Python Web Server

python-web-server.yaml

name: Python Web Server

# this example deploys a very simple python web server

services:
- type:           vanilla-bash-server
  name:           My Bash Web Server VM
  brooklyn.config:
    install.command: |
      # install python if not present
      which python || \
        { apt-get update && apt-get install python ; } || \
        { yum update && yum install python ; } || \
        { echo WARNING: cannot install python && exit 1 ; }

    customize.command: |
      # create the web page to serve
      cat > index.html << EOF
      
      Hello world.
      <p>
      I am ${ENTITY_INFO}, ${MESSAGE:-an AMP sample}.
      <p>
      Created at: `date`
      <p>
      I am running at ${HOSTNAME}, with on-box IP configuration:
      <pre>
      `ifconfig | grep inet`
      </pre>
      
      EOF

    launch.command: |
      # launch in background (ensuring no streams open), and record PID to file
      nohup python -m SimpleHTTPServer ${PORT:-8020} < /dev/null > output.txt 2>&1 &
      echo $! > ${PID_FILE:-pid.txt}
      sleep 5
      ps -p `cat ${PID_FILE:-pid.txt}`
      if [ $? -ne 0 ] ; then
        cat output.txt
        echo WARNING: python web server not running
        exit 1
      fi
      
    shell.env:
      HOSTNAME:     $brooklyn:attributeWhenReady("host.name")
      PORT:         $brooklyn:config("my.app.port")
      ENTITY_INFO:  $brooklyn:component("this", "")
      MESSAGE:      $brooklyn:config("my.message")
      
    # custom 
    my.app.port:  8020
    my.message:   "good to meet you"
  
  brooklyn.enrichers:
  # publish the URL as a sensor; the GUI will pick this up (main.uri)
  - type: org.apache.brooklyn.enricher.stock.Transformer
    brooklyn.config:
      uniqueTag: url-generator
      enricher.sourceSensor: host.name
      # use the definition from Attributes class, as it has a RendererHint so GUI makes it a link
      enricher.targetSensor: $brooklyn:sensor("org.apache.brooklyn.core.entity.Attributes", "main.uri")
      enricher.targetValue: 
        $brooklyn:formatString:
        - "http://%s:%s/" 
        - $brooklyn:attributeWhenReady("host.name")
        - $brooklyn:config("my.app.port")

location: localhost