Document possible Skip actions.

doc/eng_sys_checks.md

@@ -1,11 +1,34 @@
 # Azure SDK for Python - Engineering System
 
-* [Target a specific package](#targeting-a-specific-package-at-build-time)
-* [Skip a tox test environment](#skipping-a-tox-test-environment-at-queue-time)
-* [Analyze Checks](#analyze-checks)
-* [PR Validation Checks](#pr-validation-checks)
-* [Nightly CI Checks](#nightly-ci-checks)
-* [Nightly Live Checks](#nightly-live-checks)
+- [Azure SDK for Python - Engineering System](#azure-sdk-for-python---engineering-system)
+  - [Targeting a specific package at build time](#targeting-a-specific-package-at-build-time)
+  - [Skipping a tox test environment at queue time](#skipping-a-tox-test-environment-at-queue-time)
+  - [Skipping entire sections of builds](#skipping-entire-sections-of-builds)
+  - [Environment variables important to CI](#environment-variables-important-to-ci)
+  - [Analyze Checks](#analyze-checks)
+    - [MyPy](#mypy)
+    - [Pylint](#pylint)
+    - [Bandit](#bandit)
+    - [ApiStubGen](#apistubgen)
+    - [black](#black)
+      - [Opt-in to formatting validation](#opt-in-to-formatting-validation)
+      - [Running locally](#running-locally)
+    - [Change log verification](#change-log-verification)
+  - [PR Validation Checks](#pr-validation-checks)
+    - [PR validation tox test environments](#pr-validation-tox-test-environments)
+      - [whl](#whl)
+      - [sdist](#sdist)
+      - [depends](#depends)
+  - [Nightly CI Checks](#nightly-ci-checks)
+      - [Latest Dependency Test](#latest-dependency-test)
+      - [Minimum Dependency Test](#minimum-dependency-test)
+      - [Regression Test](#regression-test)
+      - [Autorest Automation](#autorest-automation)
+        - [Opt-in to autorest automation](#opt-in-to-autorest-automation)
+        - [Running locally](#running-locally-1)
+  - [Nightly Live Checks](#nightly-live-checks)
+    - [Running Samples](#running-samples)
+
 
 There are various tests currently enabled in Azure pipeline for Python SDK and some of them are enabled only for nightly CI checks. We also run some static analysis tool to verify code completeness, security and lint check.
 
@@ -46,6 +69,36 @@ This is an example setting of that narrows the default set from `whl, sdist, dep
 
 Any combination of valid valid tox environments will work. Reference either this document or the file present at `eng/tox/tox.ini` to find what options are available.
 
+## Skipping entire sections of builds
+
+In certain cases,release engineers may want to disable `APIView` checks prior to releasing. Engineers who need this capability should first clear it with their lead, then set the following build time variable.
+
+- Create variable named `Skip.CreateApiReview`
+  - Set variable valuable to `true`
+
+This is the most useful skip, but the following skip variables are also supported. Setting the variable value to `true` should be used for all of the below.
+
+- `Skip.Analyze`
+  - Skip the `analyze` job entirely.
+- `Skip.Test`
+  - Skip the `test` jobs entirely.
+- `Skip.TestConda`
+  - Skip the `conda test` jobs entirely.
+- `Skip.ApiStubGen`
+  - Entirely omits API stub generation within `build` job.
+- `Skip.VerifySdist`
+  - Omit `twine check` of source distributions in `build` job.
+- `Skip.VerifyWhl`
+  - Omit `twine check` of wheels in `build` job.
+- `Skip.Bandit`
+  - Omit `bandit` checks in `analyze` job.
+- `Skip.Pylint`
+  - Omit linting checks in `analyze` job.
+- `Skip.BreakingChanges`
+  - Don't verify if a changeset includes breaking changes.
+- `Skip.MyPy`
+  - Omit `mypy` checks in `analyze` job.
+
 ## Environment variables important to CI
 
 There are a few differences from a standard local invocation of `tox <env>`. Primarily, these differences adjust the checks to be friendly to parallel invocation. These adjustments are necessary to prevent random CI crashes.