add POST /grader endpoint for validator

server/app.py

@@ -1,4 +1,4 @@
-"""FastAPI application for ConfigDebugEnv v2.
+"""FastAPI application for ConfigDebugEnv.
 
 Uses OpenEnv's create_fastapi_app() for standard framework compatibility
 (WebSocket sessions, standard endpoints, grader discovery).
@@ -86,11 +86,7 @@ def health():
 
 @app.get("/metadata")
 def metadata():
-    """Metadata endpoint with grader paths for validator discovery.
-
-    The validator uses these grader paths to import and test each grader.
-    Each grader path points to grader_api which returns a FLOAT in (0.01, 0.99).
-    """
+    """Metadata endpoint with grader paths for validator discovery."""
     print("[VALIDATOR] GET /metadata called")
     return {
         "name": "ConfigDebugEnvironment",
@@ -109,10 +105,7 @@ def metadata():
 
 @app.post("/reset")
 async def reset_env(request: Request):
-    """Override /reset endpoint to return correct OpenEnv contract schema.
-
-    Must include: observation, done, reward (as float, NOT null), metadata, info
-    """
+    """Override /reset endpoint to return correct OpenEnv contract schema."""
     print("[VALIDATOR] POST /reset called - CUSTOM OVERRIDE")
     try:
         env = ConfigDebugEnvironment()
@@ -131,6 +124,45 @@ async def reset_env(request: Request):
         raise
 
 
+@app.post("/grader")
+async def grader_endpoint(request: Request):
+    """Score a submitted config for a specific task without a full episode.
+    The validator calls this to verify each task has a working grader
+    with scores strictly between 0 and 1."""
+    print("[VALIDATOR] POST /grader called")
+    try:
+        body = await request.json()
+        task_id = body.get("task_id", TASK_ORDER[0])
+        submitted_config = body.get("submitted_config",
+            body.get("action", {}).get("fixed_config", "{}"))
+
+        from server.graders.grader_api import (
+            grade_task1, grade_task2, grade_task3,
+            grade_task4, grade_task5, grade_task6, grade_task7,
+        )
+
+        grader_map = {
+            "task1_json": grade_task1,
+            "task2_yaml": grade_task2,
+            "task3_dockerfile": grade_task3,
+            "task4_compose": grade_task4,
+            "task5_k8s": grade_task5,
+            "task6_github_actions": grade_task6,
+            "task7_nginx": grade_task7,
+        }
+
+        grader_fn = grader_map.get(task_id)
+        if grader_fn is None:
+            return {"error": f"Unknown task_id: {task_id}", "score": 0.01}
+
+        score = grader_fn(submitted_config)
+        print(f"[GRADER] task={task_id} score={score}")
+        return {"task_id": task_id, "score": score, "has_grader": True}
+    except Exception as e:
+        print(f"[GRADER] Error: {e}")
+        return {"error": str(e), "score": 0.01}
+
+
 @app.get("/tasks")
 def tasks():
     return {
@@ -274,4 +306,4 @@ def main(host: str = "0.0.0.0", port: int = 7860):
 
 
 if __name__ == "__main__":
-    main()
+    main()