chore(samples): Snippet Generating System (part 1) (#199)

* chore(samples): Snippet Generating System

Preparing the SGS (Snippet Generating System) script
to handle the burden of duplicated code in the samples.

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Anthonios Partheniou <[email protected]>

packages/google-cloud-compute/samples/README.md

@@ -0,0 +1,53 @@
+# Code samples for the Compute Engine library
+
+In this folder you can find the source code for the code samples used throughout the 
+[public documentation](https://cloud.google.com/compute/docs/) of Google Compute Engine.
+
+The samples can be found in the `snippets` folder, where they are organized to mimic the
+structure of the public documentation. Files that are saved there are generated by the `sgs.py`
+script from pieces found in `ingredients` and `recipes`. This way, one piece of code can be easily
+included in multiple snippets and updating the code requires less work.
+
+## Working with the SGS
+
+SGS (Snippet Generating System) works by scanning the `recipes` folder, finding all files
+and filling them with pieces of code found in `ingredients`. The folder structure of `recipes` is 
+reconstructed in the `snippets` folder.
+
+### Adding new sample
+
+To create a new sample, just prepare a new file in one of the `recipes` subfolders. The SGS will pick it up 
+automatically when you run it, by executing `python3 sgs.py generate` in this (`samples/`) directory.
+
+### Removing/moving a sample
+
+To remove or move a sample, you need to simply modify the `recipes` folder to match your desired structure, then delete
+the generated snippet from the `snippets` directory. The SGS script will create the snippet in the new location next 
+time you run `python3 sgs.py generate`.
+
+### Interacting with GIT
+
+SGS will not interact with Git repository in any way. All changes made by the script need to be committed manually - 
+preferably in the same commit as the update to the source files.
+
+## Preparing an ingredient
+To add a new ingredient, create a new `.py` file with the code you want to later use in the snippets. Mark the beginning
+of the code you want to include with `# <INGREDIENT name>` and the end with `# </INGREDIENT>`. 
+
+Please leave the imports required by this ingredient **OUTSIDE** the area marked with ingredient comments. The SGS 
+script will automatically collect all the required imports and put them in the final snippet in the right place and in
+right order.
+
+## Preparing a recipe
+Each recipe is a file located in the `recipes` folder. It should have the `.py` extension and should be a valid Python 
+script. Each recipe has to have an `# <IMPORTS/>` line and at least one `# <INGREDIENT name/>` line. 
+Apart from those restrictions, the contents of the file can be whatever you want.
+
+The SGS will copy the recipe file to the destination folder in `snippets` and replace the `# <IMPORTS/>` and 
+`# <INGREDIENT name/>` lines with the `import` statements required by the used ingredients and with the ingredient
+body.
+
+### Regions
+You should use `# <REGION region_name>` and `# </REGION region_name>` lines to indicate where start and end
+of a region should be placed in the generated snippet. Those lines will be simply replaced with the proper 
+`START region_name` and `END region_name` lines.

packages/google-cloud-compute/samples/noxfile_config.py

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+#  Copyright 2022 Google LLC
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+TEST_CONFIG_OVERRIDE = {
+    # Tests in test_sample_default_values.py require separate projects to not interfere with each other.
+    "gcloud_project_env": "BUILD_SPECIFIC_GCLOUD_PROJECT",
+}

packages/google-cloud-compute/samples/snippets/requirements-test.txt → packages/google-cloud-compute/samples/requirements-test.txt

@@ -1,4 +1,4 @@
 pytest==7.0.1
 flaky==3.7.0
 google-cloud-storage==2.1.0; python_version == '3.6'
-google-cloud-storage==2.1.0; python_version >= '3.7'
+google-cloud-storage==2.1.0; python_version >= '3.7'

packages/google-cloud-compute/samples/requirements.txt

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+isort==5.10.1
+black==22.1.0
+google-cloud-compute==1.0.0