Remove the lightning app code (Lightning-AI#20039)

* remove source, tests, docs, workflows

* update checkgroup

* update codeowners

* update workflows

* package setup

* config files

* update

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* remove entry point

* docs

* __main__

* remove store

* leftover store removals

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: awaelchli

.actions/assistant.py

@@ -14,10 +14,8 @@
 import glob
 import logging
 import os
-import pathlib
 import re
 import shutil
-import tarfile
 import tempfile
 import urllib.request
 from distutils.version import LooseVersion
@@ -35,11 +33,6 @@
         "requirements/pytorch/strategies.txt",
         "requirements/pytorch/examples.txt",
     ),
-    "app": (
-        "requirements/app/app.txt",
-        "requirements/app/cloud.txt",
-        "requirements/app/ui.txt",
-    ),
     "fabric": (
         "requirements/fabric/base.txt",
         "requirements/fabric/strategies.txt",
@@ -216,30 +209,6 @@ def distribute_version(src_folder: str, ver_file: str = "version.info") -> None:
         shutil.copy2(ver_template, fpath)
 
 
-def _download_frontend(pkg_path: str, version: str = "v0.0.0"):
-    """Downloads an archive file for a specific release of the Lightning frontend and extracts it to the correct
-    directory."""
-
-    try:
-        frontend_dir = pathlib.Path(pkg_path, "ui")
-        download_dir = tempfile.mkdtemp()
-
-        shutil.rmtree(frontend_dir, ignore_errors=True)
-        # TODO: remove this once lightning-ui package is ready as a dependency
-        frontend_release_url = f"https://lightning-packages.s3.amazonaws.com/ui/{version}.tar.gz"
-        response = urllib.request.urlopen(frontend_release_url)
-
-        file = tarfile.open(fileobj=response, mode="r|gz")
-        file.extractall(path=download_dir)  # noqa: S202
-
-        shutil.move(download_dir, frontend_dir)
-        print("The Lightning UI has successfully been downloaded!")
-
-    # If installing from source without internet connection, we don't want to break the installation
-    except Exception:
-        print("The Lightning UI downloading has failed!")
-
-
 def _load_aggregate_requirements(req_dir: str = "requirements", freeze_requirements: bool = False) -> None:
     """Load all base requirements from all particular packages and prune duplicates.
 
@@ -466,7 +435,7 @@ def pull_docs_files(
                 raise RuntimeError(f"Requesting file '{zip_url}' does not exist or it is just unavailable.")
 
             with zipfile.ZipFile(zip_file, "r") as zip_ref:
-                zip_ref.extractall(tmp)  # noqa: S202
+                zip_ref.extractall(tmp)
 
             zip_dirs = [d for d in glob.glob(os.path.join(tmp, "*")) if os.path.isdir(d)]
             # check that the extracted archive has only repo folder

.azure/app-cloud-e2e.yml

@@ -11,7 +11,6 @@
 /.actions/                  @borda @ethanwharris @justusschock
 /.github/                   @borda @ethanwharris @justusschock
 /.azure/                    @borda @ethanwharris @justusschock
-/.azure/app-cloud-e2e.yml   @awaelchli @ethanwharris @lantiga
 /dockers/                   @borda @ethanwharris @justusschock
 *.yml                       @borda @ethanwharris @justusschock
 
@@ -25,7 +24,6 @@
 /docs/source-pytorch/conf.py                @borda @awaelchli
 /docs/source-pytorch/index.rst              @williamfalcon @lantiga
 /docs/source-pytorch/levels                 @williamfalcon @lantiga
-/docs/source-app/                           @williamfalcon @lantiga @tchaton
 
 # PyTorch Lightning
 /src/lightning/pytorch                      @lantiga @borda @tchaton @awaelchli @justusschock
@@ -36,18 +34,10 @@
 # Lightning Fabric
 /src/lightning/fabric                       @lantiga @borda @tchaton @awaelchli @justusschock
 
-# Lightning App
-/src/lightning/app                          @tchaton @lantiga @awaelchli @ethanwharris
-/src/lightning_app                          @tchaton @lantiga @awaelchli @ethanwharris
-/tests/tests_app                            @tchaton @lantiga @awaelchli @ethanwharris
-/tests/integrations_app                     @tchaton @lantiga @awaelchli @ethanwharris
-/examples/app_*                             @tchaton @lantiga @awaelchli @ethanwharris
-
 /.github/CODEOWNERS                  @williamfalcon
 /SECURITY.md                         @williamfalcon @lantiga
 /README.md                           @williamfalcon @lantiga
 /setup.py                            @williamfalcon @borda
 /src/pytorch_lightning/__about__.py  @williamfalcon @borda
-/src/lightning_app/__about__.py      @williamfalcon @lantiga @borda
 /src/lightning_fabric/__about__.py   @williamfalcon @borda @awaelchli
 /src/*/__setup__.py                  @borda @justusschock

.github/CODEOWNERS

@@ -310,20 +310,6 @@ and the last true master commit is `ccc111` and your first commit is `mmm222`.
   git push -f
   ```
 
-#### How to run an app on the cloud with a local version of lightning
-
-The lightning cloud uses the latest release by default. However, you might want to run your app with some local changes you've made to the lightning framework. To use your local version of lightning on the cloud, set the following environment variable:
-
-```bash
-git clone https://github.com/Lightning-AI/lightning.git
-cd lightning
-pip install -e .
-export PACKAGE_LIGHTNING=1  # <- this is the magic to use your version (not mainstream PyPI)!
-lightning run app app.py --cloud
-```
-
-By setting `PACKAGE_LIGHTNING=1`, lightning packages the lightning source code in your local directory in addition to your app source code and uploads them to the cloud.
-
 ### Bonus Workflow Tip
 
 If you don't want to remember all the commands above every time you want to push some code/setup a Lightning Dev environment on a new VM, you can set up bash aliases for some common commands. You can add these to one of your `~/.bashrc`, `~/.zshrc`, or `~/.bash_aliases` files.

.github/CONTRIBUTING.md

@@ -91,9 +91,7 @@ body:
           <summary>Current environment</summary>
 
         ```
-        #- Lightning Component (e.g. Trainer, LightningModule, LightningApp, LightningWork, LightningFlow):
         #- PyTorch Lightning Version (e.g., 1.5.0):
-        #- Lightning App Version (e.g., 0.5.2):
         #- PyTorch Version (e.g., 2.0):
         #- Python version (e.g., 3.9):
         #- OS (e.g., Linux):

.github/ISSUE_TEMPLATE/1_bug_report.yaml

@@ -25,7 +25,7 @@ runs:
       run: |
         import os, glob
 
-        lut = {'app': 'lightning_app', 'fabric': 'lightning_fabric', 'pytorch': 'pytorch_lightning'}
+        lut = {'fabric': 'lightning_fabric', 'pytorch': 'pytorch_lightning'}
         act_pkg = lut.get('${{inputs.pkg-name}}', 'lightning')
         pkg_sdist = glob.glob('*.tar.gz')[0]
         pkg_wheel = glob.glob('*.whl')[0]