core.displaypub

Module: core.displaypub

Inheritance diagram for IPython.core.displaypub:

An interface for publishing rich data to frontends.

There are two components of the display system:

• Display formatters, which take a Python object and compute the representation of the object in various formats (text, HTML, SVg, etc.).
• The display publisher that is used to send the representation data to the various frontends.

This module defines the logic display publishing. The display publisher uses the display_data message type that is defined in the IPython messaging spec.

Authors:

• Brian Granger

DisplayPublisher

class IPython.core.displaypub.DisplayPublisher(**kwargs)

Bases: IPython.config.configurable.Configurable

A traited class that publishes display data to frontends.

Instances of this class are created by the main IPython object and should be accessed there.

__init__(**kwargs)

Create a configurable given a config config.

Parameters :

config : Config

If this is empty, default values are used. If config is a Config instance, it will be used to configure the instance.

Notes

Subclasses of Configurable must call the __init__() method of Configurable before doing anything else and using super():

class MyConfigurable(Configurable):
    def __init__(self, config=None):
        super(MyConfigurable, self).__init__(config)
        # Then any other code you need to finish initialization.

This ensures that instances will be configured properly.

classmethod class_config_section()

Get the config class config section

classmethod class_get_help()

Get the help string for this class in ReST format.

classmethod class_get_trait_help(trait)

Get the help string for a single trait.

classmethod class_print_help()

Get the help string for a single trait and print it.

classmethod class_trait_names(**metadata)

Get a list of all the names of this classes traits.

This method is just like the trait_names() method, but is unbound.

classmethod class_traits(**metadata)

Get a list of all the traits of this class.

This method is just like the traits() method, but is unbound.

The TraitTypes returned don’t know anything about the values that the various HasTrait’s instances are holding.

This follows the same algorithm as traits does and does not allow for any simple way of specifying merely that a metadata name exists, but has any value. This is because get_metadata returns None if a metadata key doesn’t exist.

config

A trait whose value must be an instance of a specified class.

The value can also be an instance of a subclass of the specified class.

created = None

on_trait_change(handler, name=None, remove=False)

Setup a handler to be called when a trait changes.

This is used to setup dynamic notifications of trait changes.

Static handlers can be created by creating methods on a HasTraits subclass with the naming convention ‘_[traitname]_changed’. Thus, to create static handler for the trait ‘a’, create the method _a_changed(self, name, old, new) (fewer arguments can be used, see below).

Parameters :

handler : callable

A callable that is called when a trait changes. Its signature can be handler(), handler(name), handler(name, new) or handler(name, old, new).

name : list, str, None

If None, the handler will apply to all traits. If a list of str, handler will apply to all names in the list. If a str, the handler will apply just to that name.

remove : bool

If False (the default), then install the handler. If True then unintall it.

publish(source, data, metadata=None)

Publish data and metadata to all frontends.

See the display_data message in the messaging documentation for more details about this message type.

The following MIME types are currently implemented:

• text/plain
• text/html
• text/latex
• application/json
• image/png
• immage/svg+xml

Parameters :

source : str

A string that give the function or method that created the data, such as ‘IPython.core.page’.

data : dict

A dictionary having keys that are valid MIME types (like ‘text/plain’ or ‘image/svg+xml’) and values that are the data for that MIME type. The data itself must be a JSON’able data structure. Minimally all data should have the ‘text/plain’ data, which can be displayed by all frontends. If more than the plain text is given, it is up to the frontend to decide which representation to use.

metadata : dict

A dictionary for metadata related to the data. This can contain arbitrary key, value pairs that frontends can use to interpret the data.

trait_metadata(traitname, key)

Get metadata values for trait by key.

trait_names(**metadata)

Get a list of all the names of this classes traits.

traits(**metadata)

Get a list of all the traits of this class.

The TraitTypes returned don’t know anything about the values that the various HasTrait’s instances are holding.

This follows the same algorithm as traits does and does not allow for any simple way of specifying merely that a metadata name exists, but has any value. This is because get_metadata returns None if a metadata key doesn’t exist.

IPython.core.displaypub.publish_display_data(self, source, data, metadata=None)

Publish data and metadata to all frontends.

See the display_data message in the messaging documentation for more details about this message type.

The following MIME types are currently implemented:

• text/plain
• text/html
• text/latex
• application/json
• image/png
• immage/svg+xml

Parameters :

source : str

A string that give the function or method that created the data, such as ‘IPython.core.page’.

data : dict

A dictionary having keys that are valid MIME types (like ‘text/plain’ or ‘image/svg+xml’) and values that are the data for that MIME type. The data itself must be a JSON’able data structure. Minimally all data should have the ‘text/plain’ data, which can be displayed by all frontends. If more than the plain text is given, it is up to the frontend to decide which representation to use.

metadata : dict

A dictionary for metadata related to the data. This can contain arbitrary key, value pairs that frontends can use to interpret the data.