EL7 migration from python 2 to python 3

.circleci/config.yml

@@ -13,6 +13,8 @@ jobs:
       - restore_cache:
           key: v2-dependency-cache-{{ checksum "st2/requirements.txt" }}
       - run: sudo apt install python-dev
+      - run: sudo apt install libldap2-dev
+      - run: sudo apt install libsasl2-dev
       - run: make docs
       - run:
           name: Store HTML docs in workspace dir

docs/source/install/rhel7.rst

@@ -11,6 +11,11 @@ System Requirements
 
 Please check the :doc:`supported versions and system requirements <system_requirements>`.
 
+.. note::
+
+    |st2| on RHEL 7/CentOS 7 runs all services, actions and sensors using Python 3 **only**. It
+    does not support Python 2 actions. 
+
 Minimal Installation
 --------------------
 
@@ -34,6 +39,9 @@ you may want to tweak them according to your security practices.
     # SELINUX management tools, not available for some minimal installations
     sudo yum install -y policycoreutils-python
 
+    # SELINUX python3 rules
+    sudo yum install -y libselinux-python3
+
     # Allow network access for nginx
     sudo setsebool -P httpd_can_network_connect 1
 
@@ -73,6 +81,26 @@ Install MongoDB, and RabbitMQ:
   sudo systemctl start mongod rabbitmq-server
   sudo systemctl enable mongod rabbitmq-server
 
+The default python on CentOS/RHEL 7.x is python 2, |st2| uses python3 and requires the python3-devel package. The installation of the st2 package will automatically install python3-devel if it is available in an enabled repository. On CentOS distributions the relevant repository is typically enabled however on RHEL distributions it is provided by the rhel-7-server-optional-rpms repository (repository name dependant on RHEL distribution).
+
+Use the following command to verify that the python3-devel package is available in an enabled repository:
+
+.. code-block:: bash
+
+  sudo yum info python3-devel
+
+If it is not available, then locate the optional-rpms repository:
+
+.. code-block:: bash
+
+  sudo yum repolist disabled | grep optional | grep server
+
+Then either enable the optional repository using subscription-manager or yum-config-manager, or install python3-devel with a temporary repository enablement, e.g.:
+
+.. code-block:: bash
+
+  sudo yum install python3-devel --enablerepo <optional-server-rpm repo>
+
 Setup Repositories
 ~~~~~~~~~~~~~~~~~~
 

docs/source/install/upgrades.rst

@@ -167,6 +167,38 @@ The following sections call out the migration scripts that need to be run when u
 respective version. If you are upgrading across multiple versions, make sure you run the scripts for
 any skipped versions:
 
+v3.4
+''''
+
+*  |st2| now uses python 3 on RHEL/CentOS 7. Therefore any packs that only support python 2 will need to be upgraded to python 3.
+
+
+* If SELINUX is enabled, install the python 3 SELinux rules with:
+
+  .. sourcecode:: bash
+
+    sudo yum install -y libselinux-python3
+
+* Ensure python3-devel can be installed from an enabled repository:
+
+  * Check if python3-devel is already available in an enabled repository:
+
+  .. sourcecode:: bash
+
+    sudo yum info python3-devel
+
+  * If it is not available, then locate the name of the optional server RPMs repository:
+
+  .. sourcecode:: bash
+
+    sudo yum repolist disabled | grep optional | grep server
+
+  * Either enable the optional repository using subscription-manager or yum-config-manager, or install python3-devel with a temporary repository enablement, e.g.:
+
+  .. sourcecode:: bash
+
+    sudo yum install python3-devel --enablerepo <optional-server-rpm repo>
+
 
 v3.3
 ''''

docs/source/packs.rst

@@ -293,13 +293,13 @@ Python versions in Pack Python Virtual Environment
 
 When installing a pack, a Python virtual environment is created using the Python binary defined by
 the ``actionrunner.python_binary`` config option. By default, the same binary which is
-used by all the |st2| components and services is used for pack virtual environments. On CentOS/RHEL 7 and Ubuntu 16.04 the Python binary currently used is Python 2.7, on all other distributions Python 3 is used.
+used by all the |st2| components and services is used for pack virtual environments. On Ubuntu 16.04 the Python binary currently used is Python 2.7, on all other distributions Python 3 is used.
 
 .. warning ::
 
    Python 2 support will be dropped from |st2| in future releases. Please consider updating any Python 2 only packs to work with Python 3.
 
-On CentOS/RHEL 7 and Ubuntu 16.04 if you want to use Python 3 for running your pack Python actions, you can do that by passing  the
+On Ubuntu 16.04 if you want to use Python 3 for running your pack Python actions, you can do that by passing the
 ``--python3`` flag to the ``st2 pack install`` command (e.g. ``st2 pack install libcloud
 --python3``).
 

docs/source/upgrade_notes.rst

@@ -3,6 +3,13 @@
 Upgrade Notes
 =============
 
+.. _ref-upgrade-notes-v3-4:
+
+|st2| v3.4
+-------------
+
+* RHEL/CentOS 7.x ST2 distributions now uses python version 3 for ST2 and all packs, therefore any packs that only support python 2 will need to be migrated to python 3.
+
 .. _ref-upgrade-notes-v3-3:
 
 |st2| v3.3