netconf-pnp-simulator: convenient TLS and SSH configuration

- Simple SSH and TLS configuration. Instead of specific Netopeer2
  XML configuration files, the user only needs to provide:
  For SSH: id_XXX.pub
  For TLS: server_key.pem, server_cert.pem, and ca.pem

- SSH and TLS can be reconfigured at runtime by running
  /opt/bin/reconfigure-ssh.sh and /opt/bin/reconfigure-tls.sh respectively

- Improved log readability by using zlog (on C applications) and loguru
  for Python

See the updated documentation under ../docs for more information.

Issue-ID: INT-1516
Change-Id: I21052d2524f0610c6197875a544113cce1a02787
Signed-off-by: ebo <eliezio.oliveira@est.tech>

2 files changed, 116 insertions, 63 deletions

diff --git a/test/mocks/netconf-pnp-simulator/docs/README.md b/test/mocks/netconf-pnp-simulator/docs/README.md
deleted file mode 100644
index 8aa24504f..000000000
--- a/test/mocks/netconf-pnp-simulator/docs/README.md
+++ /dev/null
@@ -1,63 +0,0 @@
-# NETCONF Plug-and-Play Simulator
-
-[![GitHub Tag][gh-tag-badge]]()
-[![Docker Automated Build][dockerhub-badge]][dockerhub]
-
-## Overview
-
-This project builds a modular engine that allows the creation of NETCONF-enabled devices simulators,
-either physical (PNF) and virtual (VNF).
-
-Basically it's a docker container running Sysrepo and Netopeer2 servers enhanced with a plugger script that, at
-start-time, performs the following actions:
-
-1. Configures TLS and SSH secure accesses to the Netopeer2 server;
-2. Installs multiple YANG models into sysrepo datastore;
-3. Launches the corresponding subscriber applications.
-
-The picture below unveils the architecture of this solution.
-
-![Architecture](images/Architecture.png)
-
-A YANG module contains the following files:
-
-| Filename | Purpose
-| -------- | -------
-|`model.yang` | The YANG model specified according to [RFC-6020][yang-rfc]. Alternatively, you can use your model's name as a basename for this file. Example: `mynetconf.yang`.
-|`data.json` or `data.xml` | An optional data file used to initialize your model.
-|`subscriber.py` | The Python 3 application that implements the behavioral aspects of the YANG model.
-|`requirements.txt` | [Optional] Additional Python packages specified in the [Requirements File Format][py-requirements].
-
-## Application
-
-The `subscriber` is free to implement any wanted passive or active behaviour:
-
-**Passive Behaviour**: The subscriber will receive an event for each modification externally applied to the YANG model.
-
-**Active Behaviour**: At any point in time the subscriber can proactively change its own YANG model.
-
-## Runtime Configuration
-
-### Customizing TLS and SSH accesses
-
-The distributed docker image comes with a sample configuration for TLS and SSH, that can be found at
-`/config/tls` and `/home/netconf/.ssh` directories respectively. The user can replace one or both configurations
-by mounting a custom directory under the respective TLS or SSH mounting point.
-
-### Python Virtual Environment Support
-
-Python programs usually use additional packages not included in the standard Python distribution,
-like the `requests` package, for example.
-We support this scenario by creating isolated Python environments for each custom-provided module whenever
-a `requirements.txt` file is present in the module directory.
-
-## Example Module
-
-The directory `examples/mynetconf` contains an example YANG model and its subscriber along with a
-Docker Compose configuration file to launch a basic simulator.
-
-[dockerhub]:                  https://hub.docker.com/r/blueonap/netconf-pnp-simulator/
-[dockerhub-badge]:            https://img.shields.io/docker/cloud/automated/blueonap/netconf-pnp-simulator
-[gh-tag-badge]:               https://img.shields.io/github/v/tag/blue-onap/netconf-pnp-simulator?label=Release
-[py-requirements]:            https://pip.pypa.io/en/stable/reference/pip_install/#requirements-file-format
-[yang-rfc]:                   https://tools.ietf.org/html/rfc6020
diff --git a/test/mocks/netconf-pnp-simulator/docs/README.rst b/test/mocks/netconf-pnp-simulator/docs/README.rst
new file mode 100644
index 000000000..452827970
--- /dev/null
+++ b/test/mocks/netconf-pnp-simulator/docs/README.rst
@@ -0,0 +1,116 @@
+NETCONF Plug-and-Play Simulator
+===============================
+
+.. sectnum::
+
+.. _py-requirements: https://pip.pypa.io/en/stable/reference/pip_install/#requirements-file-format
+.. _yang-rfc: https://tools.ietf.org/html/rfc6020
+
+|ci-badge| |release-badge| |docker-badge|
+
+.. |ci-badge| image:: https://github.com/blue-onap/netconf-pnp-simulator/workflows/CI/badge.svg
+   :alt: CI
+.. |release-badge| image:: https://img.shields.io/github/v/tag/blue-onap/netconf-pnp-simulator?label=Release
+   :alt: GitHub tag
+.. |docker-badge| image:: https://img.shields.io/badge/docker%20registry-Quay.io-red
+   :target: https://quay.io/repository/blue-onap/netconf-pnp-simulator?tab=tags
+
+Overview
+--------
+
+This project builds a modular engine that allows the creation of NETCONF-enabled devices simulators,
+either physical (PNF), virtual (VNF), or cloud-native (CNF)
+
+Simply put, it's a docker container running Sysrepo and Netopeer2 servers enhanced with a plugger script that
+performs the following actions at start-time:
+
+1. Configures TLS and SSH secure accesses to the Netopeer2 server;
+2. Installs multiple YANG models into sysrepo datastore;
+3. Launches the corresponding subscriber applications.
+
+The picture below unveils the architecture of this solution.
+
+.. image:: images/Architecture.png
+   :width: 511px
+
+A YANG module contains the following files:
+
+.. list-table::
+   :widths: 10 50
+   :header-rows: 1
+
+   * - Filename
+     - Purpose
+   * - ``model.yang``
+     - The YANG model specified according to `RFC-6020 <yang-rfc_>`_ and named after the module's name, e.g., *mynetconf.yang*.
+   * - ``startup.json`` or ``startup.xml``
+     - An optional data file with the initial values of the model. Both JSON and XML formats are supported.
+   * - ``subscriber.py``
+     - The Python 3 application that implements the behavioral aspects of the YANG model.
+   * - ``requirements.txt``
+     - [Optional] Lists the additional Python packages required by the application, specified in the `Requirements File Format <py-requirements_>`_.
+
+Application
+-----------
+
+The ``subscriber.py`` application can implement any wanted passive or active behaviour:
+
+**Passive Behaviour**: The subscriber will receive an event for each modification externally applied to the YANG model.
+
+**Active Behaviour**: At any point in time the subscriber can proactively change its own YANG model.
+
+Runtime Configuration
+---------------------
+
+Customizing TLS and SSH accesses
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The distributed docker image comes with a sample configuration for TLS and SSH, that can be found at
+``/config/tls`` and ``/config/ssh`` directories respectively. The user can replace one or both configurations
+by mounting a custom directory under the respective TLS or SSH mounting point.
+
+TLS Configuration
+^^^^^^^^^^^^^^^^^
+
+You need to provide the following PEM files under ``/config/tls``:
+
+.. list-table::
+   :widths: 10 50
+   :header-rows: 1
+
+   * - File
+     - Contents
+   * - ``server_key.pem``
+     - The server's private key in plain (*not* protected by a passphrase).
+   * - ``server_cert.pem``
+     - The corresponding server's X.509v3 certificate.
+   * - ``ca.pem``
+     - The Certificate Authority (CA) certificate.
+
+.. TIP:: You can reload the configuration at runtime by running ``docker exec <CONTAINER NAME or ID> /opt/bin/reconfigure-tls.sh``
+
+SSH Configuration
+^^^^^^^^^^^^^^^^^
+
+For the SSH connection, you need to provide the public SSH key in one of these 3 files under ``/config/ssh``
+in order of preference:
+
+- ``id_ecdsa.pub``; or
+- ``id_dsa.pub``; or
+- ``id_rsa.pub``
+
+.. TIP:: You can reload the configuration at runtime by running ``docker exec <CONTAINER NAME or ID> /opt/bin/reconfigure-ssh.sh``
+
+Python Virtual Environment Support
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Python programs usually use additional packages not included in the standard Python distribution,
+like the ``requests`` package, for example.
+We support this scenario by creating isolated Python environments for each custom-provided module whenever
+a ``requirements.txt`` file is present in the module directory.
+
+Example Module
+--------------
+
+The directory ``examples/mynetconf`` contains an example YANG model and its subscriber along with a
+Docker Compose configuration file to launch a basic simulator.