Enh: make docker_internal_host configurable with default value (#266)

Closes #253

* fix: make docker_internal_host configurable with default value #253 issue

* Apply suggestion from @klieret

---------

Co-authored-by: Kilian Lieret <[email protected]>

Author: SkipperNZ

src/swerex/deployment/config.py

@@ -45,6 +45,12 @@ class DockerDeploymentConfig(BaseModel):
     """The container runtime to use (docker or podman)."""
     exec_shell: list[str] = ["/bin/sh", "-c"]
     """The shell executable and arguments to use for running commands."""
+    docker_internal_host: str = "http://127.0.0.1"
+    """The host to use for connecting to the runtime.
+    In most cases you can leave this as-is, however for docker-in-docker
+    setups you might have to set it to http://host.docker.internal/ 
+    (see https://github.com/SWE-agent/SWE-ReX/issues/253 for more information).
+    """
 
     type: Literal["docker"] = "docker"
     """Discriminator for (de)serialization/CLI. Do not change."""

src/swerex/deployment/docker.py

@@ -271,7 +271,12 @@ async def start(self):
         self._hooks.on_custom_step("Starting runtime")
         self.logger.info(f"Starting runtime at {self._config.port}")
         self._runtime = RemoteRuntime.from_config(
-            RemoteRuntimeConfig(port=self._config.port, timeout=self._runtime_timeout, auth_token=token)
+            RemoteRuntimeConfig(
+                host=self._config.docker_internal_host,
+                port=self._config.port,
+                timeout=self._runtime_timeout,
+                auth_token=token,
+            )
         )
         t0 = time.time()
         await self._wait_until_alive(timeout=self._config.startup_timeout)