# BigchainDB Server Tests

## The tests/ Folder

The `tests/` folder is where all the tests for BigchainDB Server live. Most of them are unit tests. Integration tests are in the [`tests/integration/` folder](./integration/).

A few notes:

- [`tests/common/`](./common/) contains self-contained tests only testing
  [`bigchaindb/common/`](../bigchaindb/common/)
- [`tests/backend/`](./backend/) contains tests requiring
  the database backend (MongoDB)


## Writing Tests

We write unit and integration tests for our Python code using the [pytest](http://pytest.org/latest/) framework. You can use the tests in the `tests/` folder as templates or examples.


## Running Tests

### Running Tests Directly

If you installed BigchainDB Server using `pip install bigchaindb`, then you
didn't install the tests. Before you can run all the tests, you must install
BigchainDB from source. The [`CONTRIBUTING.md` file](../CONTRIBUTING.md) has
instructions for how to do that.

Next, make sure you have Local MongoDB running in the background. You
can run MongoDB using `mongod`.

The `pytest` command has many options. If you want to learn about all the
things you can do with pytest, see [the pytest
documentation](http://pytest.org/latest/). We've also added a customization to
pytest:

`--database-backend`: Defines the backend to use for the tests. It defaults to
`localmongodb`.

Now you can run all tests using:
```text
pytest -v
```

or, if that doesn't work, try:
```text
python -m pytest -v
```

or:
```text
python setup.py test
```

How does `python setup.py test` work? The documentation for [pytest-runner](https://pypi.python.org/pypi/pytest-runner) explains.

The `pytest` command has many options. If you want to learn about all the things you can do with pytest, see [the pytest documentation](http://pytest.org/latest/). We've also added a customization to pytest:


### Running Tests with Docker Compose

You can also use [Docker Compose](https://docs.docker.com/compose/) to run all the tests.

First, bring up all the services BigchainDB, MongoDB, Tendermint in the background:

```text
$ docker-compose up -d bdb
```

then run the tests using:

```text
$ docker-compose run --rm --no-deps bigchaindb pytest -v
```

## Automated Testing of All Pull Requests

We use [Travis CI](https://travis-ci.com/), so that whenever someone creates a new BigchainDB pull request on GitHub, Travis CI gets the new code and does _a bunch of stuff_. We use the same `docker-compose.yml` for tests. It tells Travis CI how to install BigchainDB, how to run all the tests, and what to do "after success" (e.g. run `codecov`). (We use [Codecov](https://codecov.io/) to get a rough estimate of our test coverage.)


### Tox

We use [tox](https://tox.readthedocs.io/en/latest/) to run multiple suites of tests against multiple environments during automated testing. Generally you don't need to run this yourself, but it might be useful when troubleshooting a failing Travis CI build.

To run all the tox tests, use:
```text
tox
```

or:
```text
python -m tox
```

To run only a few environments, use the `-e` flag:
```text
tox -e {ENVLIST}
```

where `{ENVLIST}` is one or more of the environments specified in the [tox.ini file](../tox.ini).