Kent

Kent is a service for debugging and integration testing Sentry.

Code: https://github.com/willkg/kent/
Issues: https://github.com/willkg/kent/issues
License: MPL v2

Goals

Goals of Kent:

  1. make it possible to debug before_send and before_breadcrumb
    sanitization code when using sentry-sdk
  2. make it possible to debug other sentry error submission payload issues
  3. make it possible to write integration tests against a fake sentry instance

Quick start

Installing and running on your local machine

  1. Install Kent.

    You can install Kent from PyPI with pipx or pip or whatever:

    pipx install kent

    You can install a REVISH (“main”, branch name, commit, whatever) from
    GitHub:

    pipx install https://github.com/willkg/kent/archive/refs/heads/<REVISH>.zip

    You can install from a checked out version of this repository:

    pipx install .

  2. Run Kent:

    kent-server run [-h HOST] [-p PORT]

Running in a Docker container

I’m using something like this:

FROM python:3.10.1-alpine3.15

WORKDIR /app/

ENV PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1

RUN pip install -U 'pip>=8' && \
    pip install --no-cache-dir 'kent==VERSION'

USER guest

ENTRYPOINT ["/usr/local/bin/kent-server"]
CMD ["run"]

Replace VERSION with the version of Kent you want to use. See
https://pypi.org/project/kent for releases.

Then:

$ docker build -t faksentry:latest .
$ docker run --rm --publish 8000:8000 fakesentry:latest run --host 0.0.0.0 --port 8000

Things to know about Kent

Kent is the fakest of fake Sentry servers. It supports a single Sentry project
with id 1. You can set up a Sentry DSN to point to Kent and have your
application send errors.

Kent is a refined fake Sentry service and doesn’t like fast food.

Kent will keep track of the last 100 it received in memory. Nothing is
persisted to disk.

You can access the list of errors and error data with your web browser by going
to Kent’s index page.

You can also access it with the API. This is most useful for integration tests
that want to assert things about errors.

/api/errorlist/
List of all errors in memory with a unique error id.
/api/error/ERRORID
Retrieve the payload for a specific error by id.
/api/flush/
Flushes the error manager of all errors.

Kent definitely works with:

  • Python sentry-sdk client

I don’t know about anything else. If you use Kent with another Sentry client,
add an issue with details or a pull request to update the README.

Release process

  1. Check out main tip.

  2. Update __version__ in src/kent/__init__.py.

  3. Run:

    $ make checkrot
$ make test
$ make testdocker
$ check-manifest

    Fix any issues from that.

  4. Update HISTORY.rst.

  5. Push any changes to GitHub.

  6. Release:

    $ git tag --sign 1.0.0
# Use contents from HISTORY.rst for tag comment

$ make clean
$ python setup.py sdist bdist_wheel
$ twine upload dist/*

GitHub

View Github