update docs in readme, add CLI section

README.md

@@ -1,16 +1,93 @@
 # pytest-abra
-...description...
+
+Pytest-Abra is an installable python package design to test instances created with [abra](https://docs.coopcloud.tech/abra/). After installation, you will have two things:
+
+- `abratest` CLI command
+
+- `pytest-abra` Pytest plugin
+
+## CLI (abratest)
+
+The easiest way to call abratest is via the helper script in `main.py`. You can also directly call abratest via terminal, but you will have to make sure that the requirements below are met. To do that, you can call `abratest` with:
+
+```bash
+abratest [arguments]
+```
+
+The cli command abratest has 3 **required arguments**:
+
+- `--env_paths`: list of the .env files used in the test
+- `--recipes_dir`: directory of all available abra recipes
+- `--output_dir`: target directory for all test results
+
+It is also absolutely necessary, that python can import from `recipes_dir`. This can be achieved by adding the path to the `PYTHONPATH` environment variable **before** the python interpreter is started, i.e. before `abratest` is called.
+
+### env_paths [string]
+
+The variable env_paths consists of one or more paths pointing at .env files. The paths are separated with ";". These .env files are actually configuration files for `abra` recipes, but `pytest-abra` uses the same files for test configuration.
+
+To run `abratest` with these `.env` configuration files
+
+```
+/path/to/config_1.env
+/path/to/config_2.env
+/path/to/config_3.env
+```
+
+we simply call
+
+```
+abratest --env_paths /path/to/config_1.env;/path/to/config_2.env;/path/to/config_3.env
+```
+
+Under the hood, each `.env` file in `--env_paths` will create one instance of a `Runner` subclass. Let's say we have `wordpress_configuration.env` containing `TYPE=wordpress`. This will create an instance of `RunnerWordpress`. This class has to be imported from `recipes_dir`.
+
+### recipes_dir [string]
+
+The required argument `--recipes_dir` has to point to the directory, where all the abra recipes are stored. We cann call `abratest` with
+
+```
+abratest --recipes_dir /path/to/abra/recipes
+```
+
+```
+DIR recipes_dir [contains abra recipes]
+│
+├── DIR authentik [authentik recipe]
+│   ├── [files from authentik recipe]
+│   └── DIR tests_authentik [pytest tests for authentik]
+│       ├── FILE runner_authentik.py  # containing RunnerAuthentik class
+│       └── [pytest_files]
+│
+└── DIR wordpress [wordpress recipe]
+    ├── [files from wordpress recipe]
+    └── DIR tests_wordpress [pytest tests for wordpress]
+        ├── FILE runner_wordpress.py  # containing RunnerWordpress class
+        └── [pytest_files]
+```
+
+The class `RunnerWordpress` will be imported via
+
+```python
+from wordpress.tests_wordpress.runner_wordpress import RunnerWordpress
+```
+
+which requires that python can find and import from the module `wordpress`. One way to achive this is by adding recipes_dir to the environment variable PYTHONPATH before
+i.e. abratest cannot do this itself
+-> workaround?
+todo
 
 # Usage
 
 To use pytest-abra, follow these steps:
 
-## 1. GIT Clone
+## 1. GIT clone [with & without Docker]
 
 To clone with submodules, use these git commands:
 
 ```bash
 git clone --recurse-submodules <repository>
+// optional:
 git submodule update --init    // add submodule after normal cloning
 git submodule update --remote  // update submodules
 ```