Update to new ambassador code

configure-ambassadors.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+
+import os
+import subprocess
+import sys
+import yaml
+
+stack = yaml.load(open(sys.argv[1]))
+
+project_name = os.path.basename(os.path.realpath("."))
+
+# Get all services and backends in our compose application
+containers_data = subprocess.check_output([
+    "docker", "ps",
+    "--filter", "label=com.docker.compose.project={}".format(project_name),
+    "--format", '{{ .ID }} '
+                '{{ .Label "com.docker.compose.service" }} '
+                '{{ .Ports }}',
+])
+
+# Build list of backends
+frontend_ports = dict()
+backends = dict()
+for container in containers_data.split('\n'):
+    if not container:
+        continue
+    # TODO: support services with multiple ports!
+    container_id, service_name, port = container.split(' ')
+    if not port:
+        continue
+    backend, frontend = port.split("->")
+    backend_addr, backend_port = backend.split(':')
+    frontend_port, frontend_proto = frontend.split('/')
+    # TODO: deal with udp (mostly skip it?)
+    assert frontend_proto == "tcp"
+    # TODO: check inconsistencies between port mappings
+    frontend_ports[service_name] = frontend_port
+    if service_name not in backends:
+        backends[service_name] = []
+    backends[service_name].append((backend_addr, backend_port))
+
+# Get all existing ambassadors for this application
+ambassadors_data = subprocess.check_output([
+    "docker", "ps",
+    "--filter", "label=ambassador.project={}".format(project_name),
+    "--format", '{{ .ID }} '
+                '{{ .Label "ambassador.service" }} '
+                '{{ .Label "ambassador.bindaddr" }}',
+])
+
+# Update ambassadors
+for ambassador in ambassadors_data.split('\n'):
+    if not ambassador:
+        continue
+    ambassador_id, service_name, bind_address = ambassador.split()
+    print("Updating configuration for {}/{} -> {}:{} -> {}"
+          .format(service_name, ambassador_id,
+                  bind_address, frontend_ports[service_name],
+                  backends[service_name]))
+    command = [
+        "docker", "run", "--rm", "--volumes-from", ambassador_id,
+        "jpetazzo/hamba", "reconfigure",
+        "{}:{}".format(bind_address, frontend_ports[service_name])
+    ]
+    for backend_addr, backend_port in backends[service_name]:
+        command.extend([backend_addr, backend_port])
+    print command
+    subprocess.check_call(command)

connect-services.py

@@ -1,73 +0,0 @@
-#!/usr/bin/env python
-
-import os
-import subprocess
-import sys
-import yaml
-
-stack = yaml.load(open(sys.argv[1]))
-
-ports = yaml.load(open("ports.yml"))
-
-project_name = os.path.basename(os.path.realpath("."))
-
-ambassadors = []
-
-service_instances = {}
-
-# Generate container names for all instances
-for service_name in stack:
-    service_instances[service_name] = []
-    n = 0
-    while True:
-        n += 1
-        try:
-            container_name = "{}_{}_{}".format(project_name, service_name, n)
-            subprocess.check_call(
-                [ "docker", "inspect", container_name ],
-                stdout=-1, stderr=-1
-            )
-            service_instances[service_name].append(container_name)
-        except subprocess.CalledProcessError:
-            break
-
-for service_name, service in stack.items():
-    extra_hosts = service.get("extra_hosts", {})
-    for link_name, link_addr in extra_hosts.items():
-        if link_name not in ports:
-            print("# Skipping link {} in service {} "
-                  "(no port mapping defined). "
-                  "Your code will probably break."
-                  .format(link, service_name))
-            continue
-        port = str(ports[link_name])
-        endpoints = []
-        for container_name in service_instances[link_name]:
-            endpoint = subprocess.check_output(
-                ["docker", "port", container_name, port]
-            )
-            endpoints.append(endpoint.strip())
-        for container_name in service_instances[service_name]:
-            ambassador = {}
-            ambassador["image"] = "jpetazzo/hamba"
-            ambassador["net"] = "container:"+container_name
-            command = "{}:{}".format(link_addr, port)
-            for endpoint in endpoints:
-                command = command + " {} {}".format(*endpoint.split(':'))
-            ambassador["command"] = command
-            n = len(ambassadors)
-            ambassador["name"] = "amba{}".format(n)
-            ambassadors.append(ambassador)
-
-for service_name, service in stack.items():
-    for container_name in service_instances[service_name]:
-        print("docker exec {} sh -c 'sed /^127.127/d /etc/hosts >/tmp/hosts && cat /tmp/hosts >/etc/hosts && rm /tmp/hosts'"
-              .format(container_name))
-        extra_hosts = service.get("extra_hosts", {})
-        for link_name, link_addr in extra_hosts.items():
-            print("docker exec {} sh -c 'echo {} {} >> /etc/hosts'"
-                  .format(container_name, link_addr, link_name))
-
-for amba in ambassadors:
-    print("docker run -d --name {name} --net {net} {image} {command}".format(**amba))
-

create-ambassadors.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python
+
+import os
+import subprocess
+import sys
+import yaml
+
+stack = yaml.load(open(sys.argv[1]))
+
+project_name = os.path.basename(os.path.realpath("."))
+
+# Get all services in our compose application
+containers_data = subprocess.check_output([
+    "docker", "ps",
+    "--filter", "label=com.docker.compose.project={}".format(project_name),
+    "--format", '{{ .ID }} {{ .Label "com.docker.compose.service" }}',
+])
+
+# Get all existing ambassadors for this application
+ambassadors_data = subprocess.check_output([
+    "docker", "ps",
+    "--filter", "label=ambassador.project={}".format(project_name),
+    "--format", '{{ .ID }} '
+                '{{ .Label "ambassador.container" }} '
+                '{{ .Label "ambassador.service" }}',
+])
+
+# Build a set of existing ambassadors
+ambassadors = dict()
+for ambassador in ambassadors_data.split('\n'):
+    if not ambassador:
+        continue
+    ambassador_id, container_id, linked_service = ambassador.split()
+    ambassadors[container_id, linked_service] = ambassador_id
+
+# Start the missing ambassadors
+for container in containers_data.split('\n'):
+    if not container:
+        continue
+    container_id, service_name = container.split()
+    extra_hosts = stack[service_name].get("extra_hosts", {})
+    for linked_service, bind_address in extra_hosts.items():
+        description = "Ambassador {}/{}/{}".format(
+            service_name, container_id, linked_service)
+        ambassador_id = ambassadors.get((container_id, linked_service))
+        if ambassador_id:
+            print("{} already exists: {}".format(description, ambassador_id))
+        else:
+            print("{} not found, creating it:".format(description))
+	    subprocess.check_call([
+		"docker", "run", "-d",
+		"--net", "container:{}".format(container_id),
+		"--label", "ambassador.project={}".format(project_name),
+		"--label", "ambassador.container={}".format(container_id),
+		"--label", "ambassador.service={}".format(linked_service),
+		"--label", "ambassador.bindaddr={}".format(bind_address),
+		"jpetazzo/hamba", "run"
+	    ])
+

delete-ambassadors.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+docker ps -q --filter label=ambassador.project=dockercoins | 
+xargs docker rm -f

destroy-amba.sh

@@ -1,5 +0,0 @@
-#!/bin/sh
-N=0
-while docker rm -f amba$N; do
-    N=$(($N+1))
-done