Creates a channel associated with the provided clientId and returns a token that is valid for the default amount of time (2 hours)
java.lang.String	createChannel(java.lang.String clientId, int durationMinutes) Creates a channel associated with the provided clientId and returns a token that is valid for the specified period of time.
ChannelMessage	parseMessage(HttpServletRequest request) Parse the incoming message in request.
ChannelPresence	parsePresence(HttpServletRequest request) Parse the incoming presence in request.
void	sendMessage(ChannelMessage message) Sends a ChannelMessage to the client.

Method Detail

createChannel

java.lang.String createChannel(java.lang.String clientId)

Creates a channel associated with the provided clientId and returns a token that is valid for the default amount of time (2 hours)

Parameters:

clientId - A string uniquely identifying the client that will use the returned token to connect to this channel. This string must be fewer than 64 bytes when encoded to UTF-8.

Returns:

the token the client will use to connect to this channel.

Throws:

ChannelFailureException - if there is an error encountered while communicating with the channel service.

createChannel

java.lang.String createChannel(java.lang.String clientId,
                               int durationMinutes)

Creates a channel associated with the provided clientId and returns a token that is valid for the specified period of time.

Parameters:

clientId - A string uniquely identifying the client that will use the returned token to connect to this channel. This string must be fewer than 64 bytes when encoded to UTF-8.

durationMinutes - the amount of time for which the returned token will be valid, in minutes. Must be greater than zero and less than 24 * 60.

Returns:

the token the client will use to connect to this channel.

Throws:

ChannelFailureException - if there is an error encountered while communicating with the channel service.

sendMessage

void sendMessage(ChannelMessage message)

Sends a ChannelMessage to the client.

Parameters:

message - the message to be sent to all connected clients.

Throws:

ChannelFailureException - if there is an error encountered while communicating with the channel service.

parseMessage

ChannelMessage parseMessage(HttpServletRequest request)

Parse the incoming message in request. This method should only be called within a channel webhook.

Parameters:

request - the source HTTP request.

Returns:

the incoming ChannelMessage.

Throws:

java.lang.IllegalStateException - if the required HTTP parameters are not present.

parsePresence

ChannelPresence parsePresence(HttpServletRequest request)
                              throws java.io.IOException

Parse the incoming presence in request. This method should only be called within a channel presence request handler.

Parameters:

request - the source HTTP request.

Returns:

the incoming ChannelPresence.

Throws:

java.io.IOException - if the MIME body isn't parseable.

java.lang.IllegalArgumentException - if the HTTP request doesn't conform to expectations.