Broker changes for remote podman (tcp and ipv6)

We have encountered a couple of issues that need to be solved in order to use Broker with remote podman hosts.

  First is an issue with the ssh\-based connection to remote podman that was investigated in a previous issue. The
  solution to this from Broker's side is largely changing the connection string based on the host\_port given.

  Second is to give Broker the ability to automatically find and pass along the correct network information when
  spinning up an ipv6 container. The solution for this is to list networks, search for one that is ipv6 enabled, then
  modify the container creation arguments to pass along that network information

broker/binds/containers.py

@@ -1,8 +1,11 @@
 """A collection of classes to ease interaction with Docker and Podman libraries."""
+from broker.exceptions import UserError
+from broker.settings import settings
 
 HEADER_SIZE = 8
 STDOUT = 1
 STDERR = 2
+SSH_PORT = 22
 
 
 def demux_output(data_bytes):
@@ -79,6 +82,11 @@ def containers(self):
         """Return a list of containers on the container host."""
         return self.client.containers.list(all=True)
 
+    @property
+    def networks(self):
+        """Return a list of networks on the container host."""
+        return self.client.networks.list()
+
     def image_info(self, name):
         """Return curated information about an image on the container host."""
         if image := self.client.images.get(name):
@@ -91,6 +99,12 @@ def image_info(self, name):
 
     def create_container(self, image, command=None, **kwargs):
         """Create and return running container instance."""
+        if net_name := settings.container.network:
+            if not self.get_network_by_attrs({"name": net_name}):
+                raise UserError(
+                    f"Network '{settings.container.network}' not found on container host."
+                )
+            kwargs["networks"] = {net_name: {"NetworkId": net_name}}
         kwargs = self._sanitize_create_args(kwargs)
         return self.client.containers.create(image, command, **kwargs)
 
@@ -107,6 +121,12 @@ def pull_image(self, name):
         """Pull an image into the container host."""
         return self.client.images.pull(name)
 
+    def get_network_by_attrs(self, attr_dict):
+        """Return the first matching network that matches all attr_dict keys and values."""
+        for network in self.networks:
+            if all(network.attrs.get(k) == v for k, v in attr_dict.items()):
+                return network
+
     @staticmethod
     def get_logs(container):
         """Return the logs from a container."""
@@ -144,8 +164,10 @@ def __init__(self, **kwargs):
         self._ClientClass = PodmanClient
         if self.host == "localhost":
             self.uri = "unix:///run/user/1000/podman/podman.sock"
-        else:
+        elif kwargs.get("port") == SSH_PORT:
             self.uri = "http+ssh://{username}@{host}:{port}/run/podman/podman.sock".format(**kwargs)
+        else:
+            self.uri = "tcp://{host}:{port}".format(**kwargs)
 
     def _sanitize_create_args(self, kwargs):
         from podman.domain.containers_create import CreateMixin
@@ -176,7 +198,7 @@ def __init__(self, port=2375, **kwargs):
         if self.host == "localhost":
             self.uri = "unix://var/run/docker.sock"
         else:
-            self.uri = "ssh://{username}@{host}".format(**kwargs)
+            self.uri = "tcp://{username}@{host}".format(**kwargs)
 
     def _sanitize_create_args(self, kwargs):
         from docker.models.containers import RUN_CREATE_KWARGS, RUN_HOST_CONFIG_KWARGS

broker/providers/container.py

@@ -58,7 +58,8 @@ class Container(Provider):
         Validator(
             "CONTAINER.host_password",
         ),
-        Validator("CONTAINER.host_port", default=22),
+        Validator("CONTAINER.host_port", default=2375),
+        Validator("CONTAINER.network", default=None),
         Validator("CONTAINER.timeout", default=360),
         Validator("CONTAINER.auto_map_ports", is_type_of=bool, default=True),
     ]
@@ -213,7 +214,7 @@ def construct_host(self, provider_params, host_classes, **kwargs):
         # add the container's port mapping to the host instance only if there are any ports open
         if cont_attrs.get("ports"):
             host_inst.exposed_ports = {
-                f"{k.split('/')[0]}": v[0]["HostPort"] for k, v in cont_attrs["ports"].items()
+                f"{k.split('/')[0]}": v[0]["HostPort"] for k, v in cont_attrs["ports"].items() if v
             }
         return host_inst
 

