Pack: always pack files, explode directories to a list of files

When an asset is represented as directory in Blender (for example fluid
simulation caches), that directory is traced and each file is considered
an asset.

This makes it considerably easier for Shaman clients, as they need to
compute the SHA256 checksum of each file. The logic to transform a
directory path to a list of the contained files is now in BAT itself.

blender_asset_tracer/pack/__init__.py

@@ -554,9 +554,15 @@ class Packer:
             bfile.close()
 
     def _copy_asset_and_deps(self, asset_path: pathlib.Path, action: AssetAction):
+        asset_path_is_dir = asset_path.is_dir()
+
         # Copy the asset itself, but only if it's not a sequence (sequences are
         # handled below in the for-loop).
-        if "*" not in str(asset_path) and "<UDIM>" not in asset_path.name:
+        if (
+            "*" not in str(asset_path)
+            and "<UDIM>" not in asset_path.name
+            and not asset_path_is_dir
+        ):
             packed_path = action.new_path
             assert packed_path is not None
             read_path = action.read_from or asset_path
@@ -564,6 +570,11 @@ class Packer:
                 read_path, packed_path, may_move=action.read_from is not None
             )
 
+        if asset_path_is_dir:  # like 'some/directory':
+            asset_base_path = asset_path
+        else:  # like 'some/directory/prefix_*.bphys':
+            asset_base_path = asset_path.parent
+
         # Copy its sequence dependencies.
         for usage in action.usages:
             if not usage.is_sequence:
@@ -571,14 +582,24 @@ class Packer:
 
             first_pp = self._actions[usage.abspath].new_path
             assert first_pp is not None
+            log.info(f"first_pp = {first_pp}")
 
             # In case of globbing, we only support globbing by filename,
             # and not by directory.
             assert "*" not in str(first_pp) or "*" in first_pp.name
 
-            packed_base_dir = first_pp.parent
+            if asset_path_is_dir:
+                packed_base_dir = first_pp
+            else:
+                packed_base_dir = first_pp.parent
+
             for file_path in usage.files():
-                packed_path = packed_base_dir / file_path.name
+                # Compute the relative path, to support cases where asset_path
+                # is `some/directory` and the to-be-copied file is in
+                # `some/directory/subdir/filename.txt`.
+                relpath = file_path.relative_to(asset_base_path)
+                packed_path = packed_base_dir / relpath
+
                 # Assumption: assets in a sequence are never blend files.
                 self._send_to_target(file_path, packed_path)
 

blender_asset_tracer/pack/transfer.py

@@ -90,6 +90,8 @@ class FileTransferer(threading.Thread, metaclass=abc.ABCMeta):
 
     def queue_copy(self, src: pathlib.Path, dst: pathlib.PurePath):
         """Queue a copy action from 'src' to 'dst'."""
+        if src.is_dir():
+            raise TypeError(f"only files can be copied, not directories: {src}")
         assert (
             not self.done.is_set()
         ), "Queueing not allowed after done_and_join() was called"
@@ -103,6 +105,8 @@ class FileTransferer(threading.Thread, metaclass=abc.ABCMeta):
 
     def queue_move(self, src: pathlib.Path, dst: pathlib.PurePath):
         """Queue a move action from 'src' to 'dst'."""
+        if src.is_dir():
+            raise TypeError(f"only files can be moved, not directories: {src}")
         assert (
             not self.done.is_set()
         ), "Queueing not allowed after done_and_join() was called"

blender_asset_tracer/trace/file_sequence.py

@@ -56,7 +56,10 @@ def expand_sequence(path: pathlib.Path) -> typing.Iterator[pathlib.Path]:
         raise DoesNotExist(path)
 
     if path.is_dir():
-        yield path
+        # Explode directory paths into separate files.
+        for subpath in path.rglob("*"):
+            if subpath.is_file():
+                yield subpath
         return
 
     log.debug("expanding file sequence %s", path)