Save event driven for the future, requires

moby/swarmkit#491

app/event.py

@@ -0,0 +1,163 @@
+import os
+import logging
+import ConfigParser
+from Queue import Queue
+from threading import Thread
+
+import click
+import boto3
+import docker
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger("controller")
+
+
+def getContainer(container_id, docker_client):
+    return docker_client.containers.get(container_id=container_id)
+
+
+def getPorts(container):
+    ports = container.attrs.get("NetworkSettings").get("Ports")
+    # EG: (u'12312/tcp', [{u'HostIp': u'0.0.0.0', u'HostPort': u'1234'}])
+
+    for mappings in ports.values():
+        # EG: [{u'HostPort': u'1234', u'HostIp': u'0.0.0.0'}]
+        # Check if the port is mapped
+        if mappings is not None:
+            for mapping in mappings:
+                yield mapping
+
+
+def createELBPort(port, elb_name, elb_client):
+    elb_client.create_load_balancer_listeners(
+        LoadBalancerName=elb_name,
+        Listeners=[
+            {
+                'Protocol': 'TCP',
+                'LoadBalancerPort': port,
+                'InstanceProtocol': 'TCP',
+                'InstancePort': port,
+            },
+        ]
+    )
+
+
+def destroyELBPort(port, elb_name, elb_client):
+    elb_client.delete_load_balancer_listeners(
+        LoadBalancerName=elb_name,
+        LoadBalancerPorts=[
+            port,
+        ]
+    )
+
+
+def worker(worker_id, work_queue, elb_client, elb_config, docker_client):
+    # Set debug format to log worker id
+    logger.debug("Starting worker {}".format(worker_id))
+    try:
+        while True:
+            event = work_queue.get()
+
+            container_id = event.get("id")
+            container = docker_client.containers.get(container_id=container_id)
+
+            for mapping in getPorts(container):
+                logger.debug("Container: {} Action: {} Mapping: {}".format(
+                    container,
+                    event.get("Action"),
+                    mapping,
+                ))
+
+                elb_name = elb_config.get('main', mapping.get("HostIp"))
+                port = mapping.get("HostPort")
+
+                if event.get("Action") == "start":
+                    logger.info("{}:AWS will add {} to {}".format(
+                            worker_id, port,
+                            elb_name
+                        )
+                    )
+                    createELBPort(int(port), elb_name, elb_client)
+
+                elif event.get("Action") == "kill":
+                    logger.info("{}:AWS will remove {} to {}".format(
+                            worker_id, port,
+                            elb_name
+                        )
+                    )
+                    destroyELBPort(int(port), elb_name, elb_client)
+            work_queue.task_done()
+    except Exception as e:
+        logger.error(e)
+        os._exit(1)
+        pass
+
+
+@click.command()
+@click.option(
+    '--workers',
+    default=2,
+    envvar='WORKERS',
+    help='Number of worker threads.'
+    )
+@click.option(
+    '--debug',
+    default=False,
+    envvar='DEBUG',
+    help='Enable or disable debug loggin.'
+    )
+@click.option(
+    '--region',
+    default='',
+    envvar='AWS_REGION',
+    help='AWS Region to look for the ELB.'
+    )
+def run(workers, debug, region):
+    if debug in ["True", "true", "1"]:
+        logger.info("Enabling debug loggin")
+        logger.setLevel(level=logging.DEBUG)
+        logger.debug("Debug loggin enabled")
+
+    elb_config = ConfigParser.RawConfigParser()
+    elb_config.read(
+        os.getenv('ELB_CONFIG', '/var/lib/docker/swarm/config.cfg')
+    )
+
+    docker_client = docker.from_env()
+    elb_client = boto3.client('elb', region_name=region)
+    work_queue = Queue()
+
+    for i in range(workers):
+        t = Thread(
+                target=worker, args=(
+                    i,
+                    work_queue,
+                    elb_client,
+                    elb_config,
+                    docker_client
+                )
+            )
+        t.daemon = True
+        t.start()
+
+    filters = {
+        'Type': 'container'
+    }
+
+    for event in docker_client.events(decode=True, filters=filters):
+        logger.debug(
+            "Action:{} Image:{}".format(event.get("Action"), event.get("id"))
+        )
+        action = event.get("Action")
+        if action in ["start", "kill"]:
+            work_queue.put(
+                event
+            )
+        else:
+            logger.debug("It did not match any 'start' or 'kill'")
+
+    work_queue.join()  # block until all tasks are done
+
+
+if __name__ == '__main__':
+    run()