feat: separate builder

Author: KeplerC

fog_x/dataset.py

@@ -381,12 +381,53 @@ def load_rtx_episodes(
         import tensorflow_datasets as tfds
 
         from fog_x.rlds.utils import dataset2path
-
         b = tfds.builder_from_directory(builder_dir=dataset2path(name))
+        self._build_rtx_episodes_from_tfds_builder(
+            b,
+            split=split,
+            additional_metadata=additional_metadata,
+        )
+
+    def load_rtx_episodes_local(
+        self,
+        path: str,
+        split: str = "all",
+        additional_metadata: Optional[Dict[str, Any]] = dict(),
+    ):
+        """
+        Load robot data from Tensorflow Datasets.
 
-        ds = b.as_dataset(split=split)
+        Args:
+            path (str): Path to the RT-X episodes
+            split (optional str): the portion of data to load, see [Tensorflow Split API](https://www.tensorflow.org/datasets/splits)
+            additional_metadata (optional Dict[str, Any]): additional metadata to be associated with the loaded episodes
 
-        data_type = b.info.features["steps"]
+        Example:
+            ```
+            >>> dataset.load_rtx_episodes_local(path="~/Downloads/berkeley_autolab_ur5")
+            >>> dataset.load_rtx_episodes_local(path="~/Downloads/berkeley_autolab_ur5", split="train[:10]", additional_metadata={"data_collector": "Alice", "custom_tag": "sample"})
+            ```
+        """
+
+        # this is only required if rtx format is used
+        import tensorflow_datasets as tfds
+
+        b = tfds.builder(path)
+        self._build_rtx_episodes_from_tfds_builder(
+            b,
+            split=split,
+            additional_metadata=additional_metadata,
+        )
+
+    def _build_rtx_episodes_from_tfds_builder(
+        builder,
+    ):
+        """
+        construct the dataset from the tfds builder
+        """
+        ds = builder.as_dataset(split=split)
+
+        data_type = builder.info.features["steps"]
 
         for tf_episode in ds:
             logger.info(tf_episode)