Nuitka Package Configuration

Introduction

For packaging, and compatibility, or some Python packages need to have special considerations in Nuitka. Some will not work without certain data files, sometimes modules depend on other modules in a hidden way, and for standalone DLLs might have to be included, that are loaded dynamically and therefore also invisible.

Another are is compatibility hacks, and removing bloat from code or just making sure, you are not using an unsupported version or wrong options for a package.

To make it easier to deal with missing DLLs, implicit imports, data files, bloat etc. Nuitka has a system with Yaml files. These ship inside of it and are located under plugins/standard and are designed to be easily be extended.

The structure of the filename is always *nuitka-package.config.yml. The standard file includes all things that are not in the standard library (stdlib) of Python. In stdlib2 and stdlib3 there are entries for the standard library. In stdlib2 there are only those for modules that are no longer available in Python3.

If you want to use your own configuration, you can do so by passing the filename of your Yaml file via the --user-package-configuration-file=my.nuitka-package.config.yml option.

If it could be interesting for the other parts of the user base of Nuitka, please do a PR that adds it to the general files. In this way, not every user has to repeat what you just did, and we can collectively maintain it.

The YAML Configuration File

At the beginning of the file you will find the following lines, which you can ignore, they are basically only there to silence checkers about problems that are too hard to avoid.

# yamllint disable rule:line-length
# yamllint disable rule:indentation
# yamllint disable rule:comments-indentation
# too many spelling things, spell-checker: disable
---

An entry in the file look like this:

- module-name: 'pandas._libs'
  implicit-imports:
    - depends:
      - 'pandas._libs.tslibs.np_datetime'
      - 'pandas._libs.tslibs.nattype'
      - 'pandas._libs.tslibs.base'

The module-name value is the name of the affected module. We will show and explain to you everything the other things in detail later. But the key principle is that a declaration always references a module by name.

It is also important to know that you do not have to worry about formatting. We have programmed our own tool for this, which formats everything automatically. This is executed via bin\autoformat-nuitka-source and automatically when pushing with git if you install the git hook (see Developer Manual for that).

There is also a Yaml schema file to check your files against and that in Visual Code is automatically applied to the Yaml files and that then supports you with auto-completion in Visual Code. So actually doing the change in PR form can be easier than not.

Documentation

Data Files

data-files:
  dest_path: '.' # default, relative to package directory, normally not needed
  dirs:
    - 'dir1'

  patterns:
    - 'file1'
    - '*.dat'

  empty_dirs:
    - 'empty_dir'

  empty_dir_structures:
    - 'empty_dir_structure'

  when: 'win32'

If a module needs data files, you can get Nuitka to copy them into the output with the following features.

Features

dest_path: target directory
dirs: all directories that should be copied
patterns: all files that should be copied (filename can be a glob pattern)
empty_dirs: all empty directories that should be copied
empty_dir_structures: all empty directory structures that should be copied
when: when is documented in a separate section

Examples

Example 1

The most simple form just adds a data folder. The data files are in a folder and lives inside the package directory.

- module-name: 'customtkinter'
  data-files:
     dirs:
       - 'assets'

Note

A dest_path is very unlikely necessary. It defaults to the . relative path. It would have to be a strange package or some code modification on top, that would require data files to live in another spot in the standalone distribution.

Example 2

This example includes a complete folder with data files in a package.

- module-name: 'tkinterweb'
  data-files:
    dirs:
      - 'tkhtml'

Note

The example is actually an imperfect solution, since dependent on architecture, files can be omitted. We are going to address this in an update later.

Example 3

This example will make sure an empty folder is created relative to a package.

- module-name: 'Crypto.Util._raw_api'
  data-files:
    empty_dirs:
      - '.'

Note

The reason this is necessary is that some packages expect to have their directory as derived from __file__ to exist. But for compiled packages, unless there is extension packages or data files copied into them, these directories do not exist.

DLLs

dlls:
  - from_filenames:
      relative_path: 'dlls'
      prefixes:
        - 'dll1'
        - 'mydll*'

      suffixes:
        - 'pyd'

    dest_path: 'output_dir'
    when: 'win32'

  - by_code:
    setup_code: ''
    filename_code: ''
    dest_path: 'output_dir'
    when: 'linux'

If a module dynamically requires DLLs, i.e. there is not an extension module is not linked against them, they must be specified in this way.

