Optimize lsp server error message

CHANGELOG.md

@@ -3,9 +3,11 @@
 ### `@krassowski/jupyterlab-lsp 3.7.1` (unreleased)
 
 - bug fixes:
-  - fix rename shortcut registration in file browser ([#614])
+  - fix rename shortcut registration in file editor ([#614])
+  - add a note on manually enabling backend extension ([#621], thanks @icankeep)
 
 [#614]: https://github.com/krassowski/jupyterlab-lsp/pull/614
+[#621]: https://github.com/krassowski/jupyterlab-lsp/pull/621
 
 ### `jupyter-lsp 1.3.0` (2021-06-02)
 

packages/jupyterlab-lsp/src/errors.tsx

@@ -50,7 +50,9 @@ export const SERVER_EXTENSION_404 = (
     <p>
       Please ensure that <code>jupyter server extension list</code> includes
       jupyter-lsp and that it is enabled. If it is enabled please try to restart
-      JupyterLab.
+      JupyterLab. If the server extension is installed but not enabled and all
+      other suggestions listed above failed try the following:
+      <code>jupyter server extension enable --user --py jupyter_lsp</code>
     </p>
   </div>
 );

requirements/dev.txt

@@ -8,3 +8,4 @@ pytest-cov
 ruamel.yaml
 robotframework-lint >=1.1
 robotframework >=3.2
+types-six

requirements/lint.yml

@@ -5,9 +5,12 @@ channels:
   - nodefaults
 
 dependencies:
+  - pip
   - black
   - isort
   - mypy
   - robotframework-lint >=1.1
   - robotframework >=4
   - pytest-tornasync
+  - pip:
+      - types-six