hammurabi.preconditions package

Submodules

hammurabi.preconditions.attributes module

This module contains the definition of Preconditions which are related to attributes of a file or directory.

class hammurabi.preconditions.attributes.HasMode(path: pathlib.Path, mode: int, **kwargs)

Bases: hammurabi.preconditions.base.Precondition

Check if the given file or directory has the required permissions/mode.

You can read more about the available modes at https://docs.python.org/3/library/stat.html.

Example usage:

>>> import stat
>>> from pathlib import Path
>>> from hammurabi import Law, Pillar, Renamed, HasMode
>>>
>>> example_law = Law(
>>>     name="Name of the law",
>>>     description="Well detailed description what this law does.",
>>>     rules=(
>>>         Renamed(
>>>             name="Rename pyproject.toml if owned by gabor",
>>>             path=Path("./pyproject.toml"),
>>>             new_name="gabor-pyproject.toml"
>>>             preconditions=[
>>>                 HasMode(path=Path("scripts/run_unittests.sh"), mode=stat.S_IXOTH)
>>>             ]
>>>         ),
>>>     )
>>> )
>>>
>>> pillar = Pillar()
>>> pillar.register(example_law)

Parameters

• path (Path) – Input file’s path

• mode (str) – The desired mode to check

made_changes

name

param

task() → bool

Check if the given mode is set on the file or directory.

Returns

Returns True if the desired mode is set

Return type

bool

class hammurabi.preconditions.attributes.HasNoMode(path: pathlib.Path, mode: int, **kwargs)

Bases: hammurabi.preconditions.attributes.HasMode

Opposite of hammurabi.preconditions.attributes.HasMode.

made_changes

name

param

task() → bool

Check if the given mode is not set on the file or directory.

Returns

Returns True if the desired mode is not set

Return type

bool

class hammurabi.preconditions.attributes.IsNotOwnedBy(path: pathlib.Path, owner: str, **kwargs)

Bases: hammurabi.preconditions.attributes.IsOwnedBy

Opposite of hammurabi.preconditions.attributes.IsOwnedBy.

made_changes

name

param

task() → bool

Check if the ownership does not meet the requirements.

Returns

Returns True if the owner matches

Return type

bool

class hammurabi.preconditions.attributes.IsOwnedBy(path: pathlib.Path, owner: str, **kwargs)

Bases: hammurabi.preconditions.base.Precondition

Check if the given file or directory has the required ownership.

To check only the user use owner="username". To check only the group use owner=":group_name" (please note the colon :). It is also possible to check both username and group at the same time by using owner="username:group_name".

Example usage:

>>> from pathlib import Path
>>> from hammurabi import Law, Pillar, Renamed, IsOwnedBy
>>>
>>> example_law = Law(
>>>     name="Name of the law",
>>>     description="Well detailed description what this law does.",
>>>     rules=(
>>>         Renamed(
>>>             name="Rename pyproject.toml if owned by gabor",
>>>             path=Path("./pyproject.toml"),
>>>             new_name="gabor-pyproject.toml"
>>>             preconditions=[
>>>                 IsOwnedBy(path=Path("./pyproject.toml"), owner="gabor")
>>>             ]
>>>         ),
>>>     )
>>> )
>>>
>>> pillar = Pillar()
>>> pillar.register(example_law)

Parameters

• path (Path) – Input file’s path

• owner (str) – Owner user and/or group of the file/directory separated by colon

made_changes

name

param

task() → bool

Check if the ownership meets the requirements.

Returns

Returns True if the owner matches

Return type

bool

hammurabi.preconditions.base module

This module contains the definition of Preconditions which describes what to do with the received parameter and does the necessary changes. The preconditions are used to enable developers skipping or enabling rules based on a set of conditions.

Warning

The precondition is for checking that a rule should or shouldn’t run, not for breaking/aborting the execution. To indicate a precondition failure as an error in the logs, create a precondition which raises an exception if the requirements doesn’t match.

class hammurabi.preconditions.base.Precondition(name: Optional[str] = None, param: Optional[Any] = None)

Bases: hammurabi.rules.abstract.AbstractRule, abc.ABC

This class which describes the bare minimum and helper functions for Preconditions. A precondition defines what and how should be checked/validated before executing a Rule. Since preconditions are special rules, all the functions available what can be used for hammurabi.rules.base.AbstractRule.

As said, preconditions are special from different angles. While this is not true for Rules, Preconditions will always have a name, hence giving a name to a Precondition is not necessary. In case no name given to a precondition, the name will be the name of the class and ” precondition” suffix.

Example usage:

>>> import logging
>>> from typing import Optional
>>> from pathlib import Path
>>> from hammurabi import Precondition
>>>
>>> class IsFileExists(Precondition):
>>>     def __init__(self, path: Optional[Path] = None, **kwargs) -> None:
>>>         super().__init__(param=path, **kwargs)
>>>
>>>     def task(self) -> bool:
>>>         return self.param and self.param.exists()

Parameters

• name (Optional[str]) – Name of the rule which will be used for printing

• param (Any) – Input parameter of the rule will be used as self.param

execute() → bool

Execute the precondition.