Features

from_filenames
relative_path: directory where the DLLs can be found relative to the module
prefixes: all DLLs that should be copied (filename can be a glob pattern)
suffixes: can be used to force the file extension
by_code
setup_code: code needed to prepare the filename_code
filename_code: code that outputs a the DLL filename from installation
dest_path: target directory
when: when is documented in a separate section

The recommended way goes by filename. The by_code version is still in flux and depends on compile time importing code, making it vulernable to compile time issues in many ways.

Examples

Example 1

Very simple example, the normal case, include a DLL with a known prefix from its package directory.

- module-name: 'vosk'
  dlls:
    - from_filenames:
        prefixes:
          - 'libvosk'
Example 2

Another more complex example, in which the DLL lives in a subfolder, and is even architecture dependant.

- module-name: 'tkinterweb'

  dlls:
    - from_filenames:
        relative_path: 'tkhtml/Windows/32-bit'
        prefixes:
          - 'Tkhtml'
      when: 'win32 and arch_x86'
    - from_filenames:
        relative_path: 'tkhtml/Windows/64-bit'
        prefixes:
          - 'Tkhtml'
      when: 'win32 and arch_amd64'
Example 3

Yet another example with architecture dependent DLLs all in one package, that we do not want to include all, and in fact, must not include all at the same time. This one selected by platform suffixes for DLLs.

- module-name: 'tls_client.cffi'

dlls:
   - from_filenames:
      relative_path: 'dependencies'
      prefixes:
         - 'tls-client'
      suffixes:
         - 'dll'
      when: 'win32'
   - from_filenames:
      relative_path: 'dependencies'
      prefixes:
         - 'tls-client'
      suffixes:
         - 'so'
      when: 'linux'
   - from_filenames:
      relative_path: 'dependencies'
      prefixes:
         - 'tls-client'
      suffixes:
         - 'dylib'
      when: 'macos'

EXEs

To Nuitka, an “EXEs” are like DLLs. Basically only a DLL with the executable bit set. So, for a given selector, you can just add executable: yes with the default for a DLL configuration being executable: no.

Examples

dlls:
  - from_filenames:
      prefixes:
        - 'subprocess'
      executable: 'yes'
  - from_filenames:
      prefixes:
        - ''  # first match decides

Anti-Bloat

anti-bloat:
  - description: 'remove tests'
    context: ''
    module_code: 'from hello import world'
    replacements_plain: ''
    replacements_re: ''
    replacements: ''
    change_function:
       'get_extension': 'un-callable'

    append_result: ''
    append_plain: ''
    when: ''

If you want to replace code, for example to remove dependencies, you can do that here.

Note

For avoiding optional modules imports, see the no-auto-follow that is applicable in implict imports section.

Features

description: description of what this anti-bloat does
context:
module_code: replace the entire code of a module with it
replacements_plain: search an replace plain strings
replacements_re: search an replace regular expressions
replacements: search a plain string and replace with an expression result
change_function: replace the code of a function. un-callable removes the function
append_result: append the result of an expression to module code
append_plain: append plain text to the module code
when: when is documented in a separate section

Examples

coming soon

Implicit-Imports

implicit-imports:
  - depends:
     - 'ctypes'

    pre-import-code: ''
    post-import-code: ''
    when: 'version("package_name") >= (1, 2, 1)'

Features

depends: modules that are required by this module
no-auto-follow: list of modules not really required by this module
pre-import-code: code to execute before a module is imported
post-import-code: code to execute after a module is imported
when: when is documented in a separate section

Examples

In this example, environment variables needed to resolve the path of the Qt plugins and the fonts directory are used. This is only needed on Linux and on standalone, and here is how the standard configuration does it. And there there more mundane implicit requirements, that come from the package using an extension module and on the inside cv2.

