Update contributing guide docs (#591)

- Remove repetitive instructions
- Add instructions for Linux to prevent permission errors when running the docker-compose command

Closes #588

(cherry picked from commit d829a04)

docs/contributing.rst

@@ -16,93 +16,112 @@ To contribute to the cosmos project:
 #. Link your issue to the pull request
 #. Once developments are complete on your feature branch, request a review and it will be merged once approved.
 
+Setup local development on host machine
+---------------------------------------
 
-Using Hatch for local development
----------------------------------
+This guide will setup astronomer development on host machine, first clone the ``astronomer-cosmos`` repo and enter the repo directory:
 
-We currently use `hatch <https://github.com/pypa/hatch>`_ for building and distributing ``astronomer-cosmos``.
+.. code-block:: bash
 
-The tool can also be used for local development. The `pyproject.toml <https://github.com/astronomer/astronomer-cosmos/blob/main/pyproject.toml>`_ file currently defines a matrix of supported versions of Python and Airflow for which a user can run the tests against.
+    git clone https://github.com/astronomer/astronomer-cosmos.git
+    cd astronomer-cosmos/
 
-For instance, to run the tests using Python 3.10 and Apache Airflow 2.5, use the following:
+Then install ``airflow`` and ``astronomer-cosmos`` using python-venv:
 
 .. code-block:: bash
 
-    hatch run tests.py3.10-2.5:test-cov
+    python3 -m venv env && source env/bin/activate
+    pip3 install apache-airflow[cncf.kubernetes,openlineage]
+    pip3 install -e .[dbt-postgres,dbt-databricks]
 
-It is also possible to run the tests using all the matrix combinations, by using:
+Set airflow home to the ``dev/`` directory and disabled loading example DAGs:
 
 .. code-block:: bash
 
-    hatch run tests:test-cov
+    export AIRFLOW_HOME=$(pwd)/dev/
+    export AIRFLOW__CORE__LOAD_EXAMPLES=false
 
-The integration tests rely on Postgres. It is possible to host Postgres by using Docker, for example:
+Then, run airflow in standalone mode, command below will create a new user (if not exist) and run necessary airflow component (webserver, scheduler and triggerer):
+
+    By default airflow will use sqlite as database, you can overwrite this by set variable ``AIRFLOW__DATABASE__SQL_ALCHEMY_CONN`` to the sql connection string.
 
 .. code-block:: bash
 
-    docker run --name postgres -p 5432:5432 -p 5433:5433 -e POSTGRES_PASSWORD=postgres postgres
+    airflow standalone
 
-To run the integration tests for the first time, use:
+Once the airflow is up, you can access the Airflow UI at ``http://localhost:8080``.
 
-.. code-block:: bash
+    Note: whenever you want to start the development server, you need to activate the ``virtualenv`` and set the ``environment variables``
 
-    export AIRFLOW_HOME=`pwd`
-    export AIRFLOW_CONN_AIRFLOW_DB=postgres://postgres:[email protected]:5432/postgres
-    hatch run tests.py3.8-2.5:test-integration-setup
-    hatch run tests.py3.8-2.5:test-integration
+Using Docker Compose for local development
+--------------------------------------------
 
-If testing for the same Airflow and Python version, next runs of the integration tests can be:
+It is also possible to just build the development environment using docker compose
+
+To launch a local sandbox with docker compose, first clone the ``astronomer-cosmos`` repo and enter the repo directory:
 
 .. code-block:: bash
 
-    hatch run tests.py3.8-2.5:test-integration
+    git clone https://github.com/astronomer/astronomer-cosmos.git
+    cd astronomer-cosmos/
+
+To prevent permission error on **Linux**, you must create dags, logs, and plugins folders and change owner to the user ``astro`` with the user ID 50000. To do this, run the following command:
 
 .. code-block:: bash
 
-    docker run --name postgres -p 5432:5432 -p 5433:5433 -e POSTGRES_PASSWORD=postgres postgres
+    mkdir -p dev/dags dev/logs dev/plugins
+    sudo chown 50000:50000 -R dev/dags dev/logs dev/plugins
 
-To run the integration tests for the first time, use:
+Then, run the docker compose command:
 
 .. code-block:: bash
 
-    export AIRFLOW_HOME=`pwd`
-    export AIRFLOW_CONN_AIRFLOW_DB=postgres://postgres:[email protected]:5432/postgres
-    hatch run tests.py3.8-2.5:test-integration-setup
-    hatch run tests.py3.8-2.5:test-integration
+    docker compose -f dev/docker-compose.yaml up -d --build
 
-If testing for the same Airflow and Python version, next runs of the integration tests can be:
+Once the sandbox is up, you can access the Airflow UI at ``http://localhost:8080``.
 
-.. code-block:: bash
+Testing application with hatch
+------------------------------
 
-    hatch run tests.py3.8-2.5:test-integration
+We currently use `hatch <https://github.com/pypa/hatch>`_ for building and distributing ``astronomer-cosmos``.
 
+The tool can also be used for local development. The `pyproject.toml <https://github.com/astronomer/astronomer-cosmos/blob/main/pyproject.toml>`_ file currently defines a matrix of supported versions of Python and Airflow for which a user can run the tests against.
 
-Using Docker Compose for local development
-------------------------------------------
+For instance, to run the tests using Python 3.10 and Apache Airflow 2.5, use the following:
 
-It is also possible to just build the development environment using docker compose
+.. code-block:: bash
+
+    hatch run tests.py3.10-2.5:test-cov
 
+It is also possible to run the tests using all the matrix combinations, by using:
+
+.. code-block:: bash
 
-Local Sandbox
-+++++++++++++
+    hatch run tests:test-cov
 
-To launch a local sandbox with docker compose, first clone the ``astronomer-cosmos`` repo:
+The integration tests rely on Postgres. It is possible to host Postgres by using Docker, for example:
 
 .. code-block:: bash
 
-    git clone https://github.com/astronomer/astronomer-cosmos.git
+    docker run --name postgres -p 5432:5432 -p 5433:5433 -e POSTGRES_PASSWORD=postgres postgres
 
-Then, run the following command from the ``astronomer-cosmos`` directory:
+To run the integration tests for the first time, use:
 
 .. code-block:: bash
 
-    docker compose -f dev/docker-compose.yaml up -d --build
+    export AIRFLOW_HOME=`pwd`
+    export AIRFLOW_CONN_AIRFLOW_DB=postgres://postgres:[email protected]:5432/postgres
+    hatch run tests.py3.8-2.5:test-integration-setup
+    hatch run tests.py3.8-2.5:test-integration
 
-Once the sandbox is up, you can access the Airflow UI at ``http://localhost:8080``.
+If testing for the same Airflow and Python version, next runs of the integration tests can be:
 
+.. code-block:: bash
+
+    hatch run tests.py3.8-2.5:test-integration
 
 Pre-Commit
-++++++++++
+----------
 
 We use pre-commit to run a number of checks on the code before committing. To install pre-commit, run: