refactor(LSG): get rid of async in handlers; extract shared logic to base classes

[ianshade]

About the Contributor

This pull request is posted on behalf of TV 2 Norge

Type of Contribution

This is a:

Code improvement

Current Behavior

New Behavior

• Event handlers for document updates are no longer asynchronous, which should make the code less prone to race conditions
• Throttling (batching) of document update events is moved to the CollectionBase class
• Repeating collection (publication) subscription and observer setup/teardown logic is extracted to the PublicationCollection class
• Subscription to collection handlers by other collection handlers and topics is now performed in the init methods of those handlers and topics instead of all happening in LiveStatusServer
• Large update methods are broken down into smaller ones, per each collection (tradeoff: a little extra boilerplate, but less indentation and better type safety)
• Subscription to collection handlers is done more selectively - only change of selected properties trigger update events
• Some redundant properties are removed (observerName)
• In a few cases, slight changes of which collection handlers are subscribed to in order to get certain information (rundownId)
• Simplified the initial no-data flow and empty array handling

Testing

• I have added one or more unit tests for this PR
• I have updated the relevant unit tests
• No unit test changes are needed for this PR

Affected areas

This PR affects the Live Status Gateway

Time Frame

Not urgent, but it would be nice to have in release 52

Other Information

These changes were so far tested only on release50, with release51 LSG

Status

• PR is ready to be reviewed.
• The functionality has been tested by the author.
• Relevant unit tests has been added / updated.
• Relevant documentation (code comments, system documentation) has been added / updated.

[codecov]

Codecov Report

Attention: Patch coverage is 53.27103% with 150 lines in your changes missing coverage. Please review.

Project coverage is 56.79%. Comparing base (054dcb1) to head (3252531).
Report is 13 commits behind head on release52.

Files with missing lines	Patch %	Lines
packages/live-status-gateway/src/wsHandler.ts	14.14%	71 Missing and 14 partials ⚠️
...ckages/live-status-gateway/src/helpers/equality.ts	6.81%	39 Missing and 2 partials ⚠️
...ages/live-status-gateway/src/topics/adLibsTopic.ts	75.00%	14 Missing ⚠️
...e-status-gateway/src/topics/activePlaylistTopic.ts	84.21%	8 Missing and 1 partial ⚠️
...es/live-status-gateway/src/topics/segmentsTopic.ts	96.42%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##           release52    #1367      +/-   ##
=============================================
+ Coverage      56.48%   56.79%   +0.30%     
=============================================
  Files            401      391      -10     
  Lines          72257    71672     -585     
  Branches        4170     4391     +221     
=============================================
- Hits           40816    40706     -110     
+ Misses         31204    30799     -405     
+ Partials         237      167      -70     

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