feat: add fsspec as required dependency (#1021)

* fsspec requirements

* simplify fsspec import

* use loop property

* correctly create schemes list

pyproject.toml

@@ -36,6 +36,7 @@ dependencies = [
   "awkward>=2.4.6",
   "importlib-metadata;python_version<\"3.8\"",
   "numpy",
+  "fsspec",
   "packaging",
   "typing_extensions>=4.1.0; python_version < \"3.11\""
 ]
@@ -61,7 +62,6 @@ test = [
   "lz4",
   "minio",
   "aiohttp; python_version<\"3.12\"",  # asyncio not available
-  "fsspec",
   "fsspec-xrootd",
   "s3fs; python_version<\"3.12\"",  # asyncio not available
   "paramiko",

src/uproot/_util.py

@@ -19,6 +19,7 @@
 from collections.abc import Iterable
 from urllib.parse import unquote, urlparse
 
+import fsspec
 import numpy
 import packaging.version
 
@@ -275,15 +276,7 @@ def regularize_path(path):
 _windows_absolute_path_pattern_slash = re.compile(r"^[\\/][A-Za-z]:[\\/]")
 
 _remote_schemes = ["root", "s3", "http", "https"]
-_schemes = ["file", *_remote_schemes]
-
-try:
-    # TODO: remove this try/except when fsspec becomes a required dependency
-    import fsspec
-
-    _schemes = list({*_schemes, *fsspec.available_protocols()})
-except ImportError:
-    pass
+_schemes = list({*_remote_schemes, *fsspec.available_protocols()})
 
 _uri_scheme = re.compile("^(" + "|".join([re.escape(x) for x in _schemes]) + ")://")
 _uri_scheme_chain = re.compile(

src/uproot/source/fsspec.py

@@ -6,6 +6,9 @@
 import concurrent.futures
 import queue
 
+import fsspec
+import fsspec.asyn
+
 import uproot
 import uproot.source.chunk
 import uproot.source.futures
@@ -24,8 +27,6 @@ class FSSpecSource(uproot.source.chunk.Source):
     """
 
     def __init__(self, file_path: str, **options):
-        import fsspec.core
-
         default_options = uproot.reading.open.defaults
 
         exclude_keys = set(default_options.keys())
@@ -189,8 +190,6 @@ def closed(self) -> bool:
 class FSSpecLoopExecutor(uproot.source.futures.Executor):
     @property
     def loop(self) -> asyncio.AbstractEventLoop:
-        import fsspec.asyn
-
         return fsspec.asyn.get_loop()
 
     def submit(self, coroutine) -> concurrent.futures.Future: