test: dump debug information if http request to firecracker fails

Sometimes, we intermittently see `ConnectionRefused` errors when doing
http requests to the firecracker API in integration tests. Have the test
framework dump relevant logs in these cases.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

tests/framework/http_api.py

@@ -58,15 +58,25 @@ def __init__(self, api, resource, id_field=None):
     def get(self):
         """Make a GET request"""
         url = self._api.endpoint + self.resource
-        res = self._api.session.get(url)
+        try:
+            res = self._api.session.get(url)
+        except Exception as e:
+            if self._api.error_callback:
+                self._api.error_callback("GET", self.resource, str(e))
+            raise
         assert res.status_code == HTTPStatus.OK, res.json()
         return res
 
     def request(self, method, path, **kwargs):
         """Make an HTTP request"""
         kwargs = {key: val for key, val in kwargs.items() if val is not None}
         url = self._api.endpoint + path
-        res = self._api.session.request(method, url, json=kwargs)
+        try:
+            res = self._api.session.request(method, url, json=kwargs)
+        except Exception as e:
+            if self._api.error_callback:
+                self._api.error_callback(method, path, str(e))
+            raise
         if res.status_code != HTTPStatus.NO_CONTENT:
             json = res.json()
             msg = res.content
@@ -95,7 +105,8 @@ def patch(self, **kwargs):
 class Api:
     """A simple HTTP client for the Firecracker API"""
 
-    def __init__(self, api_usocket_full_name):
+    def __init__(self, api_usocket_full_name, *, on_error=None):
+        self.error_callback = on_error
         self.socket = api_usocket_full_name
         url_encoded_path = urllib.parse.quote_plus(api_usocket_full_name)
         self.endpoint = DEFAULT_SCHEME + url_encoded_path

tests/framework/microvm.py

@@ -615,7 +615,12 @@ def spawn(
         # pylint: disable=subprocess-run-check
         # pylint: disable=too-many-branches
         self.jailer.setup()
-        self.api = Api(self.jailer.api_socket_path())
+        self.api = Api(
+            self.jailer.api_socket_path(),
+            on_error=lambda verb, uri, err_msg: self._dump_debug_information(
+                f"Error during {verb} {uri}: {err_msg}"
+            ),
+        )
 
         if log_file is not None:
             self.log_file = Path(self.path) / log_file