- module-name: 'cv2'
    - depends:
        - 'cv2.cv2'
        - 'numpy'
        - 'numpy.core'
    - pre-import-code:
        - |
          import os
          os.environ['QT_QPA_PLATFORM_PLUGIN_PATH'] = os.path.join(os.path.dirname(__file__), 'qt/plugins')
          os.environ['QT_QPA_FONTDIR'] = os.path.join(os.path.dirname(__file__), 'qt/fonts')
      when: 'linux and standalone'

For the no-auto-follow this shows how to not follow to a module, even with --follow-imports being given just because of this module doing an import. If another one does the import, it will be followed into still, but this particular modules not not cause it. The message given is shown when that happens. If if is ignore, nothing will be displayed.

In this concrete example, tdqm would register with pandas methods if possible, but handles it not being found gracefully. No need to include it just to do that, if pandas is otherwise unused.

- module-name: 'tqdm.std'
  anti-bloat:
    - no-auto-follow:
        'pandas': 'ignore'

Options

options:
  checks:
    - description: 'fix crash'
      console: 'yes'
      macos_bundle: 'yes'
      macos_bundle_as_onefile: 'no'
      support_info: 'warning'
      when: 'macos'

If a module requires specific options, you can specify them here, to make sure the user is informed of them.

Features

description: description of what this does
console: whether the console should be enabled. Choose between yes, no, recommend
macos_bundle: Choose between yes, no, recommend
macos_bundle_as_onefile: Choose between yes, no
support_info: Choose between info, warning, error
when: when is documented in a separate section

Examples

On macOS, the popular wx toolkit will not work unless the application is a GUI program. The result is a crash without any information to the user. It also will not work unless it’s in a macOS bundle. So this configuration will make sure to warn or error out in case these modes are not enabled.

- module-name: 'wx'
  options:
    checks:
      - description: 'wx will crash in console mode during startup'
        console: 'yes'
        when: 'macos'
      - description: 'wx requires program to be in bundle form'
        macos_bundle: 'yes'
        when: 'macos'

Import-Hacks

import-hacks:
  - package-paths:
     - 'vtkmodules'

    package-dirs:
      - 'win32comext'

    find-dlls-near-module:
      - 'shiboken2'

    when: "True"

Features

package-paths:
package-dirs:
find-dlls-near-module:
global-sys-path:: for modules that manipulate sys.path

Examples

The module tkinterweb contains the following code, that Nuitka doesn’t yet understand well enough at compile time.

sys.path.append(os.path.dirname(os.path.realpath(__file__)))

What this does is to add the package directory, such that Python files in the package directory are visible as global imports. To Nuitka these will not be resolvable, unless we help it.

- module-name: 'tkinterweb'
  import-hacks:
    - global-sys-path:
        # This package forces itself into "sys.path" and expects absolute
        # imports to be available.
        - ''

This adds the relative path '' during compile time to the import resolution, making it work. This makes the sys.path modification visible to Nuitka. Suffice to say that this is very unusual, thus it’s in the import hacks category.

Variables

It is possible to use compile time package information in an expression like the e.g. when clauses, but also for some other values. They are then accessed via the get_variable function and reporting and caching traces their usage.

Note

Where they are not currently working, we might have to add support for that.

variables:
  setup_code: 'import whatever'
  declarations:
    'variable1_name': 'whatever.something()'
    'variable2_name': 'whatever.something2()'

Constants

constants:
  - declarations:
      'suffix': '-Windows'
    when: "win32"
  - declarations:
      'suffix': '-Linux'
    when: "linux"
  - declarations:
      'suffix': '-MacOS'
    when: "macos"

It is possible to use compile time package information in an expression like the e.g. when clauses, but also for some other values that allow using an expression, e.g. when constructing paths. They are then accessed via the get_variable function and reporting and caching traces their usage.

They are most useful to avoid repeated usage of OS specific values without making using configuration repeated with different when clauses, as those and then only there for defined constants.

We do not yet have examples, we intend to use this to cleanup a few of the configurations that we already have or use it in the future.

Expression

Example of an expression:

macos and python3_or_higher

These variables are available for quick tests. The idea being that actual code is never going to be necessary in these expressions.

OS Indications

To check what OS is selected, we got these.

macos: True if OS is MacOS
win32: True if OS is Windows
linux: True if OS is Linux

Compilation modes

standalone: True if standalone mode is activated with --standalone or --onefile
module_mode: True if module mode is activated with --module
deployment: True if deployment mode is activated with --deployment

Note

For non-deployment changes, these can be annotated with the deployment annotation. We need to be careful with general doing changes in that way, because it makes testing harder, and changes e.g. to make numpy not hide bugs of our packaging of its DLLs behind a misleading error, are usually very good for deployment too.

