Allow customization of external URLs

[wgu-taylor-payne]

Description:

This adds a getExternalLinkUrl function to the config.js module. This provides a way for external links to be customized/overridden in frontend apps. To customize links, it is required to provide a externalLinkUrlOverrides object as part of the config object defined in env.config.js. This object maps default URLs to custom URLs. Given a URL, the getExternalLinkUrl will check the config object via getConfig for a matching key, and if found, will return the value, which is a custom URL to be used in place of the default URL. If no match is found, the function will return the URL passed in (if it is a valid string).

getExternalLinkUrl can be used when no custom configuration is provided. Also, it will still work in these cases:

1. externalLinkUrlOverrides does not exist in the config object.
2. externalLinkUrlOverrides exists, but is empty.
3. externalLinkUrlOverrides exists, and is not empty, but does not contain a mapping for the URL provided.

In all of these scenarios, the URL passed into the function will be returned to the function. An exception to this is the case where an invalid argument is supplied to the url parameter. In this case the function will fall back to a default value of '#'.

Closes #798

Merge checklist:

• Consider running your code modifications in the included example app within frontend-platform. This can be done by running npm start and opening http://localhost:8080.
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• Verify your commit title/body conforms to the conventional commits format (e.g., fix, feat) and is appropriate for your code change. Consider whether your code is a breaking change, and modify your commit accordingly.

Post merge:

• After the build finishes for the merged commit, verify the new release has been pushed to NPM.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.12%. Comparing base (93bee06) to head (1dc67f9).
Report is 5 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #809      +/-   ##
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+ Coverage   86.79%   87.12%   +0.33%     
==========================================
  Files          48       48              
  Lines        1401     1406       +5     
  Branches      297      300       +3     
==========================================
+ Hits         1216     1225       +9     
+ Misses        172      168       -4     
  Partials       13       13              

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[Copilot]

Pull Request Overview

This PR introduces the getExternalLinkUrl function to allow customization of external URLs by providing a custom mapping via the configuration object. Key changes include:

• Adding the getExternalLinkUrl function in src/config.js with accompanying documentation.
• Introducing thorough tests in src/getExternalLinkUrl.test.js to cover various scenarios.
• Updating relevant documentation in README.md and example usage in ExamplePage.jsx.

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/index.js	Updated re-exports to include getExternalLinkUrl.
src/getExternalLinkUrl.test.js	Added tests to validate getExternalLinkUrl behavior under multiple scenarios.
src/config.js	Introduced getExternalLinkUrl function and updated documentation for external URL customization.
example/ExamplePage.jsx	Demonstrated usage of getExternalLinkUrl in a React example page.
env.config.js	Provided a sample customExternalUrls mapping in the configuration object.
README.md	Updated instructions to guide users on configuring custom external links with getExternalLinkUrl.

Files not reviewed (1)

• .env.development: Language not supported

Comments suppressed due to low confidence (1)

src/config.js:315

• The docstring states that a warning is logged for invalid URLs, but the implementation does not log any warning. Consider updating the documentation or adding the warning logging for consistency.

 * If the input URL is invalid, a warning is logged and '#' is returned.

[sarina]

I'm not going to be able to provide a comprehensive review on this PR. But I do wonder why the values in .env.development have changed.

[wgu-taylor-payne]

The ports in .env.development were compatible with devstack rather than tutor. I've updated them to be compatible with a default tutor dev environment.

[arbrandes]

I love the included documentation and tests, thank you! The code looks great, too.

I only raised a matter of function/object naming, which we should discuss before merging.

[brian-smith-tcril]

Overall this looks great! Would you be able to move the .env changes and the README changes that aren't related to URL overrides to a separate PR? I think they're valuable changes but I'd prefer to keep this PR targeted to the one task.

[brian-smith-tcril]

Thank you so much for putting this together!

LGTM!

[arbrandes]

Looks great! 👍🏼