February 2022 - OpenScienceLab Documentation

Welcome to the February 2022 OpenSARLab Update!

Ubuntu 20.04.3 LTS¶

There are now JupyterLab profiles available alongside the Classic Jupyter Notebook profiles. JupyterLab comes with many more features than Classic Jupyter Notebook (see the JupyterLab Docs) for more information.
Classic Jupyter Notebook profiles will remain active for 1 month before being deprecated on March 7th.

matplotlib notebook has been replaced with matplotlib widget for interactive matplotlib plots.
- matplotlib notebook will not work in JupyterLab, whereas matplotlib widget works in both JupyterLab and Classic Jupyter Notebook.

The url-widget package is now installed, allowing notebook Python kernels access to the current notebook’s URL.
- This is useful for dynamically creating links to files and notebooks in OpenSARlab, and it is used in the kernel checking code at the beginning of ASF provided notebooks.

JupyterLab comes with a built-in memory monitor, replacing the jupyter-resource-usage extension.
- The new memory monitor can be found in the status bar at the bottom of the JupyterLab screen.

The mamba package manager is now available in OpenSARlab.
- Mamba is a multi-threaded “reimplementation of the conda package manager in C++.”
  - It creates environments much more quickly than conda.
The opensarlab-envs repo has been updated to use mamba.

mamba gator provides a GUI for managing conda/mamba environments that is accessible in JupyterLab.
- Access mamba gator by selecting the Conda Packages Manager from the Settings menu.

The spellchecker extension is installed.
- It checks spelling in markdown cells.
- The language may be changed in the status bar at the bottom of the screen.

We have added some custom JupyterLab extensions to duplicate custom features previously added in OpenSARlab for Jupyter Notebooks.
- opensarlab-profile-label provides the name of the current OpenSARlab profile in the topbar.
- opensarlab-doc-link provides a link to the OpenSARlab documentation in the topbar.
- opensarlab-controlbtn provides a Shutdown and Logout Page button in the topbar.
- opensarlab-notifications provides similar functionality to the popup notifications used in the OpenSARlab Classic Jupyter Notebook profiles.

The following bullet points cover code changes you may need to make to your notebooks for them to work in JupyterLab

note: These changes are backwards compatible and updated notebooks will still run in Jupyter Notebook.

note: All ASF notebooks have already been updated.

The javascript variable Jupyter.notebook.kernel does not exist in JupyterLab.
- If you need a Python variable containing a notebook’s current Python kernel, run:
  - env = !echo $CONDA_PREFIX
The javascript variable window.location does not exist in JupyterLab
- If you need the current url of your Jupyter workspace, install the url-widget package in your conda environment and use it to retrieve the url:

# In one cell
import url_widget as url_w
notebook_url = url_w.URLWidget()
display(notebook_url)

# In a following cell
notebook_url = notebook_url.value

%matplotlib notebook does not work for interactive plotting in JupyterLab
- Instead, use: %matplotlib widget
asf_notebook.py is deprecated and has been replaced with opensarlab-lib: https://github.com/ASFOpenSARlab/opensarlab-lib
- asf_notebook.py still works (with deprecation warnings) but it is not being maintained.
- Install opensarlab-lib with one of the following commands:
  - python -m pip install opensarlab-lib
  - conda install -n <environment_name> -c conda-forge opensarlab-lib
- Alternatively, you may add environment.yml as a dependency and use it instead.