Mininet Python Style

Mininet is currently written in the Mininet Python Style, which is based on the Arista Networks Python style. It mainly follows PEP8, but differs in several important ways, including the following:

• Spaces are inserted inside parentheses, such as those in function definitions and calls, for readability. They may be omitted in mathematical formulas if readability would otherwise be compromised.

• camelCase is used for method and variable names in preference to under_scores. This is intended to give named identifiers (including those for classes, methods, instance variables, local variables, and parameters) a more consistent look and to reduce cognitive load. However, for easier filename typing, core Mininet package names (nodelib, topolib, etc.) are usually lowercase.

• Single-line docstrings are surrounded by single double-quotes. This makes them more compact.

• Multi-line docstrings are surrounded by triple double-quotes. This differs from single-line docstrings, which use single quotes. The ending triple-quote is at the end of the last line of docstring text, and text is lined up as shown below.

The Mininet code style can be checked (more or less) by running make codecheck. A utility to help with conversion from PEP8 to Mininet style is provided as util/unpep8.

Mininet also uses doxypy for automatic API documentation. We run a pre-processor which eliminates most uses of the @ character in docstrings. For example:

def someFunction( someArg, anotherArg=False ):
   """This function does something
      someArg: an argument
      anotherArg: another argument
      returns: True on success"""
   return True

The utility util/doxify.py converts this format into something that can be parsed by doxypy.