Python Flavors

To check the Python flavor, we got these.

anaconda: True if Anaconda Python used, but see is_conda_package below
debian_python: True if Debian Python used

More could be added, but these are the trouble makers that sometimes need special handling due to them modifying PyPI packages for themselves to use.

Package Versions

To check the version of packages and distributions, we got these.

version: tuple of int get version of distribution
get_dist_name: str resolve package name to distribution

For packages, that have multiple distribution names potentially, it’s best to use it like this version(get_dist_name("cv2")) < (4,6) as often this can be one of many different names.

Note

In many cases, package name and distribution name align, but that is not always the case.

Python Versions

For limiting to certain Python versions, we got Python3 indicators and more Python version specific ones:

before_python3: True if Python 2 used
python3_or_higher: True if Python 3 used
python[major][minor]_or_higher: e.g. python310_or_higher
before_python[major][minor]: e.g. before_python310

Anti-Bloat

The Anti-Bloat plugin provides you with additional variables from command line choices. These are mainly intended for the anti-bloat section, but work everywhere now.

use_setuptools: True if --noinclude-setuptools-mode is not set to nofollow or error
use_pytest: True if --noinclude-pytest-mode is not set to nofollow or error
use_unittest: True if --noinclude-unittest-mode is not set to nofollow or error
use_ipython: True if --noinclude-IPython-mode is not set to nofollow or error
use_dask: True if --noinclude-dask-mode is not set to nofollow or error

All these are bools as well.

Package Versions

To check the version of a package there is the version function, which you simply pass the name to and you then get the version as a tuple. An example:

version("rich") is not None and version("rich") >= (10, 2, 2)

It returns None if the package isn’t installed, sometimes this need handling, e.g. in the configuration of another package.s

Due to differences in DLL and data file layout, conda packages (from Anaconda) will be different. But running anaconda is not sufficient, in case the package from from pip install rather than conda install, so this allows to make a difference for this.

It returns a boolean value. No need to check for anaconda, that is implied of course, and probably should never be used, but this instead.

is_conda_package("shapely")

Python Flags

Also, the global (or module local in the future) compilation modules, like no_asserts, no_docstrings, and no_annotations are available. These are for use in anti-bloat where packages sometimes will not work unless helped somewhat.

Experimental Settings

For development, there is a function experimental that you can use to check for the presence of flags given on the command line. So you can use that to toggle a change on or off until you are happy with it, or attach it to an incomplete feature of Nuitka.

# bool, true if --experimental=some-flag-name given
experimental('some-flag-name')

Variable/Constant Values

For variables/constants to be used, they need to be defined within the package configuration as constants or variables. They then become accessible, but variables are only evaluated if they are actually used. That means, if e.g. the when clause causes a variable to be unused, it’s never evaluated.

Note

Where an expression is not currently working, we might have to add support for that, this is an ongoing effort.

Examples

The most simple form just picks up information from a package, in this instance, we ask the package about the backend it would use with the current configuration and all, and force the decision to be that by changing the very same function to be compiled into producing just that value without further investigation.

This is a simple solution to a common problem, namely to persist such decisions from the original compiling environment to the target environment.

Example 1
- module-name: 'toga.platform'
  variables:
    setup_code: 'import toga.platform'
    declarations:
      'toga_backend_module_name': 'toga.platform.get_platform_factory(). __name__'
  anti-bloat:
    - change_function:
        'get_platform_factory': "'importlib.import_module(%r)' % get_variable('toga_backend_module_name')"

when

In the when part an expression is given and if it matches, the entry it is attached to is applied, otherwise not. This expression is a normal string evaluated by Python’s eval function. Nuitka provides variables in the context for this.

Where else to look

There is a post series under the tag package_config found https://nuitka.net/blog/tag/package_config.html that explains some things in more detail and is going to cover this and expand it for some time.

Then of course, there is also the current package configuration file, located at https://github.com/Nuitka/Nuitka/blob/develop/nuitka/plugins/standard/standard.nuitka-package.config.yml that is full of examples.