Hook Configuration Options

As of version 4.4, PyInstaller implements a mechanism for passing configuration options to the hooks. At the time of writing, this feature is supported only in .spec files and has no command-line interface equivalent.

The hook configuration options consist of a dictionary that is passed to the Analysis object via the hooksconfig argument. The keys of the dictionary represent hook identifiers while the values are dictionaries of hook-specific keys and values that correspond to hook settings:

a = Analysis(
    ["program.py"],
    ...,
    hooksconfig={
        "some_hook_id": {
            "foo": ["entry1", "entry2"],
            "bar": 42,
            "enable_x": True,
        },
        "another_hook_id": {
            "baz": "value",
        },
    },
    ...,
)

Supported hooks and options

This section lists hooks that implement support for configuration options. For each hook (or group of hooks), we provide the hook identifier and the list of supported options.

GObject introspection (gi) hooks

The options passed under gi hook identifier control the collection of GLib/Gtk resources (themes, icons, translations) in various hooks related to GObject introspection (i.e., hook-gi.*).

They are especially useful when freezing Gtk3-based applications on linux, as they allow one to limit the amount of themes and icons collected from the system /usr/share directory.

Hook identifier: gi

Options

  • languages [list of strings]: list of locales (e.g., ˙en_US˙) for which translations should be collected. By default, gi hooks collect all available translations.

  • icons [list of strings]: list of icon themes (e.g., Adwaita) that should be collected. By default, gi hooks collect all available icon themes.

  • themes [list of strings]: list of Gtk themes (e.g., Adwaita) that should be collected. By default, gi hooks collect all available icon themes.

  • module-versions [dict of version strings]: versions of gi modules to use. For example, a key of ‘GtkSource’ and value to ‘4’ will use gtksourceview4.

Example

Collect only Adwaita theme and icons, limit the collected translations to British English and Simplified Chinese, and use version 3.0 of Gtk and version 4 of GtkSource:

a = Analysis(
    ["my-gtk-app.py"],
    ...,
    hooksconfig={
        "gi": {
            "icons": ["Adwaita"],
            "themes": ["Adwaita"],
            "languages": ["en_GB", "zh_CN"],
            "module-versions": {
                "Gtk": "3.0",
                "GtkSource": "4",
            },
        },
    },
    ...,
)

Note

Currently only the module-versions configuration is available for GtkSource.

Matplotlib hooks

The hooks for matplotlib package allow user to control the backend collection behavior via backends option under the matplotlib identifier, as described below.

Hook identifier: matplotlib

Options

  • backends [string or list of strings]: backend selection method or name(s) of backend(s) to collect. Valid string values: 'auto', 'all', or a human-readable backend name (e.g., 'TkAgg'). To specify multiple backends to be collected, use a list of strings (e.g., ['TkAgg', 'Qt5Agg']).

Backend selection process

If backends option is set to 'auto' (or not specified), the hook performs auto-detection of used backends, by scanning the code for matplotlib.use() function calls with literal arguments. For example, matplotlib.use('TkAgg') being used in the code results in the TkAgg backend being collected. If no such calls are found, the default backend is determined as the first importable GUI-based backend, using the same priority list as internally used by the matplotlib.get_backend() and matplotlib.pyplot.switch_backend() functions: ['MacOSX', 'Qt5Agg', 'Gtk3Agg', 'TkAgg', 'WxAgg']. If no GUI-based backend is importable, the headless 'Agg' is collected instead.

Note

Due to limitations of the bytecode-scanning approach, only specific forms of matplotlib.use() invocation can be automatically detected. The backend must be specified as string literal (as opposed to being passed via a variable). The second optional argument, force, can also be specified, but it must also be a literal and must not be specified as a keyword argument:

import matplotlib

matplotlib.use('TkAgg')  # detected
matplotlib.use('TkAgg', False)  # detected

backend = 'TkAgg'
matplotlib.use(backend)  # not detected

matplotlib.use('TkAgg', force=False)  # not detected

In addition to matplotlib module name, its common alias, mpl is also recongized:

import matplotlib as mpl
mpl.use('TkAgg')  # detected

Importing the function from the module should also work:

from matplotlib import use
use('TkAgg')  # detected

If backends option is set to 'all', all (importable) backends are selected, which corresponds to the behavior of PyInstaller 4.x and earlier. The list of importable backends depends on the packages installed in the environment; for example, the Qt5Agg backend becomes importable if either the PyQt5 or the PySide2 package is installed.

Otherwise, the value of the backends option is treated as a backend name (if it is a string) or a list of backend names (if it is a list). In the case of user-provided backend names, no additional validation is performed; the backends are collected regardless of whether they are importable or not.

Example

a = Analysis(
    ["my-matplotlib-app.py"],
    ...,
    hooksconfig={
        "matplotlib": {
            "backends": "auto",  # auto-detect; the default behavior
            # "backends": "all",  # collect all backends
            # "backends": "TkAgg",  # collect a specific backend
            # "backends": ["TkAgg", "Qt5Agg"],  # collect multiple backends
        },
    },
    ...,
)

Note

The Qt5Agg backend conditionally imports both the PyQt5 and the PySide2 package. Therefore, if both are installed in your environment, PyInstaller will end up collecting both. In addition to increasing the frozen application’s size, this might also cause conflicts between the collected versions of the shared libraries. To prevent that, use the --exclude-module option to exclude one of the two packages (i.e., --exclude-module PyQt5 or --exclude-module PySide2).

Adding an option to the hook

Implementing support for hook options requires access to hook_api object, which is available only when hook implements the hook(hook_api) function (as described here).

The value of a hook’s configuration option can be obtained using the get_hook_config() function:

# hook-mypackage.py
from PyInstaller.utils.hooks import get_hook_config

# Processing unrelated to hook options, using global hook values
binaries, datas, hiddenimports = ...

# Collect extra data
def hook(hook_api):
    # Boolean option 'collect_extra_data'
    if get_hook_config(hook_api, 'mypackage', 'collect_extra_data'):
        extra_datas = ...  # Collect extra data
        hook_api.add_datas(extra_datas)

After implementing option handling in the hook, please add a section documenting it under Supported hooks and options, to inform the users of the option’s availability and the meaning of its value(s).

The above hook example allows the user to toggle the collection of extra data from mypackage by setting the corresponding option in their .spec file:

a = Analysis(
    ["program-using-mypackage.py"],
    ...,
    hooksconfig={
        "mypackage": {
            "collect_extra_data": True,
        },
    },
    ...,
)