broker_settings.yaml.example

@@ -35,6 +35,7 @@ Container:
             host_password: "<plain text password>"
             host_port: None
             runtime: docker
+            network: null
             default: True
         - remote:
             host: "<remote hostname>"

tests/data/container/fake_networks.json

@@ -0,0 +1,59 @@
+[
+    {
+        "name": "podman1",
+        "id": "78a8f74414",
+        "driver": "bridge",
+        "network_interface": "cni-podman1",
+        "created": "2024-04-29T04:39:08.09789015-04:00",
+        "subnets": [
+            {
+                "subnet": "fd00::1:8:0/112",
+                "gateway": "fd00::1:8:1"
+            }
+        ],
+        "ipv6_enabled": true,
+        "internal": false,
+        "dns_enabled": true,
+        "ipam_options": {
+            "driver": "host-local"
+        }
+    },
+    {
+        "name": "podman2",
+        "id": "c785da3b9b",
+        "driver": "bridge",
+        "network_interface": "cni-podman2",
+        "created": "2024-04-29T04:32:25.30689015-04:00",
+        "subnets": [
+            {
+                "subnet": "10.89.0.0/24",
+                "gateway": "10.89.0.1"
+            }
+        ],
+        "ipv6_enabled": false,
+        "internal": false,
+        "dns_enabled": true,
+        "ipam_options": {
+            "driver": "host-local"
+        }
+    },
+    {
+        "name": "podman",
+        "id": "c0b7a1bb95",
+        "driver": "bridge",
+        "network_interface": "cni-podman0",
+        "created": "2024-07-26T15:05:00.256703131-04:00",
+        "subnets": [
+            {
+                "subnet": "10.88.0.0/16",
+                "gateway": "10.88.0.1"
+            }
+        ],
+        "ipv6_enabled": false,
+        "internal": false,
+        "dns_enabled": false,
+        "ipam_options": {
+            "driver": "host-local"
+        }
+    }
+]

tests/providers/test_container.py

@@ -1,8 +1,10 @@
 import json
+from pathlib import Path
 import pytest
 from broker.broker import Broker
-from broker.providers.container import Container
 from broker.helpers import MockStub
+from broker.providers.container import Container
+from broker.settings import settings
 
 
 class ContainerApiStub(MockStub):
@@ -35,6 +37,16 @@ def __init__(self, **kwargs):
         else:
             super().__init__(in_dict=in_dict, **kwargs)
 
+    @property
+    def networks(self):
+        return [MockStub(obj) for obj in json.loads(Path("tests/data/container/fake_networks.json").read_text())]
+
+    def get_network_by_attrs(self, attr_dict):
+        """Return the first matching network that matches all attr_dict keys and values."""
+        for network in self.networks:
+            if all(network.attrs.get(k) == v for k, v in attr_dict.items()):
+                return network
+
     @staticmethod
     def pull_image(tag_name):
         with open("tests/data/container/fake_images.json") as image_file:
@@ -45,12 +57,17 @@ def pull_image(tag_name):
         raise Broker.ProviderError(f"Unable to find image: {tag_name}")
 
     def create_container(self, container_host, **kwargs):
+        if net_name := settings.container.network:
+            if not self.get_network_by_attrs({"name": net_name}):
+                raise Exception(f"Network '{settings.container.network}' not found on container host.")
+            kwargs["networks"] = {net_name: {"NetworkId": net_name}}
         with open("tests/data/container/fake_containers.json") as container_file:
             container_data = json.load(container_file)
         image_data = self.pull_image(container_host)
         for container in container_data:
             if container["Config"]["Image"] == image_data.RepoTags[0]:
                 container["id"] = container["Id"]  # hostname = cont_inst.id[:12]
+                container["kwargs"] = kwargs
                 return MockStub(container)
 
 
@@ -76,6 +93,12 @@ def test_host_creation(container_stub):
     assert host.hostname == "f37d3058317f"
 
 
+def test_ipv6_host_creation(container_stub):
+    settings.container.network = "podman2"
+    cont = container_stub.run_container(container_host="ch-d:ubi8")
+    assert cont.kwargs["networks"] == {'podman2': {'NetworkId': 'podman2'}}
+
+
 def test_image_lookup_failure(container_stub):
     with pytest.raises(Broker.ProviderError) as err:
         container_stub.run_container(container_host="this-does-not-exist")