add cache_images to lightning (#614)

* add cache_images to lightning

* fix cache_images in lightning

* add test for lightning cache_images

Author: Dave Berenbaum

src/dvclive/lightning.py

@@ -44,6 +44,7 @@ def __init__(
         report: Optional[str] = "auto",
         save_dvc_exp: bool = False,
         dvcyaml: bool = True,
+        cache_images: bool = False,
     ):
         super().__init__()
         self._prefix = prefix
@@ -52,6 +53,7 @@ def __init__(
             "report": report,
             "save_dvc_exp": save_dvc_exp,
             "dvcyaml": dvcyaml,
+            "cache_images": cache_images,
         }
         if dir is not None:
             self._live_init["dir"] = dir

tests/test_frameworks/test_lightning.py

@@ -144,7 +144,9 @@ def test_lightning_default_dir(tmp_dir):
 def test_lightning_kwargs(tmp_dir):
     model = LitXOR()
     # Handle kwargs passed to Live.
-    dvclive_logger = DVCLiveLogger(dir="dir", report="md", dvcyaml=False)
+    dvclive_logger = DVCLiveLogger(
+        dir="dir", report="md", dvcyaml=False, cache_images=True
+    )
     trainer = Trainer(
         logger=dvclive_logger,
         max_epochs=2,
@@ -156,6 +158,7 @@ def test_lightning_kwargs(tmp_dir):
     assert os.path.exists("dir")
     assert os.path.exists("dir/report.md")
     assert not os.path.exists("dir/dvc.yaml")
+    assert dvclive_logger.experiment._cache_images is True
 
 
 def test_lightning_steps(tmp_dir, mocker):