Raise

AssertionError

Returns

None

made_changes

name

param

abstract task() → bool

Abstract method representing how a hammurabi.rules.base.Precondition.task() must be parameterized. Any difference in the parameters or return type will result in pylint/mypy errors.

To be able to use the power of pipe and children, return something which can be generally used for other rules as in input.

Returns

Returns an output which can be used as an input for other rules

Return type

Any (usually same as self.param’s type)

hammurabi.preconditions.directories module

This module contains the definition of Preconditions which are related to directories.

class hammurabi.preconditions.directories.IsDirectoryExists(path: pathlib.Path, **kwargs)

Bases: hammurabi.preconditions.base.Precondition

Check if the given directory exists.

Example usage:

>>> from pathlib import Path
>>> from hammurabi import Law, Pillar, Renamed, IsDirectoryExists
>>>
>>> example_law = Law(
>>>     name="Name of the law",
>>>     description="Well detailed description what this law does.",
>>>     rules=(
>>>         Renamed(
>>>             name="Rename the dir if an other one exists",
>>>             path=Path("old-name"),
>>>             new_name="new-name",
>>>             preconditions=[
>>>                 IsDirectoryExists(path=Path("other-dir"))
>>>             ]
>>>         ),
>>>     )
>>> )
>>>
>>> pillar = Pillar()
>>> pillar.register(example_law)

Parameters

path (Path) – Input directory’s path

made_changes

name

param

task() → bool

Check if the given directory exists.

Returns

Returns True if the directory exists

Return type

bool

class hammurabi.preconditions.directories.IsDirectoryNotExists(path: pathlib.Path, **kwargs)

Bases: hammurabi.preconditions.directories.IsDirectoryExists

Opposite of hammurabi.preconditions.directories.IsDirectoryExists.

made_changes

name

param

task() → bool

Check if the given directory not exists.

Returns

Returns True if the directory not exists

Return type

bool

hammurabi.preconditions.files module

Files preconditions module contains simple preconditions used for checking file existence.

class hammurabi.preconditions.files.IsFileExists(path: pathlib.Path, **kwargs)

Bases: hammurabi.preconditions.base.Precondition

Check if the given file exists.

Example usage:

>>> from pathlib import Path
>>> from hammurabi import Law, Pillar, Renamed, IsFileExists
>>>
>>> example_law = Law(
>>>     name="Name of the law",
>>>     description="Well detailed description what this law does.",
>>>     rules=(
>>>         Renamed(
>>>             name="Rename the file if an other one exists",
>>>             path=Path("old-name"),
>>>             new_name="new-name",
>>>             preconditions=[
>>>                 IsFileExists(path=Path("other-file"))
>>>             ]
>>>         ),
>>>     )
>>> )
>>>
>>> pillar = Pillar()
>>> pillar.register(example_law)

Parameters

path (Path) – Input files’s path

made_changes

name

param

task() → bool

Check if the given file exists.

Returns

Returns True if the file exists

Return type

bool

class hammurabi.preconditions.files.IsFileNotExists(path: pathlib.Path, **kwargs)

Bases: hammurabi.preconditions.files.IsFileExists

Opposite of hammurabi.preconditions.files.IsFileExists.

made_changes

name

param

task() → bool

Check if the given file not exists.

Returns

Returns True if the file not exists

Return type

bool

hammurabi.preconditions.text module

This module contains the definition of Preconditions which are related to general text files.

class hammurabi.preconditions.text.IsLineExists(path: pathlib.Path, criteria: str, **kwargs)

Bases: hammurabi.preconditions.base.Precondition

Check if the given line exists.

Example usage:

>>> from pathlib import Path
>>> from hammurabi import Law, Pillar, Renamed, IsLineExists
>>>
>>> example_law = Law(
>>>     name="Name of the law",
>>>     description="Well detailed description what this law does.",
>>>     rules=(
>>>         Renamed(
>>>             name="Rename the file if an other one exists",
>>>             path=Path("old-name"),
>>>             new_name="new-name",
>>>             preconditions=[
>>>                 IsLineExists(path=Path("other-file"), criteria=r"^string=some-value$")
>>>             ]
>>>         ),
>>>     )
>>> )
>>>
>>> pillar = Pillar()
>>> pillar.register(example_law)

Parameters

• path (Path) – Input files’s path

• criteria (str) – Regexp of the desired line

made_changes

name

param

task() → bool

Check if the given line exists.

Returns

Returns True if the line exists

Return type

bool

class hammurabi.preconditions.text.IsLineNotExists(path: pathlib.Path, criteria: str, **kwargs)

Bases: hammurabi.preconditions.text.IsLineExists

Opposite of hammurabi.preconditions.text.IsLineExists.

made_changes

name

param

task() → bool

Check if the given line not exists.

Returns

Returns True if the line not exists

Return type

bool

Module contents