sonic-buildimage/files/build_templates/docker_image_ctl.j2

#!/bin/bash

function getMountPoint()
{
    echo $1 |  python -c "import sys, json, os; mnts = [x for x in json.load(sys.stdin)[0]['Mounts'] if x['Destination'] == '/usr/share/sonic/hwsku']; print '' if len(mnts) == 0 else os.path.basename(mnts[0]['Source'])" 2>/dev/null
}

function postStartAction()
{
{%- if docker_container_name != "database" %}
    :
{%- else %}
    while true; do
        if [[ "$(docker exec -i database redis-cli ping)" =~ PONG.* ]]; then
            break
        fi
        sleep 1
    done
{%- endif %}
{%- if docker_container_name == "snmp" %}
    docker exec -i database redis-cli -n 6 HSET 'DEVICE_METADATA|localhost' chassis_serial_number $(decode-syseeprom -s)
{%- endif %}
}

# Obtain our platform as we will mount directories with these names in each docker
PLATFORM=`sonic-cfggen -v platform`

{%- if docker_container_name == "database" %}
# Don't mount HWSKU in {{docker_container_name}} container.
HWSKU=""
{%- else %}
# Obtain our HWSKU as we will mount directories with these names in each docker
HWSKU=`sonic-cfggen -d -v 'DEVICE_METADATA["localhost"]["hwsku"]'`
{%- endif %}

start() {
    DOCKERCHECK=`docker inspect --type container {{docker_container_name}} 2>/dev/null`
    if [ "$?" -eq "0" ]; then
        DOCKERMOUNT=`getMountPoint "$DOCKERCHECK"`
        if [ "$DOCKERMOUNT" == "$HWSKU" ]; then
            echo "Starting existing {{docker_container_name}} container with HWSKU $HWSKU"
            docker start {{docker_container_name}}
            postStartAction
            exit 0
        fi

        # docker created with a different HWSKU, remove and recreate
        echo "Removing obsolete {{docker_container_name}} container with HWSKU $DOCKERMOUNT"
        docker rm {{docker_container_name}}
    fi

{%- if docker_container_name == "database" %}
    echo "Starting new {{docker_container_name}} container"
{%- else %}
    echo "Starting new {{docker_container_name}} container with HWSKU $HWSKU"
{%- endif %}
    docker run -d {{docker_image_run_opt}} \
{%- if '--log-driver=json-file' in docker_image_run_opt or '--log-driver' not in docker_image_run_opt %}
        --log-opt max-size=2M --log-opt max-file=5 \
{%- endif %}
        -v /var/run/redis:/var/run/redis:rw \
        -v /usr/share/sonic/device/$PLATFORM:/usr/share/sonic/platform:ro \
{%- if docker_container_name != "database" %}
        -v /usr/share/sonic/device/$PLATFORM/$HWSKU:/usr/share/sonic/hwsku:ro \
{%- endif %}
        --tmpfs /tmp \
        --tmpfs /var/tmp \
        --name={{docker_container_name}} {{docker_image_name}}:latest

    postStartAction
}

attach() {
    docker attach --no-stdin {{docker_container_name}}
}

stop() {
    docker stop {{docker_container_name}}
}

case "$1" in
    start|stop|attach)
        $1
        ;;
    *)
        echo "Usage: $0 {start|stop|attach}"
        exit 1
        ;;
esac