fix: Fix error message in VllmGenerationWorker. (#633)

Signed-off-by: Felipe Vieira Frujeri <ffrujeri@nvidia.com>

Author: ffrujeri

nemo_rl/models/generation/vllm.py

@@ -286,7 +286,8 @@ def _patch_vllm_init_workers_ray():
             raise ImportError(
                 "vLLM is not installed. Please check that the py_executable in the runtime_env of VllmGenerationWorker "
                 "covers the vllm dependency. You may have to update nemo_rl/distributed/ray_actor_environment_registry.py. "
-                "If you are working interactively, you can install by running  `uv sync --extra vllm` anywhere in the repo."
+                "This error can also happen if the venv creation was aborted or errored out in the middle. In that case, "
+                "please run at least once with the environment variable NRL_FORCE_REBUILD_VENVS=true set to force the rebuild of the environment."
             )
         vllm_kwargs: dict[str, Any] = copy.deepcopy(self.cfg.get("vllm_kwargs", {}))
 

nemo_rl/models/generation/vllm_backend.py

@@ -23,7 +23,8 @@
     raise ImportError(
         "vLLM is not installed. Please check that the py_executable in the runtime_env of VllmGenerationWorker "
         "covers the vllm dependency. You may have to update nemo_rl/distributed/ray_actor_environment_registry.py. "
-        "If you are working interactively, you can install by running  `uv sync --extra vllm` anywhere in the repo."
+        "This error can also happen if the venv creation was aborted or errored out in the middle. In that case, "
+        "please run at least once with the environment variable NRL_FORCE_REBUILD_VENVS=true set to force the rebuild of the environment."
     )