mosaik.EId 0.1.0rc20190329152904

A utility for managing mosaik's entity identifiers.

# Mosaik EID

Mosaik EID supports creating Mosaik scenarios by managing the identifiers of the
entities.

## Motivation

Traditionally, mosaik entities are created with hard coded names.
Mosaik EID intends to be easier to use and less error-prone than to hard coding values.
The clean and pythonic API encourages creating scenarios in a DRY fashion.

## Design

The package contains a parser, generator, data model and exceptions around creating such names.
The data model is based upon an
[`Enum`](https://docs.python.org/3/library/enum.html).
Building upon that is a manager which issues entity identifiers
based on the entity type and a serial number.
The entity manager implements the borg pattern and
can thus be instantiated at will without losing state.
There are some basic entity types predefined,
but they can be extended by registering additional types.

## Compatibility

It is allowed to register entity names with arbitrary capitalization,
for example `CHP`, `BioGas` or `wind` or `lv_bat_liion_3_5_10`.
All components are tested with 100 % test coverage and hopefully many corner cases
caught.
There are extensive unit, integration and functional tests.
Tests are integrated into tox to ensure compatibility across some python
implementations.
These are: CPython 2.7, CPython 3.5, Python 3.6, CPython 3.7, PyPy2v6 and PyPy3v6

## Limitations

- Thread safety is not yet implemented because it seems to have little value.
- Entity types need to be valid [Python identifiers](https://docs.python.org/2/reference/lexical_analysis.html#identifiers).

- PyPy3 does not currently work under Windows 10 because of an unresolved [a bug in pypy](https://bitbucket.org/pypy/pypy/issues/2816/cannot-install-cppyy-on-windows).

## Tests

This package uses
[`unittest`](https://docs.python.org/3.4/library/unittest.html)
for writing tests,
[`nose`](https://nose.readthedocs.org/en/latest/)
for test discovery and
[`tox`](https://tox.readthedocs.org/en/latest/)
for running them on multiple python versions.

## Cloning the Source

git clone https://eprojects.offis.de/mosaik-eid/git/mosaik-eid.git

## Creating the Virtual Environment

Under Linux:

virtualenv -p python3.7 venv

Under Windows:

virtualenv -p "C:\Program Files\Python37\python.exe" venv

## Activating the Virtual Environment

Under BASH:

source venv/bin/activate

Under CMD:

venv/Scripts/activate

# Installing the Requirements

python -m pip install -r requirements.d/venv.txt

# Running the Tests

tox

## Testing the Coverage

python -m coverage html mosaik_eid/*.py

Under Linux

xdg-open htmlcov/index.html

Under Windows

start htmlcov/index.html

## Using the Library

>>> from mosaik_eid.eid_registry import EidRegistry
>>> e_type = EntityTypeRegistry.register(e_type='biogas')
>>> for _ in range(3):
... next(EidManager(e_type=e_type))
...
'biogas-0'
'biogas-1'
'biogas-2'

See `tests/functional` for more practical examples of intended use.

## Developing the Library

For development purposes,
use one of the virtual environment under .tox your choice.

## Freezing the Requirements

(venv) python -m pip freeze --all > requirements.d/venv.txt

(py37) python -m pip freeze --all > requirements.d/base.txt
# And remove line beginning with "mosaik_EId"