feat(core)!: add support for tc.host and de-prioritise docker:dind

core/testcontainers/core/container.py

@@ -90,18 +90,18 @@ def get_container_host_ip(self) -> str:
         if not host:
             return "localhost"
 
-        # check testcontainers itself runs inside docker container
-        if inside_container() and not os.getenv("DOCKER_HOST"):
-            # If newly spawned container's gateway IP address from the docker
-            # "bridge" network is equal to detected host address, we should use
-            # container IP address, otherwise fall back to detected host
-            # address. Even it's inside container, we need to double check,
-            # because docker host might be set to docker:dind, usually in CI/CD environment
-            gateway_ip = self.get_docker_client().gateway_ip(self._container.id)
-
-            if gateway_ip == host:
-                return self.get_docker_client().bridge_ip(self._container.id)
-            return gateway_ip
+        # # check testcontainers itself runs inside docker container
+        # if inside_container() and not os.getenv("DOCKER_HOST") and not host.startswith("http://"):
+        #     # If newly spawned container's gateway IP address from the docker
+        #     # "bridge" network is equal to detected host address, we should use
+        #     # container IP address, otherwise fall back to detected host
+        #     # address. Even it's inside container, we need to double check,
+        #     # because docker host might be set to docker:dind, usually in CI/CD environment
+        #     gateway_ip = self.get_docker_client().gateway_ip(self._container.id)
+
+        #     if gateway_ip == host:
+        #         return self.get_docker_client().bridge_ip(self._container.id)
+        #     return gateway_ip
         return host
 
     @wait_container_is_ready()

core/testcontainers/core/docker_client.py

@@ -40,7 +40,22 @@ class DockerClient:
     Thin wrapper around :class:`docker.DockerClient` for a more functional interface.
     """
     def __init__(self, **kwargs) -> None:
-        self.client = docker.from_env(**kwargs)
+        docker_host = DockerClient.read_docker_host_from_properties()
+
+        if docker_host:
+            print(f"using host {docker_host}")
+            self.client = docker.DockerClient(base_url=docker_host)
+        else:
+            self.client = docker.from_env(**kwargs)
+
+    def read_docker_host_from_properties():
+        try:
+            with open(os.path.expanduser('~/.testcontainers.properties')) as f:
+                for line in f:
+                    if line.startswith('tc.host'):
+                        return line.split('=')[1].strip()
+        except FileNotFoundError:
+            return None
 
     @ft.wraps(ContainerCollection.run)
     def run(self, image: str, command: Union[str, List[str]] = None,