Travis setup

Tue 12 May 2020
One job in continuous integration pipeline (Photo credit: Wikipedia)

The goal is to setup a CI pipeline based on Travis with external dependencies integrated to a Github repository

Travis basics

To enable Travis integration in Github, one must edit ./.travis.yml file.

I won't go into detail. The setup is documented in the official tutorials and is straight forward. All your Github repository will be listed on your Travis home page. The official documentation propose a default file:

language: python
     - "2.7"
     - "3.4"
     - "3.5"
     - "3.6"      # current default Python on Travis CI
     - "3.7"
     - "3.8"
     - "3.8-dev"  # 3.8 development branch
     - "nightly"  # nightly build
     # command to install dependencies
     - pip install -r requirements.txt
     # command to run tests
     - pytest

This works (if you have setup tests runnable with pytest). Yet, python version does not need to include the older one, neither the unstable one. That means when updating your python version, you must update your Travis file.

When pushing a commit to Github, the Travis pipeline will be triggered, and if all tests pass, a tick will appear in the list of commit on Github.

Small tick appearing on Github commit list


When the CI tests fail, you can see Travis logs. A commit trigger a Travis build, and a build can be composed of several jobs. For example, there is one job per python version. Each job generate its log. The log contain all command run and its results.

Package installation

Your project may require extra dependencies. Let's see how to install them.

Extra scripts

You can custom the install section of your Travis file. You can put multiple steps on this section: If you use a requirements.txt:

language: python
     - "3.8"
     - pip install -r requirements.txt
     - make install
     - pytest


For python projects, given that you may have more steps to do for installation, the prefered way to do this is to use a <>_. The minimal I recommand use only the setup() function with the following arguments:

  • install_requires for requirements (if needed, read from requirements.txt)
  • packages
  • package_dir to avoid manipulating PYTHONPATH manually

Thus, the, located at the root of the project, contains

#!/usr/bin/env python

from distutils.core import setup

  package_dir={"": "src"},

To run this, you can pip install your project:

  - pip install .


The CI runs on ubuntu virtual machines. Thus, you can add a list of packages that can be installed. This is done through the add-on section:

language: python
       - texlive-full
       - pandoc
     - "3.8"
     - pip install .
     - pytest -v

Category: howto Tagged: travis ci howto

Wikidata crawling

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Graph database representation (Photo credit: Wikipedia)

I wish to have reliable data about vehicles. I decided to rely on one large source, namely Wikipedia. I chose it because it is reviewable and most of the time reviewed, and regularly updated and completed.

Wikipedia - Wikidata relationship

Wikidata items are made to …

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Second order differential equation (Photo credit: Wikipedia)

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Zombie favorite food warning (Photo credit: wikipedia)

I recently read a paper [1] trying to model a disease propagation. I wanted to play with this model.

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Virtual environement (Photo credit: wikipedia)

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aileron Vertical stabilizer (Photo credit: Wikipedia)

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LaTeX makefile updated

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My default LaTeX makefile evolved. Here is an update:

The makefile looks like:

RERUN='(There is undefined reference|Rerun to get (cross-references|the bars) right)'

    ${LATEX} $<
    @if [ -e $*.bbl ]; then ${BIBTEX} $* && ${LATEX} $< && ${LATEX} $< ; fi
    @if egrep -q $(RERUN) $*.log ; then ${LATEX} $< ; fi

%.aux …

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