readme notes e2e testings (#69)

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README.md

@@ -4,6 +4,88 @@
 
 An integration layer allowing Ansible Rulebook to use Drools as rule engine for rules evaluation. Drools can be invoked from Ansible either via a REST API or natively through [jpy](https://pypi.org/project/jpy/).
 
+## Manual end-to-end testing with `drools_jpy` and `ansible-rulebook`
+
+Assuming the following local setup:
+
+```
+.
+├── ansible-rulebook
+├── drools-ansible-rulebook-integration
+└── drools_jpy
+```
+
+For the Python projects, creating a common, shared [virtual environment](https://packaging.python.org/en/latest/glossary/#term-Virtual-Environment) instance is strongly advised, in order to be shared between `drools_jpy` and `ansible-rulebook`.
+You can opt for ansible-rulebook to "borrow" the venv from drools_jpy.
+Another strategy is to use a venv strategically placed (personally used `~/venv/bin/activate`).
+
+To create the venv:
+
+```
+python3 -m venv {destination directory}
+```
+
+e.g.:
+
+```sh
+python3 -m venv ~/venv
+```
+
+Ref: https://packaging.python.org/en/latest/guides/installing-using-pip-and-virtual-environments
+
+Assuming the Python requirements were already installed for the projects:
+
+- https://ansible.readthedocs.io/projects/rulebook/en/stable/development_environment.html
+- https://github.com/ansible/drools_jpy#setup-and-testing 
+
+The following steps illustrate how to perform end-to-end testing.
+
+### Step 1 (drools-ansible-rulebook-integration)
+
+Build locally with Maven, then copy the runtime JAR to drools_jpy:
+
+(from `drools-ansible-rulebook-integration`)
+
+```sh
+mvn clean install
+cp drools-ansible-rulebook-integration-runtime/target/drools-ansible-rulebook-integration-runtime-1.0.3-SNAPSHOT.jar ../drools_jpy/src/drools/jars/
+```
+
+### Step 2 (drools_jpy)
+
+Use the shared venv, run the test with very-verbose and non-caputuring output, following by building (in venv site):
+
+(from `drools_jpy`)
+
+```sh
+source ~/venv/bin/activate
+pytest -vv -s
+python3 -m pip install .
+```
+
+### Step 3 (ansible-rulebook)
+
+Use the same shared venv (so to find the specific version of drools_jpy), run the tests:
+
+(from `ansible-rulebook`)
+
+```sh
+pip install -e .
+pip install -r requirements_dev.txt
+pytest -m "e2e" -n auto 
+pytest -m "not e2e and not long_run" -vv -n auto
+```
+
+You can always run all the tests with:
+
+```sh
+pytest
+```
+
+### Notes
+
+An example of the strategy in practice: https://github.com/kiegroup/drools-ansible-rulebook-integration/pull/64
+
 ## Installing and Running REST API service
 
 ### Prerequisites