Generate sync methods from async ones

.pre-commit-config.yaml

@@ -9,11 +9,14 @@
 
 # NB: In this config we exclude the example and tests notebooks
 # from the code hooks (black, flake8, etc) as we want to keep
-# the text representation of the test notebooks unchanged
+# the text representation of the test notebooks unchanged, plus
+# the (sync) contentsmanager.py which is generated from the async one.
 exclude: >
     (?x)^(
       demo/.*|
       tests/data/notebooks/.*|
+      src/jupytext/sync_pairs.py|
+      src/jupytext/sync_contentsmanager.py|
     )$
 repos:
 

CHANGELOG.md

@@ -5,6 +5,7 @@ Jupytext ChangeLog
 ----------
 
 **Changed**
+- Jupytext's default contents manager is now derived from the asynchronous AsyncLargeFileManager. Thanks to [Darshan Poudel](https://github.com/Darshan808) for making this finally happen ([#1328](https://github.com/mwouts/jupytext/pull/1328))!
 - We have updated the JupyterLab extension dependencies ([#1300](https://github.com/mwouts/jupytext/pull/1300)). Thanks to [Mahendra Paipuri](https://github.com/mahendrapaipuri) for this PR!
 
 

jupyterlab/jupyterlab_jupytext/__init__.py

@@ -2,12 +2,8 @@
 
 import asyncio
 
-from jupytext.reraise import reraise
-
-try:
-    from jupytext.contentsmanager import build_jupytext_contents_manager_class
-except ImportError as err:
-    build_jupytext_contents_manager = reraise(err)
+from jupytext.async_contentsmanager import build_async_jupytext_contents_manager_class
+from jupytext.sync_contentsmanager import build_sync_jupytext_contents_manager_class
 
 
 def load_jupyter_server_extension(app):  # pragma: no cover
@@ -22,26 +18,24 @@ def load_jupyter_server_extension(app):  # pragma: no cover
     # The server extension call is too late!
     # The contents manager was set at NotebookApp.init_configurables
 
-    # If possible, we derive a Jupytext CM from the current CM
     base_class = app.contents_manager_class
-    if asyncio.iscoroutinefunction(base_class.get):
-        app.log.warning(
-            f"[Jupytext Server Extension] Async contents managers like {base_class.__name__} "
-            "are not supported at the moment "
-            "(https://github.com/mwouts/jupytext/issues/1020). "
-            "We will derive a contents manager from LargeFileManager instead."
-        )
-        from jupyter_server.services.contents.largefilemanager import (  # noqa
-            LargeFileManager,
-        )
-
-        base_class = LargeFileManager
 
+    asynchronous = asyncio.iscoroutinefunction(base_class.get)
     app.log.info(
-        "[Jupytext Server Extension] Deriving a JupytextContentsManager "
-        "from {}".format(base_class.__name__)
+        "[Jupytext Server Extension] Deriving "
+        + ("an Async" if asynchronous else "a ")
+        + "TextFileContentsManager from "
+        + base_class.__name__
     )
-    app.contents_manager_class = build_jupytext_contents_manager_class(base_class)
+
+    if asyncio.iscoroutinefunction(base_class.get):
+        app.contents_manager_class = build_async_jupytext_contents_manager_class(
+            base_class
+        )
+    else:
+        app.contents_manager_class = build_sync_jupytext_contents_manager_class(
+            base_class
+        )
 
     try:
         # And rerun selected init steps from https://github.com/jupyter/notebook/blob/

pyproject.toml

@@ -33,6 +33,7 @@ classifiers = [
 ]
 dependencies = [
     "nbformat",
+    "jupyter_server",
     "mdit-py-plugins",
     "markdown-it-py>=1.0",
     "packaging",
@@ -50,6 +51,7 @@ Documentation = "https://jupytext.readthedocs.io"
 # Test related dependencies
 test = [
   "pytest",
+  "pytest-asyncio",
   "pytest-xdist",
   "pytest-randomly"
 ]
@@ -205,6 +207,7 @@ markers = [
     "requires_ir_kernel",
     "skip_on_windows",
     "pre_commit",
+    "asyncio"
 ]
 filterwarnings = [
     # Uncomment this "error" to turn all unfiltered warnings into errors

src/jupytext/__init__.py

@@ -1,20 +1,17 @@
 """Read and write Jupyter notebooks as text files"""
 
+from .async_contentsmanager import (
+    AsyncTextFileContentsManager,
+    build_async_jupytext_contents_manager_class,
+)
 from .formats import NOTEBOOK_EXTENSIONS, get_format_implementation, guess_format
 from .jupytext import read, reads, write, writes
-from .reraise import reraise
+from .sync_contentsmanager import (
+    TextFileContentsManager,
+    build_sync_jupytext_contents_manager_class,
+)
 from .version import __version__
 
-try:
-    from .contentsmanager import build_jupytext_contents_manager_class
-except ImportError as err:
-    build_jupytext_contents_manager_class = reraise(err)
-
-try:
-    from .contentsmanager import TextFileContentsManager
-except ImportError as err:
-    TextFileContentsManager = reraise(err)
-
 __all__ = [
     "read",
     "write",
@@ -24,6 +21,8 @@
     "guess_format",
     "get_format_implementation",
     "TextFileContentsManager",
-    "build_jupytext_contents_manager_class",
+    "AsyncTextFileContentsManager",
+    "build_sync_jupytext_contents_manager_class",
+    "build_async_jupytext_contents_manager_class",
     "__version__",
 ]