generalimport 0.3

Handle all your optional dependencies with a single call!

generalimport

Handle all your optional dependencies with a single call!

Table of Contents

generalimport
├─ Dependency Diagram for ManderaGeneral
├─ Installation showing dependencies
├─ Information
├─ Examples
│  ├─ Minimal Example
│  ├─ Tests Showcase
│  ├─ Recommended Setup
│  └─ How It Works
├─ Attributes
└─ Contributions

Dependency Diagram for ManderaGeneral

flowchart LR
2([file]) --> 4([packager])
1([library]) --> 2([file])
0([import]) --> 2([file])
1([library]) --> 3([vector])
1([library]) --> 4([packager])
0([import]) --> 1([library])
click 0 "https://github.com/ManderaGeneral/generalimport"
click 1 "https://github.com/ManderaGeneral/generallibrary"
click 2 "https://github.com/ManderaGeneral/generalfile"
click 3 "https://github.com/ManderaGeneral/generalvector"
click 4 "https://github.com/ManderaGeneral/generalpackager"
style 0 fill:#482

Installation showing dependencies

pip install	generalimport
No dependencies	✔️

Information

Package	Ver	Latest Release	Python	Platform	Cover
generalimport	0.3	2022-10-19 16:23 CEST	3.8, 3.9, 3.10	Windows, Ubuntu	98.4 %

Examples

Minimal Example

Call generalimport before importing any optional dependencies.

from generalimport import generalimport
generalimport("notinstalled")

from notinstalled import missing_func  # No error

missing_func()  # Error occurs here

MissingOptionalDependency: Optional dependency 'notinstalled' was used but it isn't installed.

Imports fail when they are used, not imported.

This means you don't need to keep checking if the package is installed before importing it. Simply import your optional package and use it like you would any package and let it fail wherever it fails, with a nice error message.

Tests Showcase

The beauty of this package is that the error raised isn't just any exception. It has two base classes: unittest.case.SkipTest and _pytest.outcomes.Skipped (If available).

This means that if a test method uses an uninstalled optional package then that test is automatically skipped. This means no more manual skip decorators for optional dependencies!

from generalimport import generalimport
generalimport("optional_uninstalled_package")

from optional_uninstalled_package import missing_func

from unittest import TestCase

class MyTest(TestCase):
    def test_missing_func(self):
        self.assertEqual(3, missing_func(1, 2))

Ran 1 test in 0.002s

OK (skipped=1)

Skipped: Optional dependency 'optional_uninstalled_package' was used but it isn't installed.

Recommended Setup

Put this in your __init__.py file to affect all imports inside the folder __init__.py resides in.

from generalimport import generalimport
generalimport("your", "optional", "dependencies")

generalimport("*") makes it handle all names (If missing of course)

:warning: generalimport("*")._scope = None disables the scope

• Makes it handle missing imports anywhere
• For example it will override pandas internal custom optional dependency handling

How It Works

• When generalimport is instantiated it creates a new importer for sys.meta_path.
• This importer will return 'fake' modules for matching names and scope.
• The scope ensures only your own imports are faked.
• The fake module will recursively return itself when asked for an attribute.
• When used in any way (__call__, __add__, __str__ etc) it raises generalimport.MissingOptionalDependency.
• This exception has the 'skip-exceptions' from unittest and pytest as bases, which means that tests will automatically be skipped.

Attributes

Module: generalimport
├─ Class: FakeModule (Untested)
│  └─ Method: error_func (Untested)
├─ Class: GeneralImporter
│  ├─ Method: catch
│  ├─ Method: create_module (Untested)
│  ├─ Method: exec_module (Untested)
│  └─ Method: find_spec (Untested)
├─ Class: ImportCatcher (Untested)
│  └─ Method: handle (Untested)
├─ Class: MissingOptionalDependency
├─ Function: fake_module_check
├─ Function: generalimport
├─ Function: get_importer
├─ Function: get_installed_modules_names
├─ Function: get_spec (Untested)
├─ Function: import_module
├─ Function: module_is_installed
├─ Function: module_is_namespace (Untested)
├─ Function: module_name_is_namespace
├─ Function: reset_generalimport
└─ Function: spec_is_namespace (Untested)

Contributions

Issue-creation, discussions and pull requests are most welcome!

^{Generated 2022-10-19 16:23 CEST for commit b278ff6.}