Chef CI/CD Docs (#20711)

* Update README and make bundle generic and gating

* Format

* Format

* More semantic naming

* Spelling

* Spelling

* Restyle again

examples/chef/README.md

@@ -9,9 +9,9 @@ Chef uses the shell app a starting point, but processes the data model defined
 on ZAP files during build time. This procedure is handled by its unified build
 script: `chef.py`.
 
-As it incorporates the processing of ZAP files as part of the build process, it
-does not use `zzz_generated`, but rather places the auto-generated zap artifacts
-under its `out` temporary folder.
+When processing ZAP files as part of the build process, Chef places the
+auto-generated zap artifacts under its `out` temporary folder. Chef uses
+artifacts from `zzz_generated` for CI/CD.
 
 All device types available (.zap files) are found inside the `devices` folder.
 
@@ -83,9 +83,142 @@ All device types available (.zap files) are found inside the `devices` folder.
 
 All CI jobs for chef can be found in `.github/workflows/chef.yaml`.
 
-These jobs use a platform-specific image with base `chip-build`.
+These jobs use a platform-specific image with base `chip-build`. Such images
+contain the toolchain for the respective platform under `/opt`.
 
-CI jobs call chef with the options `--ci -t <PLATFORM>`. The `--ci` option will
-execute builds for all devices specified in `cicd_config["ci_allow_list"]`
-defined in `chef.py` (so long as these devices are also in `/devices`) on the
+CI jobs call chef with the options `--ci -t $PLATFORM`. The `--ci` option will
+execute builds for all devices specified in `ci_allow_list` defined in
+`cicd_config.json` (so long as these devices are also in `/devices`) on the
 specified platform.
+
+CI jobs also call the function `bundle_$PLATFORM` at the end of each example
+build. This function should copy or move build output files from the build
+output location into `_CD_STAGING_DIR`. Typically, the set of files touched is
+the minimal set of files needed to flash a device. See the function
+`bundle_esp32` for reference.
+
+### Adding a platform
+
+First, implement a `bundle_$PLATFORM` function.
+
+Next, ensure that the examples in `ci_allow_list` build in a container using the
+relevant platform image. You can simulate the workflow locally by mounting your
+CHIP repo into a container and executing the CI command:
+
+```shell
+docker run -it --mount source=$(pwd),target=/workspace,type=bind connectedhomeip/chip-build-$PLATFORM:$VERSION
+```
+
+In the container:
+
+```shell
+chown -R $(whoami) /workspace
+cd /workspace
+source ./scripts/bootstrap.sh
+source ./scripts/activate.sh
+./examples/chef/chef.py --ci -t $PLATFORM
+```
+
+Once you are confident the CI examples build and bundle in a container, add a
+new job to the chef workflow.
+
+Replace all instances of `$PLATFORM` with the new platform. Replace `$VERSION`
+with the image version used in the rest of the workflows, or update the image
+version for all images in the workflow as needed.
+
+```yaml
+chef_$PLATFORM:
+    name: Chef - $PLATFORM CI Examples
+    runs-on: ubuntu-latest
+    if: github.actor != 'restyled-io[bot]'
+
+    container:
+        image: connectedhomeip/chip-build-$PLATFORM:$VERSION
+        options: --user root
+
+    steps:
+        - uses: Wandalen/wretry.action@v1.0.15
+          name: Checkout
+          with:
+              action: actions/checkout@v3
+              with: |
+                  token: ${{ github.token }}
+              attempt_limit: 3
+              attempt_delay: 2000
+        - name: Checkout submodules
+          run: scripts/checkout_submodules.py --shallow --platform $PLATFORM
+        - name: Bootstrap
+          timeout-minutes: 10
+          run: scripts/build/gn_bootstrap.sh
+        - name: CI Examples $PLATFORM
+          shell: bash
+          run: |
+              ./scripts/run_in_build_env.sh "./examples/chef/chef.py --ci -t $PLATFORM"
+```
+
+## CD
+
+Once CI is enabled for a platform, the platform may also be integrated into
+`integrations/cloudbuild/`, where chef builds are defined in `chef.yaml`. See
+the `README` in this path for more information.
+
+Note that the image used in `chef.yaml` is `chip-build-vscode`. See
+`docker/images/chip-build-vscode/Dockerfile` for the source of this image. This
+image is a combination of the individual toolchain images. Therefore, before a
+platform is integrated into chef CD, the toolchain should be copied into
+`chip-build-vscode` and `chef.yaml` should be updated to use the new image
+version.
+
+Finally, add the new platform to `cd_platforms` in `cicd_config.json`. The
+configuration should follow the following schema:
+
+```json
+"$PLATFORM": {
+    "output_archive_prefix_1": ["option_1", "option_2"],
+    "output_archive_prefix_2": [],
+}
+```
+
+Take note of the configuration for `linux`:
+
+```json
+"linux": {
+    "linux_x86": ["--cpu_type", "x64"],
+    "linux_arm64_ipv6only": ["--cpu_type", "arm64", "--ipv6only"]
+},
+```
+
+This will produce output archives prefixed `linux_x86` and
+`linux_arm_64_ipv6only` and will append the respective options to each build
+command for these targets.
+
+To test your configuration locally, you may employ a similar strategy as in CI:
+
+```shell
+docker run -it --mount source=$(pwd),target=/workspace,type=bind connectedhomeip/chip-build-vscode:$VERSION
+```
+
+In the container:
+
+```shell
+chown -R $(whoami) /workspace
+cd /workspace
+source ./scripts/bootstrap.sh
+source ./scripts/activate.sh
+./examples/chef/chef.py --build_all --keep_going
+```
+
+You may also use the Google Cloud Build local builder as detailed in the
+`README` of `integrations/cloudbuild/`.
+
+## Adding new devices
+
+To add new devices for chef:
+
+-   Execute `python sample_app_util.py zap <zap_file> --rename-file` to rename
+    the example and place the new file in `examples/chef/devices`.
+    -   See the `README` in `examples/chef/sample_app_util/` for more info.
+-   Execute `scripts/tools/zap_regen_all.py`, commit `zzz_generated` and
+    `examples/chef/devices`.
+    -   This is gated by the workflow in `.github/workflows/zap_templates.yaml`.
+-   All devices added to the repository are built in CD.

examples/chef/chef.py

@@ -134,18 +134,19 @@ def bundle(platform: str, device_name: str) -> None:
         platform: The platform to bundle.
         device_name: The example to bundle.
     """
+    bundler_name = f"bundle_{platform}"
     matter_file = f"{device_name}.matter"
     zap_file = os.path.join(_DEVICE_FOLDER, f"{device_name}.zap")
     flush_print(f"Bundling {platform}", with_border=True)
     flush_print(f"Cleaning {_CD_STAGING_DIR}")
     shutil.rmtree(_CD_STAGING_DIR, ignore_errors=True)
     os.mkdir(_CD_STAGING_DIR)
-    if platform == "linux":
-        bundle_linux(device_name)
-    elif platform == "nrfconnect":
-        bundle_nrfconnect(device_name)
-    elif platform == "esp32":
-        bundle_esp32(device_name)
+    flush_print(f"Checking for {bundler_name}")
+    chef_module = sys.modules[__name__]
+    if hasattr(chef_module, bundler_name):
+        flush_print(f"Found {bundler_name}")
+        bundler = getattr(chef_module, bundler_name)
+        bundler(device_name)
     else:
         flush_print(f"No bundle function for {platform}!")
         exit(1)