Fix async contents handling and add test (#6616)

* Fix async contents handling and add test

* cleanup

* fix arg

* add another ignore

.github/workflows/build.yml

@@ -58,6 +58,29 @@ jobs:
         jupyter server extension list 2>&1 | grep -ie "notebook.*enabled" -
         python -m jupyterlab.browser_check
 
+  test_prerelease:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v3
+
+    - name: Base Setup
+      uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+      with:
+        python_version: "3.10"
+
+    - name: Install the Python dependencies
+      run: |
+        pip install --no-deps .
+        pip install --pre --upgrade ".[dev,test]"
+        python -m pip install ".[dev,test]"
+        jlpm run build:test
+
+    - name: Python Unit tests
+      run: |
+        pytest -vv || pytest -vv --lf
+
   install:
     needs: [build]
     runs-on: ${{ matrix.os }}
@@ -116,7 +139,7 @@ jobs:
       - uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
       - uses: jupyterlab/maintainer-tools/.github/actions/check-links@v1
         with:
-          ignore_links: "https://playwright.dev/docs/test-cli/"
+          ignore_links: "https://playwright.dev/docs/test-cli/ https://blog.jupyter.org/the-big-split-9d7b88a031a7 https://blog.jupyter.org/jupyter-ascending-1bf5b362d97e"
 
   pre_commit:
     runs-on: ubuntu-latest

notebook/app.py

@@ -1,6 +1,7 @@
 import os
 from os.path import join as pjoin
 
+from jupyter_client.utils import ensure_async
 from jupyter_core.application import base_aliases
 from jupyter_server.base.handlers import JupyterHandler
 from jupyter_server.extension.handler import (
@@ -16,7 +17,6 @@ from jupyterlab_server.config import LabConfig, get_page_config, recursive_updat
 from jupyterlab_server.handlers import _camelCase, is_url
 from notebook_shim.shim import NotebookConfigShimMixin
 from tornado import web
-from tornado.gen import maybe_future
 from traitlets import Bool, default
 
 from ._version import __version__
@@ -129,8 +129,8 @@ class TreeHandler(NotebookBaseHandler):
         path = path.strip("/")
         cm = self.contents_manager
 
-        if await maybe_future(cm.dir_exists(path=path)):
-            if await maybe_future(cm.is_hidden(path)) and not cm.allow_hidden:
+        if await ensure_async(cm.dir_exists(path=path)):
+            if await ensure_async(cm.is_hidden(path)) and not cm.allow_hidden:
                 self.log.info("Refusing to serve hidden directory, via 404 Error")
                 raise web.HTTPError(404)
 
@@ -140,9 +140,9 @@ class TreeHandler(NotebookBaseHandler):
 
             tpl = self.render_template("tree.html", page_config=page_config)
             return self.write(tpl)
-        elif await maybe_future(cm.file_exists(path)):
+        elif await ensure_async(cm.file_exists(path)):
             # it's not a directory, we have redirecting to do
-            model = await maybe_future(cm.get(path, content=False))
+            model = await ensure_async(cm.get(path, content=False))
             if model["type"] == "notebook":
                 url = ujoin(self.base_url, "notebooks", url_escape(path))
             else:

tests/conftest.py

@@ -1,3 +1,4 @@
+import glob
 import json
 import os
 import os.path as osp
@@ -49,7 +50,11 @@ def make_notebook_app(
             extra_labextensions_path=[str(labextensions_dir)],
         )
 
-    # Create the index files.
+    # Copy the template files.
+    for html_path in glob.glob(f"{path('notebook', 'templates')}/*.html"):
+        shutil.copy(html_path, jp_template_dir)
+
+    # Create the index file.
     index = jp_template_dir.joinpath("index.html")
     index.write_text(
         """

tests/test_app.py

@@ -20,3 +20,12 @@ async def test_notebook_handler(notebooks, jp_fetch):
         # Check that the lab template is loaded
         html = r.body.decode()
         assert "Jupyter Notebook" in html
+
+
+async def test_tree_handler(notebooks, jp_fetch):
+    r = await jp_fetch("tree", "jlab_test_notebooks")
+    assert r.code == 200
+
+    # Check that the tree template is loaded
+    html = r.body.decode()
+    assert "- Tree</title>" in html