Update Readme to explain tests

README.md

@@ -78,6 +78,8 @@ flake8 backend/
 python -m pytest
 ```
 
+For more information on running the tests, see the [backend tests README](./backend/tests/README.md)
+
 ### Front End Tests
 
 The current frontend tests can be found in the GitHub Actions workflow file [frontend-checks.yml](https://github.com/codeforboston/police-data-trust/blob/0488d03c2ecc01ba774cf512b1ed2f476441948b/.github/workflows/frontend-checks.yml)

backend/tests/README.md

@@ -1,5 +1,43 @@
-To run tests locally:
+To run backend tests locally:
 
-```shell
-python -m pytest
+## Pytest (Unit Tests)
+
+1. Start the application cluster with `docker-compose up`
+
+2. Start the test database with `docker-compose --profile test up`.
+Yes, you should start the test database separately. It'll be more likely to boot properly this way.
+
+3. Add a test marker to the test DB. This will allow the DB to clear itself after each test run. See instructions below.
+
+4. Connect to the API container with `docker exec -it "police-data-trust-api-1" /bin/bash`. You can find the container name by running `docker ps`.
+
+5. Run the tests with `python -m pytest`.
+
+6. If you want to run a specific test file, you can do so with `python -m pytest <path_to_test_file>`. You can also run a specific test with `python -m pytest <path_to_test_file>::<test_function_name>`.
+
+
+## Adding a test marker to the test database
+
+1. With the test database running, navigate to `localhost:7474` in your browser.
+
+2. On the Neo4J web interface, select `neo4j://127.0.0.1:7688` as the connection URL. Otherwise, you will connect to the main database.
+
+3. Log in with the username `neo4j` and the password `test_pwd`.
+
+4. Run the following query to add a test marker to the database:
+
+```
+MERGE (n:TestMarker {name: 'TEST_DATABASE'});
+```
+
+5. You can now run the tests. The database will clear itself after each test run.
+
+
+## Flake8 (Linting)
+
+1. Start the application cluster with `docker-compose up`
+
+2. Connect to the API container with `docker exec -it "police-data-trust-api-1" /bin/bash`. You can find the container name by running `docker ps`.
+
+3. Run the linter with `flake8 backend/`.
 ```