ait.core.server.plugin module

class ait.core.server.plugin.Plugin(inputs, outputs, zmq_args=None, **kwargs)

Bases: ait.core.server.client.ZMQInputClient

This is the parent class for all plugins. All plugins must implement their own process method which is called when a message is received.

__init__(inputs, outputs, zmq_args=None, **kwargs)

Constructor

Params:

inputs: names of inbound streams plugin receives data from outputs: names of outbound streams plugin sends its data to zmq_args: dict containing the follow keys:

zmq_context zmq_proxy_xsub_url zmq_proxy_xpub_url

Defaults to empty dict. Default values assigned during instantiation of parent class.

**kwargs: (optional) Dependent on requirements of child class.

static create_plugin(plugin_config)

Static utility method that instantiates extensions of the Plugin class

Params:

plugin_config: Plugin configuration associated with Plugin instance

Returns:

Plugin - New Plugin extension

Raises:

ValueError: if any of the required config values are missing

or plugin class can not be imported/loaded

process(input_data, topic=None)

Not implemented by base Plugin class. This process method must be implemented by any custom plugin class that inherits from this base Plugin.

Params:

input_data: Message received from any of the plugin’s input streams. topic: Name of stream that message was received from.

class ait.core.server.plugin.PluginConfig(name, inputs=None, outputs=None, zmq_args=None, kwargs=None)

Bases: object

Data-structure for plugin information. Would be useful if we allow multiple plugins to run in a common child-process

__init__(name, inputs=None, outputs=None, zmq_args=None, kwargs=None)

Constructor

Params:

name: Name of the Plugin class (required) inputs: names of inbound streams plugin receives data from outputs: names of outbound streams plugin sends its data to zmq_args: dict containing the follow keys:

zmq_context zmq_proxy_xsub_url zmq_proxy_xpub_url

Defaults to empty dict. Default values assigned during instantiation of parent class.

**kwargs: (optional) Dependent on requirements of child class.

static build_from_ait_config(ait_plugin_config, zmq_args=None)

Static method that extracts information from AIT Plugin configuration and returns a newly instantiated PluginConfig object. Any required configuration that is missing will result in error.

Params:

ait_plugin_config: AIT configuration section of a plugin zmq_args: ZMQ settings

Returns:

PluginConfig - New PluginConfig built from config

Raises:

AitConfigMissing: if any of the required config values are missing

get_zmq_context()

Convenience method that gets value of the ZMQ context

Returns: ZMQ Context, possibly None

set_zmq_context(context)

Convenience method that gets value of the ZMQ context

Params:

context: ZeroMQ Context, can be None

short_name

Returns the classname portion of the fullname Returns: Class name of plugin type

class ait.core.server.plugin.PluginType

Bases: enum.Enum

Enumeration for Plugin type: standard plugin (greenlet) or process-based

PROCESS = 2

STANDARD = 1

value_of = <bound method PluginType.value_of of <enum 'PluginType'>>