Inspect only the containers carrying the lookup label

src/processor/docker.py

@@ -26,6 +26,9 @@ class Docker(ProcessorInterface):
 
         self.parsed_object = {}
         for container in self.client.containers.list():
+            if not any(self.label in key for key in container.labels):
+                continue
+
             # Issue 32 - Docker container cannot connect to containers in different network.
             if ha_proxy_network_name not in container.attrs["NetworkSettings"]["Networks"].keys():
                 ha_proxy_network.connect(container.name)

tests/test_docker.py

@@ -105,4 +105,53 @@ def test_processor_docker():
         container2.stop()
 
 
+def test_processor_docker_ignores_unlabeled():
+    try:
+        client = docker.from_env()
+    except docker.errors.DockerException:
+        pytest.skip("There is no docker environment")
+
+    if len(client.containers.list()) > 0:
+        pytest.skip("I cannot run this test with other containers running.")
+
+    network = client.networks.create("test_processor_docker_network", driver="bridge")
+    # The most recent container is inspected first, so the labeled one defines the network to use.
+    unlabeled = client.containers.run("byjg/static-httpserver",
+                                      name="test_processor_docker_unlabeled",
+                                      detach=True,
+                                      auto_remove=True,
+                                      remove=True)
+    time.sleep(1)
+    container = client.containers.run("byjg/static-httpserver",
+                                      name="test_processor_docker_labeled",
+                                      detach=True,
+                                      auto_remove=True,
+                                      remove=True,
+                                      network=network.name,
+                                      labels={
+                                          "easyhaproxy.labeled.port": "80",
+                                          "easyhaproxy.labeled.localport": "8080",
+                                          "easyhaproxy.labeled.host": "labeled.local",
+                                      })
+    try:
+        time.sleep(1)
+
+        static = ProcessorInterface.factory(ProcessorInterface.DOCKER)
+
+        # The labeled container is served through the network it already belongs to.
+        labeled_ip = client.containers.get(container.name).attrs["NetworkSettings"]["Networks"][network.name][
+            "IPAddress"]
+        assert _get_ip_host(static.get_parsed_object(), "easyhaproxy.labeled") == labeled_ip
+
+        # The container without any label is neither inspected nor connected to the network.
+        unlabeled_networks = client.containers.get(unlabeled.name).attrs["NetworkSettings"]["Networks"]
+        assert list(unlabeled_networks.keys()) == ["bridge"]
+        assert unlabeled_networks["bridge"]["IPAddress"] not in static.get_parsed_object()
+    finally:
+        container.stop()
+        unlabeled.stop()
+        time.sleep(1)
+        network.remove()
+
+
 # test_processor_docker()