feat(externals): add flag to not throw if externals semver have mismatch

[Matthew-Mallimo]

Description

Adds a new flag, DANGEROUSLY_ACCEPT_BREAKING_EXTERNALS, that when set true, will log a warning instead of throwing an error whenever a mismatch in version for externals is detected.

Motivation and Context

When upgrading versions of providedExternals set by your route module, it can be frustrating because one-app will fail to start up because it throws an error when mismatching external versions are found. If the app is already running, module map polling will fail.

The DANGEROUSLY_ACCEPT_BREAKING_EXTERNALS flag will prevent this from happening by logging a warning instead of throwing an error.

This is a dangerous flag to set because mismatching versions can cause unexpected behaviors for modules, and should only be used during a transition of external versions.

How Has This Been Tested?

unit tested

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (adding or updating documentation)
• Dependency update
• Security update

Checklist:

• My change requires a change to the documentation and I have updated the documentation accordingly.
• These changes should be applied to a maintenance branch.
• This change requires cross browser checks.
• Performance tests should be ran against the server prior to merging.
• This change impacts caching for client browsers.
• This change impacts HTTP headers.
• This change adds additional environment variable requirements for One App users.
• I have added the Apache 2.0 license header to any new files created.

What is the Impact to Developers Using One App?

[github-actions]

📊 Bundle Size Report

file name	size on disk	gzip
app.js	311.5KB	91.4KB
runtime.js	15.6KB	5.5KB
vendors.js	129.1KB	40KB
app~vendors.js	421.5KB	109.7KB
service-worker-client.js	17.1KB	5.3KB
legacy/app.js	332.6KB	96.8KB
legacy/runtime.js	15.6KB	5.5KB
legacy/vendors.js	189.3KB	51.7KB
legacy/app~vendors.js	444.6KB	115.5KB
legacy/service-worker-client.js	17.6KB	5.5KB

Generated by 🚫 dangerJS against 8c0acbc

[10xLaCroixDrinker]

How Has This Been Tested?

unit tested

This requires more than unit tests. What scenarios have you run in a development environment?

[Matthew-Mallimo]

How Has This Been Tested?

unit tested

This requires more than unit tests. What scenarios have you run in a development environment?

I have also run this locally. Tested:

• Starting one-app with externals semver mismatch - Flag off - Fails to start
• Starting one-app with externals semver mismatch - Flag on - Starts up with no issues
• Deploying a module with semver mismatch while one-app is running - Flag off - module map polling fails
• Deploying a module with semver mismatch while one-app is running - Flag on - Module map continues to poll successfully while logging the warning to the console.