#3359 - Reuse Docker-on-request for AWSLambda and Batch

moto/utilities/docker.py

@@ -0,0 +1,33 @@
+import docker
+import functools
+import requests.adapters
+
+
+_orig_adapter_send = requests.adapters.HTTPAdapter.send
+
+
+class DockerModel:
+    def __init__(self):
+        self.__docker_client = None
+
+    @property
+    def docker_client(self):
+        if self.__docker_client is None:
+            # We should only initiate the Docker Client at runtime.
+            # The docker.from_env() call will fall if Docker is not running
+            self.__docker_client = docker.from_env()
+
+            # Unfortunately mocking replaces this method w/o fallback enabled, so we
+            # need to replace it if we detect it's been mocked
+            if requests.adapters.HTTPAdapter.send != _orig_adapter_send:
+                _orig_get_adapter = self.docker_client.api.get_adapter
+
+                def replace_adapter_send(*args, **kwargs):
+                    adapter = _orig_get_adapter(*args, **kwargs)
+
+                    if isinstance(adapter, requests.adapters.HTTPAdapter):
+                        adapter.send = functools.partial(_orig_adapter_send, adapter)
+                    return adapter
+
+                self.docker_client.api.get_adapter = replace_adapter_send
+        return self.__docker_client