pass backend cls, instantiate backend in task

Author: ollmer

src/agentlab/backends/browser/env.py

@@ -133,18 +133,23 @@ class BrowserEnvArgs(AbstractEnvArgs):
     task: AbstractWebTask
     task_seed: int
     task_name: str
-    backend: BrowserBackend
+    backend_cls: type[BrowserBackend]
 
     def __init__(
-        self, task_name: str, task: AbstractWebTask, backend: BrowserBackend, task_seed: int = 0
+        self,
+        task_name: str,
+        task: AbstractWebTask,
+        backend_cls: type[BrowserBackend],
+        task_seed: int = 0,
     ):
         self.task_name = task_name
         self.task = task
         self.task_seed = task_seed
-        self.backend = backend
+        self.backend_cls = backend_cls
 
     def make_env(self, exp_dir: Path) -> BrowserEnv:
+        backend = self.backend_cls()
         env = BrowserEnv(
-            task_name=self.task_name, task=self.task, backend=self.backend, seed=self.task_seed
+            task_name=self.task_name, task=self.task, backend=backend, seed=self.task_seed
         )
         return env

src/agentlab/benchmarks/miniwob/benchmark.py

@@ -1,7 +1,7 @@
 import logging
 from typing import Any
 
-from pydantic import ConfigDict, Field
+from pydantic import ConfigDict
 
 from agentlab.actions import ToolsActionSet
 from agentlab.backends.browser.base import BrowserBackend
@@ -15,20 +15,20 @@
 class MiniWobBenchmark(AbstractBenchmark):
     model_config = ConfigDict(arbitrary_types_allowed=True)
 
-    backend: BrowserBackend
+    backend_cls: type[BrowserBackend]
     name: str = "miniwob"
     env_args_list: list[BrowserEnvArgs] = None  # type: ignore
     dataset: list[MiniWobTask] = None  # type: ignore
     is_multi_tab: bool = False
-    high_level_action_set_args: ToolsActionSet = None
+    high_level_action_set_args: ToolsActionSet = None  # type: ignore
 
     def model_post_init(self, __context: Any) -> None:
-        self.name = f"miniwob_{self.backend.__class__.__name__.lower()}"
+        self.name = f"miniwob_{self.backend_cls.__name__.lower()}"
         self.env_args_list = []
         if self.dataset is None:
             self.dataset = get_miniwob_tasks()
         for task in self.dataset:
             name = f"miniwob.{task.task_id}"
-            env_args = BrowserEnvArgs(task_name=name, task=task, backend=self.backend)
+            env_args = BrowserEnvArgs(task_name=name, task=task, backend_cls=self.backend_cls)
             self.env_args_list.append(env_args)
         logger.info(f"Loaded {len(self.env_args_list)} miniwob tasks")