Add GitHub PRs to the Static Analysis integrations (#20981)

* Add GitHub PRs to the integrations

* Update _index.md

* Update content/en/continuous_integration/static_analysis/_index.md

Co-authored-by: Mark Azer <[email protected]>

* Update _index.md

* Write feature overview for GitHub source code management

* Sketch in content outline

* Add page to the TOC

* Add section on configuring a GitHub App

* Add product shot

* Update product screenshot

* Flesh out GitHub App instructions

* Finish first draft of instructions

* Update content/en/static_analysis/github_source_code_management.md

Co-authored-by: Mark Azer <[email protected]>

* Update content/en/static_analysis/github_source_code_management.md

Co-authored-by: Mark Azer <[email protected]>

* Update content/en/static_analysis/github_source_code_management.md

Co-authored-by: Mark Azer <[email protected]>

* Update content/en/static_analysis/github_source_code_management.md

Co-authored-by: Mark Azer <[email protected]>

* Update content/en/static_analysis/github_source_code_management.md

Co-authored-by: Mark Azer <[email protected]>

* Integrate feedback

* Rename file

* Update URL

* Integrate feedback

* Update identifier

* Update _index.md

* Tweak instructions

* Integrate feedback

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Update content/en/static_analysis/github_pull_requests.md

Co-authored-by: Austin Lai <[email protected]>

* Spacing Nit

---------

Co-authored-by: Mark Azer <[email protected]>
Co-authored-by: Austin Lai <[email protected]>

config/_default/menus/menus.en.yaml

@@ -2708,6 +2708,11 @@ main:
     parent: static_analysis
     identifier: static_analysis_github_actions
     weight: 103
+  - name: GitHub Pull Requests
+    url: static_analysis/github_pull_requests
+    parent: static_analysis
+    identifier: static_analysis_github_prs
+    weight: 103
   - name: Quality Gates
     url: quality_gates/
     pre: ci

content/en/static_analysis/_index.md

@@ -39,12 +39,17 @@ Using Static Analysis provides organizations with the following benefits:
 
 ## Integrations
 
-### CI Providers
+### CI providers
 {{< whatsnext desc="With Static Analysis, you can integrate feedback on code reviews for various languages in any CI platform provider of choice. See the documentation for information about the following integrations:">}}
     {{< nextlink href="continuous_integration/static_analysis/circleci_orbs" >}}CircleCI Orbs{{< /nextlink >}}
     {{< nextlink href="continuous_integration/static_analysis/github_actions" >}}GitHub Actions{{< /nextlink >}}
 {{< /whatsnext >}}
 
+### Source code management
+{{< whatsnext desc="During code reviews, source code management (SCM) integrations check for Static Analysis violations in pull requests for repos that have at least one ruleset applied. Violations are flagged with a comment on the relevant line of code. Certain violations also include suggested changes that can be applied directly in the UI of the SCM tool." >}}
+    {{< nextlink href="static_analysis/github_pull_requests" >}}GitHub Pull Requests{{< /nextlink >}}
+{{< /whatsnext >}}
+
 ### IDEs
 {{< whatsnext desc="With Static Analysis, you can get real-time feedback as you edit a file in your Integrated Development Environment (IDE). See the documentation for information about the following integrations:">}}
     {{< nextlink href="developers/ide_integrations/idea/" >}}Datadog Plugin for IntelliJ IDEA{{< /nextlink >}}

content/en/static_analysis/github_pull_requests.md

@@ -0,0 +1,77 @@
+---
+title: GitHub Pull Requests
+kind: documentation
+description: Learn how to use Static Analysis in GitHub pull requests.
+further_reading:
+- link: "/integrations/github/"
+  tag: "Documentation"
+  text: "Learn about the GitHub integration"
+- link: "/static_analysis/"
+  tag: "Documentation"
+  text: "Learn about Static Analysis"
+---
+
+## Overview
+
+Static Analysis can automatically flag rule violations in pull requests on GitHub. To configure the [GitHub integration][2] to include Static Analysis features, see [the setup instructions](#set-up-static-analysis-for-github-pull-requests).
+
+During code reviews on GitHub, the integration checks for Static Analysis violations in pull requests for repos that have at least one ruleset applied. Violations are flagged with a review comment on the relevant line of code.
+
+{{< img src="ci/static-analysis-pr-comment-example.png" alt="Example of a Static Analysis comment on a pull request" style="width:90%;" >}}
+
+The comment includes the name, ID, severity, category, and description of the violation. Certain violations also include suggested changes that can be applied directly in the GitHub UI.
+
+## Set up Static Analysis for GitHub pull requests
+
+### Enable Static Analysis on Datadog
+
+To use Datadog Static Analysis, add the appropriate configuration files to your repository, as described in the [setup instructions][1].
+
+### Configure a GitHub App
+
+To use Static Analysis on GitHub, you can do one of the following:
+
+- Create a GitHub App in Datadog.
+- Update an existing GitHub App, if you have already created one in Datadog.
+
+The permissions you grant to the GitHub App determine which [GitHub integration][2] features are available for setup.
+
+#### Create and install a GitHub App
+
+1. In Datadog, navigate to [**Integrations > GitHub Applications > Add New GitHub Application**][3].
+1. Fill out any required details, such as the GitHub organization name.
+1. Under **Select Features**, check the **Static Analysis: Pull Request Review Comments** box.
+1. Under **Edit Permissions**, verify that the **Pull Requests** permission is set to **Read & Write**.
+1. Click **Create App in GitHub**.
+1. Enter a name for your app, and submit it.
+1. Click **Install GitHub App**.
+1. Choose which repositories the app should be installed into, then click **Install & Authorize**.
+
+{{< img src="ci/static-analysis-install-github-app.png" alt="GitHub App installation screen" style="width:50%;" >}}
+
+#### Update an existing GitHub App
+
+1. In Datadog, navigate to [**Integrations > GitHub Applications**][5], and search for the GitHub App you want to use for Static Analysis.
+{{< img src="ci/static-analysis-existing-github-app.png" alt="Example of a Static Analysis comment on a pull request" style="width:90%;" >}}
+1. On the **Features** tab, look at the **Static Analysis: Pull Request Comments** section to determine whether your GitHub App needs additional permissions. If so, click **Update permissions in GitHub** to edit the app settings.
+1. Under **Repository permissions**, set the **Pull Requests** access to **Read and write**.
+{{< img src="ci/static-analysis-pr-read-write-permissions.png" alt="The dropdown for the pull request read and write permission" style="width:90%;" >}}
+1. Under the **Subscribe to events** heading, check the **Pull request** box.
+{{< img src="ci/static-analysis-pr-review-comment.png" alt="The checkbox for the pull request review comment permission" style="width:90%;" >}}
+
+### Enable Static Analysis PR comments for your repositories
+
+1. In Datadog, navigate to [**CI Settings** > **Static Analysis Settings**][4].
+1. Click the toggle switch next to a given repository to enable **GitHub Comments**. In the example below, comments are enabled for the `demo-static-analysis-gates` repository.
+
+{{< img src="ci/static-analysis-github-comments.png" alt="Example of a Static Analysis comment on a pull request" style="width:100%;" >}}
+
+## Further Reading
+
+{{< partial name="whats-next/whats-next.html" >}}
+
+[1]: /static_analysis#setup
+[2]: /integrations/github/
+[3]: https://app.datadoghq.com/integrations/github/add
+[4]: https://app.datadoghq.com/ci/settings/static-analysis
+[5]: https://app.datadoghq.com/integrations/github/configuration