Tutorial: Xonsh Projects#

Bam! Suppose you want to get beyond scripting and write a whole library, utility, or other big project in xonsh. Here is how you do that. Spoiler alert: it is easy, powerful, and fun!


Xonsh is fully interoperable with Python. Writing a xonsh library is very similar to writing a Python library, using all of the same tooling and infrastructure for packaging pure Python code.


Xonsh modules are written in xonsh files (*.xsh), side-by-side with Python files (*.py). Suppose we have a package called mypkg which uses xonsh files. Here is a sample file system layout would be:

|- mypkg/
   |- __init__.py    # a regular package with an init file
   |- other.py       # not a xonsh file
   |- show.py        # "mypkg.show", full module name
   |- tell.xsh       # "mypkg.tell", full module name
   |- subpkg/
      |- __init__.py
      |- a.py      # "mypkg.subpkg.a", full module name
      |- b.xsh     # "mypkg.subpkg.b", full module name

To ensure that these files are installed, you need to provide the appropriate information in setup.py file for your project. For the above structure, this looks like the following.


    packages=['mypkg', 'mypkg.subpkg'],
    package_dir={'mypkg': 'mypkg', 'mypkg.subpkg': 'mypkg/subpkg'},
    package_data={'mypkg': ['*.xsh'], 'mypkg.subpkg': ['*.xsh']},

With this, the xonsh code will be installed and included in any source distribution you create!

Setting up xonsh sessions#

Xonsh code requires a XonshSession to exist as builtins.__xonsh__ and for be that object to be setup correctly. This can be quite a bit of work and the exact setup depends on the execution context. To simplify the process of constructing the session properly, xonsh provides the xonsh.main.setup() function specifically for use in 3rd party packages.

While xonsh.main.setup() is safely re-entrant, it is a good idea to add the following snippet to the root-level __init__.py of your project. With the mypkg example above, the session setup is as follows:


from xonsh.main import setup
del setup