Class Channel

Create a new Channel.

In user code, this Channel constructor will not typically be called
manually since there are functions for creating channels for each specific
type with a more customized set of arguments to pass.

Args:
  type: str, The type of delivery mechanism used by this channel. For
    example, 'web_hook'.
  id: str, A UUID for the channel.
  token: str, An arbitrary string associated with the channel that
    is delivered to the target address with each event delivered
    over this channel.
  address: str,  The address of the receiving entity where events are
    delivered. Specific to the channel type.
  expiration: int, The time, in milliseconds from the epoch, when this
    channel will expire.
  params: dict, A dictionary of string to string, with additional parameters
    controlling delivery channel behavior.
  resource_id: str, An opaque id that identifies the resource that is
    being watched. Stable across different API versions.
  resource_uri: str, The canonicalized ID of the watched resource.

Decorators:

• @util.positional(5)

Overrides: object.__init__

Build a body from the Channel.

Constructs a dictionary that's appropriate for passing into watch()
methods as the value of body argument.

Returns:
  A dictionary representation of the channel.

Update a channel with information from the response of watch().

When a request is sent to watch() a resource, the response returned
from the watch() request is a dictionary with updated channel information,
such as the resource_id, which is needed when stopping a subscription.

Args:
  resp: dict, The response from a watch() method.