Developer’s guide


pyexcel uses loosely couple plugins to fullfil the promise to access various file formats. lml is the plugin management library that provide the specialized support for the loose coupling.

The components of pyexcel is designed as building blocks. For your project, you can cherry-pick the file format support without affecting the core functionality of pyexcel. Each plugin will bring in additional dependences. For example, if you choose pyexcel-xls, xlrd and xlwt will be brought in as 2nd level depndencies.

Looking at the following architectural diagram, pyexcel hosts plugin interfaces for data source, data renderer and data parser. pyexel-pygal, pyexcel-matplotlib, and pyexce-handsontable extend pyexcel using data renderer interface. pyexcel-io package takes away the responsibilities to interface with excel libraries, for example: xlrd, openpyxl, ezodf.

As in A list of file formats supported by external plugins, there are overlapping capabilities in reading and writing xlsx, ods files. Because each third parties express different personalities although they may read and write data in the same file format, you as the pyexcel is left to pick which suit your task best.

Dotted arrow means the package or module is loaded later.


Development steps for code changes

  1. git clone
  2. cd pyexcel

Upgrade your setup tools and pip. They are needed for development and testing only:

  1. pip install –upgrade setuptools pip

Then install relevant development requirements:

  1. pip install -r rnd_requirements.txt # if such a file exists
  2. pip install -r requirements.txt
  3. pip install -r tests/requirements.txt

Once you have finished your changes, please provide test case(s), relevant documentation and update CHANGELOG.rst.


As to rnd_requirements.txt, usually, it is created when a dependent library is not released. Once the dependecy is installed (will be released), the future version of the dependency in the requirements.txt will be valid.

How to test your contribution

Although nose and doctest are both used in code testing, it is adviable that unit tests are put in tests. doctest is incorporated only to make sure the code examples in documentation remain valid across different development releases.

On Linux/Unix systems, please launch your tests like this:

$ make

On Windows systems, please issue this command:

> test.bat

How to update test environment and update documentation

Additional steps are required:

  1. pip install moban
  2. git clone # generic setup
  3. git clone commons
  4. make your changes in .moban.d directory, then issue command moban

What is pyexcel-commons

Many information that are shared across pyexcel projects, such as: this developer guide, license info, etc. are stored in pyexcel-commons project.

What is .moban.d

.moban.d stores the specific meta data for the library.

Acceptance criteria

  1. Has Test cases written
  2. Has all code lines tested
  3. Passes all Travis CI builds
  4. Has fair amount of documentation if your change is complex
  5. Please update CHANGELOG.rst
  6. Please add yourself to CONTRIBUTORS.rst
  7. Agree on NEW BSD License for your contribution