trying yet again to make work for both streaming settings

merfish.py

@@ -1,11 +1,13 @@
 import datasets
 import os
-import glob
 import pandas as pd
+import pyarrow.parquet as pq
+
 
 class MERFISHConfig(datasets.BuilderConfig):
-    def __init__(self, name, **kwargs):
-        super().__init__(name=name, **kwargs)
+    def __init__(self, **kwargs):
+        self.gene_subset = kwargs.pop("gene_subset", None)
+        super().__init__(**kwargs)
 
 class MERFISH(datasets.GeneratorBasedBuilder):
     BUILDER_CONFIGS = [
@@ -25,36 +27,55 @@ class MERFISH(datasets.GeneratorBasedBuilder):
         )
 
     def _split_generators(self, dl_manager):
-        data_files = {
-            "expression": os.path.join(self.config.name, "expression", "*.parquet"),
-            "gene_metadata": os.path.join(self.config.name, "gene_metadata.parquet"),
-            "cell_metadata": os.path.join(self.config.name, "cell_metadata.parquet"),
-        }
-        downloaded = dl_manager.download(data_files)
+        base_path = os.path.join(self.config.name, "expression")
+
+        if dl_manager.is_streaming:
+            expression_files = list(dl_manager.iter_files(base_path))
+        else:
+            expression_dir = dl_manager.download_and_extract(base_path)
+            expression_files = sorted([
+                os.path.join(expression_dir, f)
+                for f in os.listdir(expression_dir)
+                if f.endswith(".parquet")
+            ])
+
+        gene_metadata = dl_manager.download(os.path.join(self.config.name, "gene_metadata.parquet"))
+        cell_metadata = dl_manager.download(os.path.join(self.config.name, "cell_metadata.parquet"))
+
         return [
             datasets.SplitGenerator(
                 name=datasets.Split.TRAIN,
                 gen_kwargs={
-                    "expression_files": sorted(glob.glob(downloaded["expression"])),
-                    "gene_metadata_path": downloaded["gene_metadata"],
-                    "cell_metadata_path": downloaded["cell_metadata"],
+                    "expression_files": expression_files,
+                    "gene_metadata_path": gene_metadata,
+                    "cell_metadata_path": cell_metadata,
+                    "fs": dl_manager.fs if dl_manager.is_streaming else None,
                 },
             ),
         ]
 
-    def _generate_examples(self, expression_files, gene_metadata_path, cell_metadata_path):
-        gene_df = pd.read_parquet(gene_metadata_path)
+    def _generate_examples(self, expression_files, gene_metadata_path, cell_metadata_path, fs):
+        if fs is not None:
+            gene_df = pd.read_parquet(fs.open(gene_metadata_path))
+            cell_df = pd.read_parquet(fs.open(cell_metadata_path))
+        else:
+            gene_df = pd.read_parquet(gene_metadata_path)
+            cell_df = pd.read_parquet(cell_metadata_path)
+
         gene_names = gene_df["gene_id"].tolist() if "gene_id" in gene_df.columns else gene_df.index.tolist()
-        cell_df = pd.read_parquet(cell_metadata_path)
 
         idx = 0
         for filepath in expression_files:
-            df = pd.read_parquet(filepath)
+            if fs is not None:
+                f = fs.open(filepath, "rb")
+                df = pd.read_parquet(f)
+            else:
+                df = pd.read_parquet(filepath)
+
             for cell_id, row in df.iterrows():
                 yield idx, {
-                    "cell_id": cell_id,
+                    "cell_id": str(cell_id),
                     "expression": row.to_numpy(dtype="float32").tolist(),
                     "gene_names": gene_names,
                 }
                 idx += 1
-