Obtaining the Python tdda Library

Posted on Thu 14 September 2017 in TDDA

This post is a standing post that we plan to try to keep up to date, describing options for obtaining the open-source Python TDDA library that we maintain.

Using pip from PyPI

If you don't need source, and have Python installed, the easiest way to get the TDDA library is from the Python package index PyPI using the pip utility.

Assuming you have a working pip setup, you should be able to install the tdda library by typing:

pip install tdda

or, if your permissions don't allow use in this mode

sudo pip install tdda

The tdda library supports both Python 2 (version 2.7) and Python 3.

Installing from Source

The source for the tdda library is available from Github and can be cloned with

git clone https://github.com/tdda/tdda.git

or

git clone git@github.com:tdda/tdda.git

When installing from source, if you want the command line tdda utility to be available, you need to run

python setup.py install

from the top-level tdda directory after downloading it.

Documentation

The main documentation for the tdda library is available on Read the Docs.

You can also build it youself if you have downloaded the source from Github. In order to do this, you will need an installation of Sphinx. The HTML documentation is built, starting from the top-level tdda directory by running:

cd doc
make html

Running TDDA's tests

Once you have installed TDDA (whether using pip or from source), you can run its tests by typing

tdda test

If you have all the dependencies, including optional dependencies, installed, you should get a line of dots and the message OK at the end, something like this:

$ tdda test
........................................................................................................................
----------------------------------------------------------------------
Ran 122 tests in 3.251s

OK

If you don't have some of the optional dependencies installed, some of the dots will be replaced by the letter 's'. For example:

$ tdda test
.................................................................s.............................s........................
----------------------------------------------------------------------
Ran 120 tests in 3.221s

OK (skipped=2)

This does not indicate a problem, and simply means there will be some of the functionality unavailable (e.g. usually one or more database types).

Using the TDDA examples

The tdda library includes three sets of examples, covering reference testing, automatic constraint discovery and verification, and Rexpy (discovery of regular expressions from examples, outside the context of constraints).

The tdda command line can be used to copy the relevant files into place. To get the examples, first change to a directory where you would like them to be placed, and then use the command:

tdda examples

This should produce the following output:

Copied example files for tdda.referencetest to ./referencetest-examples
Copied example files for tdda.constraints to ./constraints-examples
Copied example files for tdda.rexpy to ./rexpy-examples

Quick Reference Guides

There is a quick reference guides available for the TDDA library. These are often a little behind the current release, but are usually still quite helpful.

These are available from here.

Tutorial from PyData London

There is a video online of a workshop at PyData London 2017. Watching a video of a workshop probably isn't ideal, but it does have a fairly detailed and gentle introduction to using the library, so if you are struggling, it might be a good place to start.