[docker_deamon] [ecs] try to build the ecs introspection url.

[docker_deamon] [ecs] add the ability to add the ecs (docker) gateway.

[docker_daemon] [ecs] no need to raise, implicit in json() call.

[docker_deamon] [ecs] get docker gw from /proc.

checks.d/docker_daemon.py

@@ -111,6 +111,8 @@
 FILTERED = "filtered"
 IMAGE = "image"
 
+ECS_INTROSPECT_DEFAULT_PORT = 51678
+
 
 def get_filters(include, exclude):
     # The reasoning is to check exclude first, so we can skip if there is no exclude
@@ -158,6 +160,8 @@ def init(self):
             # Just needs to be done once
             self.docker_util = DockerUtil()
             self.docker_client = self.docker_util.client
+            self.docker_gateway = DockerUtil.get_gateway()
+
             if self.is_k8s():
                 self.kubeutil = KubeUtil()
             self._mountpoints = self.docker_util.get_mountpoints(CGROUP_METRICS)
@@ -427,13 +431,24 @@ def refresh_ecs_tags(self):
         ip = ecs_config.get('NetworkSettings', {}).get('IPAddress')
         ports = ecs_config.get('NetworkSettings', {}).get('Ports')
         port = ports.keys()[0].split('/')[0] if ports else None
+        if not ip and DockerUtil.is_dockerized():
+            if self.docker_gateway:
+                ip = self.docker_gateway
+                port = ECS_INTROSPECT_DEFAULT_PORT
+        elif not ip:
+            ip = "localhost"
+            port = ECS_INTROSPECT_DEFAULT_PORT
+
         ecs_tags = {}
-        if ip and port:
-            tasks = requests.get('http://%s:%s/v1/tasks' % (ip, port)).json()
-            for task in tasks.get('Tasks', []):
-                for container in task.get('Containers', []):
-                    tags = ['task_name:%s' % task['Family'], 'task_version:%s' % task['Version']]
-                    ecs_tags[container['DockerId']] = tags
+        try:
+            if ip and port:
+                tasks = requests.get('http://%s:%s/v1/tasks' % (ip, port)).json()
+                for task in tasks.get('Tasks', []):
+                    for container in task.get('Containers', []):
+                        tags = ['task_name:%s' % task['Family'], 'task_version:%s' % task['Version']]
+                        ecs_tags[container['DockerId']] = tags
+        except requests.exceptions.HTTPError as e:
+            self.log.warning("Unable to collect ECS task names: %s" % e)
 
         self.ecs_tags = ecs_tags
 

utils/dockerutil.py

@@ -6,6 +6,8 @@
 import logging
 import os
 import time
+import socket
+import struct
 
 # 3rd party
 from docker import Client
@@ -34,6 +36,7 @@ class DockerUtil:
     __metaclass__ = Singleton
 
     DEFAULT_SETTINGS = {"version": DEFAULT_VERSION}
+    DEFAULT_PROCFS_GW_PATH = "proc/net/route"
 
     def __init__(self, **kwargs):
         self._docker_root = None
@@ -113,6 +116,22 @@ def get_events(self):
 
         return self.events, should_reload_conf
 
+    @classmethod
+    def get_gateway(cls, proc_prefix=""):
+        procfs_route = os.path.join("/", proc_prefix, cls.DEFAULT_PROCFS_GW_PATH)
+
+        try:
+            with open(procfs_route) as f:
+                for line in f.readlines():
+                    fields = line.strip().split()
+                    if fields[1] == '00000000':
+                        return socket.inet_ntoa(struct.pack('<L', int(fields[2], 16)))
+        except IOError, e:
+            log.error('Unable to open {}: %s'.format(procfs_route), e)
+
+        return None
+
+
     def get_hostname(self):
         """Return the `Name` param from `docker info` to use as the hostname"""
         try: