rickhanlonii / imhotep

A static-analysis bot for Github

Imhotep, the peaceful builder.

What is it?

Imhotep is a tool which will comment on commits coming into your repository and check for syntactic errors and general lint warnings.

Want a hosted version?

There's a hosted version of this at https://betterdiff.com with an actual support team, etc. If your company is interested in imhotep, consider checking it out.

Installation

Currently, installation is done from source through Python packaging system. We first need to download it from GitHub. We then setup a virtualenv which will keep our python packages separate from other things on your system, lest we have version conflicts. Finally, we install the required packages.

virtualenv env
. env/bin/activate
pip install imhotep

If you want to hack on imhotep, that looks more like this:

git clone git://github.com/justinabrahms/imhotep.git
cd imhotep
virtualenv env
. env/bin/activate
pip install -r requirements.txt
pip install -e .

You'll also need to install the plugins you'd like to run. Examples include jshint, flake8, pep8, pylint, rubocop, foodcritic, and jsl. You can install those with pip. Example: pip install imhotep_jshint.

Usage

To use imhotep, we must tell it which repository to look at, who to authenticate as and what to comment on. Imhotep is able to comment in two ways: either on a single commit or on a pull request.

Commenting on a pull request

    imhotep \
       --repo_name="justinabrahms/imhotep" \
       --github-username="your_username" \
       --github-password="a_sha_generated_by_github" \
       --pr-number=1

Commenting on a single commit

    imhotep \
       --repo_name="justinabrahms/imhotep" \
       --github-username="your_username" \
       --github-password="a_sha_generated_by_github" \
       --commit="a123445714cfa89d1e843d9950ea8f249cd6e4df"

Where do I get that SHA?

The SHA generated by github is done through your user's settings page. Generate a personal access token and use that for the --github-password above.

Full Usage Info

usage: imhotep [-h] [--config-file CONFIG_FILE] --repo_name REPO_NAME
               [--commit COMMIT] [--origin-commit ORIGIN_COMMIT]
               [--filenames FILENAMES [FILENAMES ...]] [--debug]
               [--github-username GITHUB_USERNAME]
               [--github-password GITHUB_PASSWORD] [--no-post]
               [--authenticated] [--pr-number PR_NUMBER]
               [--cache-directory CACHE_DIRECTORY]

Posts static analysis results to github.

optional arguments:
  -h, --help            show this help message and exit
  --config-file CONFIG_FILE
                        Configuration file in json.
  --repo_name REPO_NAME
                        Github repository name in owner/repo format
  --commit COMMIT       The sha of the commit to run static analysis on.
  --origin-commit ORIGIN_COMMIT
                        Commit to use as the comparison point.
  --filenames FILENAMES [FILENAMES ...]
                        filenames you want static analysis to be limited to.
  --debug               Will dump debugging output and won't clean up after
                        itself.
  --github-username GITHUB_USERNAME
                        Github user to post comments as.
  --github-password GITHUB_PASSWORD
                        Github password for the above user.
  --no-post             [DEBUG] will print out comments rather than posting to
                        github.
  --authenticated       Indicates the repository requires authentication
  --pr-number PR_NUMBER
                        Number of the pull request to comment on
  --cache-directory CACHE_DIRECTORY
                        Path to directory to cache the repository

Note: if you get a error where the plugin cannot find imhotep.tools, make sure you installed imhotep into your virtualenv with pip install -e .. See the Installation instructions above.

Linter Support

There is currently support for 2 linters: PyLint and JSHint. If it finds violations, it will post those violations to GitHub. New linting tools are encouraged!

By default, imhotep runs all plugins it can find on your source code. If you'd like to only run a subset of linters, you should specify the --linter directive with a dotted path to the module. An example of this is imhotep.tools:PyLint or imhotep_pep8.plugin:Pep8Linter. If you want to specify multiple tools, just pass multiple things to the --linter flag.

Writing Plugins

Imhotep supports adding linters through a plugin API based around Python's setuptools entrypoints. This means that plugins can live as separate Python packages which are installable alongside imhotep.

To write your own tool, subclass the Tool class and override the process_line, get_file_extensions, and get_command methods. If you need greater control over how the tool is run, you can override the invoke method which gives you maximal control over how the tools are run.

To make your plugin discoverable, you need to add an entry_points stanza to your setup.py. It looks like this.

setup(
  # ...
  entry_points={
    'imhotep_linter': [
      '.py = path.to.module:ToolClassName'
    ]
  }
  # ...
)

The key pieces of this are the name of the entrypoint which must be imhotep_linter. This is how we know where to find the plugins. The list that follows it is a list of strings that map file extensions to a tool that knows how to lint them. So for the entry above, we'll do something like from path.to.module import ToolClassName and run that on all .py files in the repository.

You can find a working example of a setup.py file in the imhotep_pep8 repository.

What's with the name?

Imhotep, the first Egyptian architect, is known as "the one who comes in peace". In keeping with that name, the goal of this tool is to keep code reviews peaceful and productive by having robots point out the nitpicky details, leaving people to critique bigger picture things, not spacing and misspelling issues.