Log checkpoints as mlflow artifacts (#1976)

* Ensure hf_mlflow_log_artifact config var is set in env

* Add transformer MLflowCallback to callbacks list when mlflow enabled

* Test hf_mlflow_log_artifacts is set correctly

* Test mlflow not being used by default

src/axolotl/core/trainer_builder.py

@@ -1119,12 +1119,17 @@ class TrainerBuilderBase(abc.ABC):
                 SaveAxolotlConfigtoWandBCallback(self.cfg.axolotl_config_path)
             )
         if self.cfg.use_mlflow and is_mlflow_available():
+            from transformers.integrations.integration_utils import MLflowCallback
+
             from axolotl.utils.callbacks.mlflow_ import (
                 SaveAxolotlConfigtoMlflowCallback,
             )
 
-            callbacks.append(
+            callbacks.extend(
-                SaveAxolotlConfigtoMlflowCallback(self.cfg.axolotl_config_path)
+                [
+                    SaveAxolotlConfigtoMlflowCallback(self.cfg.axolotl_config_path),
+                    MLflowCallback,
+                ]
             )
         if self.cfg.use_comet and is_comet_available():
             from axolotl.utils.callbacks.comet_ import SaveAxolotlConfigtoCometCallback

src/axolotl/utils/mlflow_.py

@@ -16,3 +16,7 @@ def setup_mlflow_env_vars(cfg: DictDefault):
     # Enable mlflow if experiment name is present
     if cfg.mlflow_experiment_name and len(cfg.mlflow_experiment_name) > 0:
         cfg.use_mlflow = True
+
+    # Enable logging hf artifacts in mlflow if value is truthy
+    if cfg.hf_mlflow_log_artifacts is True:
+        os.environ["HF_MLFLOW_LOG_ARTIFACTS"] = "true"

tests/test_validation.py

@@ -13,6 +13,7 @@ from axolotl.utils import is_comet_available
 from axolotl.utils.config import validate_config
 from axolotl.utils.config.models.input.v0_4_1 import AxolotlConfigWCapabilities
 from axolotl.utils.dict import DictDefault
+from axolotl.utils.mlflow_ import setup_mlflow_env_vars
 from axolotl.utils.models import check_model_config
 from axolotl.utils.wandb_ import setup_wandb_env_vars
 
@@ -1432,3 +1433,58 @@ class TestValidationComet(BaseValidation):
 
         for key in comet_env.keys():
             os.environ.pop(key, None)
+
+
+class TestValidationMLflow(BaseValidation):
+    """
+    Validation test for MLflow
+    """
+
+    def test_hf_mlflow_artifacts_config_sets_env(self, minimal_cfg):
+        cfg = (
+            DictDefault(
+                {
+                    "hf_mlflow_log_artifacts": True,
+                }
+            )
+            | minimal_cfg
+        )
+
+        new_cfg = validate_config(cfg)
+
+        assert new_cfg.hf_mlflow_log_artifacts is True
+
+        # Check it's not already present in env
+        assert "HF_MLFLOW_LOG_ARTIFACTS" not in os.environ
+
+        setup_mlflow_env_vars(new_cfg)
+
+        assert os.environ.get("HF_MLFLOW_LOG_ARTIFACTS") == "true"
+
+        os.environ.pop("HF_MLFLOW_LOG_ARTIFACTS", None)
+
+    def test_mlflow_not_used_by_default(self, minimal_cfg):
+        cfg = DictDefault({}) | minimal_cfg
+
+        new_cfg = validate_config(cfg)
+
+        setup_mlflow_env_vars(new_cfg)
+
+        assert cfg.use_mlflow is not True
+
+        cfg = (
+            DictDefault(
+                {
+                    "mlflow_experiment_name": "foo",
+                }
+            )
+            | minimal_cfg
+        )
+
+        new_cfg = validate_config(cfg)
+
+        setup_mlflow_env_vars(new_cfg)
+
+        assert new_cfg.use_mlflow is True
+
+        os.environ.pop("MLFLOW_EXPERIMENT_NAME", None)