Add stack outputs section to GitHub Actions CI/CD guide

[joeduffy]

Closes #10175

What this PR does

Adds a new "Stack outputs" section to the GitHub Actions CI/CD guide, documenting how to access Pulumi stack outputs in downstream workflow steps. This has been a recurring community request—the issue was opened in October 2023 based on feedback from July 2023.

Changes

Adds a new top-level section between "Pull Request Flow" and "Configuration" covering two approaches:

Using the pulumi/actions action: The action already exposes each stack output as a named step output via GitHub Actions' steps.<id>.outputs.<output-name> mechanism. The new section documents this with a working YAML workflow example and language-specific snippets (TypeScript, Python, Go, C#) showing how to export the output from Pulumi code.

Using the Pulumi CLI directly: For cases where the pulumi/actions action is not used for a given step, documents how to capture pulumi stack output <key> and pulumi stack output --json into $GITHUB_OUTPUT and use the result in subsequent steps.

The section also includes a warning callout about sensitive output values, pointing readers to suppress-outputs: true and GitHub Encrypted Secrets.

Testing

Markdown lint passed (0 errors across 1736 files).

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🧠 This PR was created by minime on behalf of @joeduffy.

[claude]

Docs Review

Scope: Reviewed the added "Stack outputs" section in content/docs/iac/guides/continuous-delivery/github-actions.md (113 lines added).

Overall this is a well-structured, useful addition that addresses a real community need (issue #10175). The content is accurate, clearly organized into two approaches (action vs CLI), and includes appropriate language-specific examples. A few items to consider:

Issues

1. Unused import in TypeScript example (line 696): The snippet imports @pulumi/pulumi but never uses it — the stack output uses JavaScript's native export const syntax. While the // ... resource definitions ... comment implies the import would be used in a full program, the review criteria call for realistic, verifiable examples. Consider either removing the import or adding a brief comment like // Used by resource definitions below to make the intent explicit.

2. Incomplete "all outputs as JSON" example (lines 781–788): The JSON example shows how to capture all outputs but does not show how to access individual values from the JSON in a subsequent step. Readers unfamiliar with GitHub Actions fromJSON() may not know how to proceed. Consider adding a follow-up step showing usage, e.g.:

   - name: Use a JSON output
     run: echo "Deployed to ${{ fromJSON(steps.stack.outputs.outputs).url }}"

3. Heading capitalization (line 685): ### Using the pulumi/actions GitHub Action — the subsection heading uses lowercase for pulumi/actions, which is correct since it's a code reference, but consider formatting it as `pulumi/actions` with backticks for consistency with how it appears in the body text. Same applies to line 762: ### Using the Pulumi CLI directly.

Minor / optional

• Line 683: The introductory sentence is quite long (46 words). Consider splitting it for readability, e.g., ending the first sentence after "workflow" and starting a new sentence with "This is useful when..."
• Line 760: The linked GitHub Actions documentation covers passing information between jobs broadly but does not specifically address special characters in output names. Consider linking to a more targeted section if one exists, or clarifying that the reader should search within that page.

What looks good

• Correct use of the chooser/choosable shortcodes for multi-language examples.
• The warning callout about sensitive outputs is well-placed and actionable.
• The internal link to /docs/iac/concepts/stacks/#outputs is valid.
• Section placement between "Pull Request Flow" and "Configuration" is logical.
• All code blocks have language specifiers.

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Mention me (@claude) if you'd like additional reviews or help with fixes.

[pulumi-bot]

Your site preview for commit 827cabb is ready! 🎉

http://www-testing-pulumi-docs-origin-pr-17957-827cabbf.s3-website.us-west-2.amazonaws.com.

[joeduffy]

Thanks for the detailed review! I've addressed all the feedback in 59211e2:

• TypeScript import: Removed the unused import * as pulumi line from the TypeScript snippet. The export const syntax stands alone cleanly.
• H3 heading: Added backticks to `pulumi/actions` in the heading for consistency with how it appears in body text.
• JSON outputs example: Added a follow-up step demonstrating fromJSON(steps.stack.outputs.outputs).url so readers know how to access individual values after capturing the JSON blob.
• Intro sentence: Removed the parentheses construction and restructured the sentence so it flows more naturally without the em-dash or parenthetical detour.

[pulumi-bot]

Your site preview for commit 59211e2 is ready! 🎉

http://www-testing-pulumi-docs-origin-pr-17957-59211e2b.s3-website.us-west-2.amazonaws.com.