Add pmon daemons python3 build support (#6176)

**- Why I did it**

python2 is end of life and SONiC is going to support python3. This PR is going to support:

1. Build pmon daemons with python3
2. Install and run python3 version pmon daemons

**- How I did it**

1. Change pmon daemons make files to build bothe python2 and python3 whl
2. Change docker-platform-monitor make files to install both python2 and python3 whl
3. Change pmon docker startup files to start pmon daemons according to the supported platform API version

dockers/docker-platform-monitor/docker_init.sh

@@ -5,45 +5,102 @@ mkdir -p /etc/supervisor/conf.d/
 
 SENSORS_CONF_FILE="/usr/share/sonic/platform/sensors.conf"
 FANCONTROL_CONF_FILE="/usr/share/sonic/platform/fancontrol"
+
+SUPERVISOR_CONF_TEMPLATE="/usr/share/sonic/templates/docker-pmon.supervisord.conf.j2"
+SUPERVISOR_CONF_FILE="/etc/supervisor/conf.d/supervisord.conf"
+PMON_DAEMON_CONTROL_FILE="/usr/share/sonic/platform/pmon_daemon_control.json"
 MODULAR_CHASSISDB_CONF_FILE="/usr/share/sonic/platform/chassisdb.conf"
 
 HAVE_SENSORS_CONF=0
 HAVE_FANCONTROL_CONF=0
 IS_MODULAR_CHASSIS=0
+# Default use python2 version
+SONIC_PLATFORM_API_PYTHON_VERSION=2
+
+declare -r EXIT_SUCCESS="0"
+
+if [ "${RUNTIME_OWNER}" == "" ]; then
+    RUNTIME_OWNER="kube"
+fi
+
+CTR_SCRIPT="/usr/share/sonic/scripts/container_startup.py"
+if test -f ${CTR_SCRIPT}
+then
+    ${CTR_SCRIPT} -f pmon -o ${RUNTIME_OWNER} -v ${IMAGE_VERSION}
+fi
+
+mkdir -p /var/sonic
+echo "# Config files managed by sonic-config-engine" > /var/sonic/config_status
+
+# If this platform has synchronization script, run it
+if [ -e /usr/share/sonic/platform/platform_wait ]; then
+    /usr/share/sonic/platform/platform_wait
+    EXIT_CODE="$?"
+    if [ "${EXIT_CODE}" != "${EXIT_SUCCESS}" ]; then
+        exit "${EXIT_CODE}"
+    fi
+fi
+
+# If the Python 2 sonic-platform package is not installed, try to install it
+python2 -c "import sonic_platform" > /dev/null 2>&1 || pip2 show sonic-platform > /dev/null 2>&1
+if [ $? -ne 0 ]; then
+    SONIC_PLATFORM_WHEEL="/usr/share/sonic/platform/sonic_platform-1.0-py2-none-any.whl"
+    echo "sonic-platform package not installed, attempting to install..."
+    if [ -e ${SONIC_PLATFORM_WHEEL} ]; then
+       pip2 install ${SONIC_PLATFORM_WHEEL}
+       if [ $? -eq 0 ]; then
+          echo "Successfully installed ${SONIC_PLATFORM_WHEEL}"
+       else
+          echo "Error: Failed to install ${SONIC_PLATFORM_WHEEL}"
+       fi
+    else
+       echo "Error: Unable to locate ${SONIC_PLATFORM_WHEEL}"
+    fi
+fi
+
+# If the Python 3 sonic-platform package is not installed, try to install it
+python3 -c "import sonic_platform" > /dev/null 2>&1 || pip3 show sonic-platform > /dev/null 2>&1
+if [ $? -ne 0 ]; then
+    SONIC_PLATFORM_WHEEL="/usr/share/sonic/platform/sonic_platform-1.0-py3-none-any.whl"
+    echo "sonic-platform package not installed, attempting to install..."
+    if [ -e ${SONIC_PLATFORM_WHEEL} ]; then
+       pip3 install ${SONIC_PLATFORM_WHEEL}
+       if [ $? -eq 0 ]; then
+          echo "Successfully installed ${SONIC_PLATFORM_WHEEL}"
+          SONIC_PLATFORM_API_PYTHON_VERSION=3
+       else
+          echo "Error: Failed to install ${SONIC_PLATFORM_WHEEL}"
+       fi
+    else
+       echo "Error: Unable to locate ${SONIC_PLATFORM_WHEEL}"
+    fi
+else
+    SONIC_PLATFORM_API_PYTHON_VERSION=3
+fi
 
 if [ -e $SENSORS_CONF_FILE ]; then
     HAVE_SENSORS_CONF=1
+    mkdir -p /etc/sensors.d
+    /bin/cp -f $SENSORS_CONF_FILE /etc/sensors.d/
 fi
 
 if [ -e $FANCONTROL_CONF_FILE ]; then
     HAVE_FANCONTROL_CONF=1
+    rm -f /var/run/fancontrol.pid
+    /bin/cp -f $FANCONTROL_CONF_FILE /etc/
 fi
 
 if [ -e $MODULAR_CHASSISDB_CONF_FILE ]; then
     IS_MODULAR_CHASSIS=1
 fi
 
-confvar="{\"HAVE_SENSORS_CONF\":$HAVE_SENSORS_CONF, \"HAVE_FANCONTROL_CONF\":$HAVE_FANCONTROL_CONF, \"IS_MODULAR_CHASSIS\":$IS_MODULAR_CHASSIS}"
+confvar="{\"HAVE_SENSORS_CONF\":$HAVE_SENSORS_CONF, \"HAVE_FANCONTROL_CONF\":$HAVE_FANCONTROL_CONF, \"API_VERSION\":$SONIC_PLATFORM_API_PYTHON_VERSION, \"IS_MODULAR_CHASSIS\":$IS_MODULAR_CHASSIS}"
 
-if [ -e /usr/share/sonic/platform/pmon_daemon_control.json ];
+if [ -e $PMON_DAEMON_CONTROL_FILE ];
 then
-    sonic-cfggen -j /usr/share/sonic/platform/pmon_daemon_control.json -a "$confvar" -t /usr/share/sonic/templates/docker-pmon.supervisord.conf.j2 > /etc/supervisor/conf.d/supervisord.conf
+    sonic-cfggen -j $PMON_DAEMON_CONTROL_FILE -a "$confvar" -t $SUPERVISOR_CONF_TEMPLATE > $SUPERVISOR_CONF_FILE
 else
-    sonic-cfggen -a "$confvar" -t /usr/share/sonic/templates/docker-pmon.supervisord.conf.j2 > /etc/supervisor/conf.d/supervisord.conf
-fi
-
-# If this platform has an lm-sensors config file, copy it to its proper place
-if [ $HAVE_SENSORS_CONF -eq 1 ]; then
-    mkdir -p /etc/sensors.d
-    /bin/cp -f $SENSORS_CONF_FILE /etc/sensors.d/
-fi
-
-# If this platform has a fancontrol config file, copy it to its proper place
-if [ $HAVE_FANCONTROL_CONF -eq 1 ]; then
-    # Remove stale pid file if it exists
-    rm -f /var/run/fancontrol.pid
-
-    /bin/cp -f $FANCONTROL_CONF_FILE /etc/
+    sonic-cfggen -a "$confvar" -t $SUPERVISOR_CONF_TEMPLATE > $SUPERVISOR_CONF_FILE
 fi
 
 exec /usr/local/bin/supervisord