lockss-pybasic 0.2.0.dev17

Basic Python utilities

Latest release: 0.2.0-dev17 (NOT YET RELEASED)

lockss-pybasic provides basic utilities for various LOCKSS projects written in Python.

Modules

lockss.pybasic.cliutil

Command line utilities.

• BaseCli is a base class for command line interfaces that uses pydantic-argparse to define arguments and subcommands, and rich-argparse to display help messages. For each command x-y-z induced by a pydantic-argparse field named x_y_z deriving from BaseModel , the dispatch() method expects a method named _x_y_z.

• StringCommand provides a pydantic-argparse way to define a subcommand whose only purpose is printing a string, with COPYRIGHT_DESCRIPTION, LICENSE_DESCRIPTION and VERSION_DESCRIPTION constants provided for convenience. Example:

  class MyCliModel(BaseModel):
      copyright: Optional[StringCommand.type(my_copyright_string)] = Field(description=COPYRIGHT_DESCRIPTION)

• at_most_one_from_enum and get_from_enum provide a facility for defining a pydantic-argparse model that defines one command line option per constant of an Enum, using an enum keyword argument in the Field definition. Example:

  class Orientation(Enum):
      horizontal = 1
      vertical = 2
      diagonal = 3
  
  DEFAULT_ORIENTATION = Orientation.horizontal
  
  class MyCliModel(BaseModel):
      diagonal: Optional[bool] = Field(False, description='display diagonally', enum=Orientation)
      horizontal: Optional[bool] = Field(False, description='display horizontally', enum=Orientation)
      unrelated: Optional[bool] = Field(...)
      vertical: Optional[bool] = Field(False, description='display vertically', enum=Orientation)
  
      @root_validator
      def _at_most_one_orientation(cls, values):
          return at_most_one_from_enum(cls, values, Orientation)
  
      def get_orientation(self) -> Orientation:
          return get_from_enum(self, Orientation, DEFAULT_ORIENTATION)

lockss.pybasic.errorutil

Error and exception utilities.

• InternalError is a no-arg subclass of RuntimeError.

lockss.pybasic.fileutil

File and path utilities.

• file_lines returns the non-empty lines of a file stripped of comments that begin with # and run to the end of a line.

• path takes a string or PurePath and returns a Path for which Path.expanduser() and Path.resolve() have been called.

lockss.pybasic.outpututil

Utilities to work with tabulate.

• OutputFormat is an Enum of all the output formats from tabulate.tabulate_formats.

• OutputFormatOptions defines a pydantic-argparse model for setting an output format from OutputFormat.

Release Notes

See CHANGELOG.rst.