TTS | Introduce markInProgress

[sudiksha27]

General

Before this PR: There was no way to mark a transaction in progress.

After this PR: Introduces markInProgress in TransactionService for transactions4. Does not perform any wiring. The basic implementation for multi endpoint has been kept same as putUnlessExists by default.

Priority: First pass before end of this would be great

Concerns / possible downsides (what feedback would you like?): Does the design make sense

Is documentation needed?: Docs added

Compatibility

~Does this PR create any API breaks (e.g. at the Java or HTTP layers) - if so, do we have compatibility?:~

~Does this PR change the persisted format of any data - if so, do we have forward and backward compatibility?:~

~The code in this PR may be part of a blue-green deploy. Can upgrades from previous versions safely coexist? (Consider restarts of blue or green nodes.):

~Does this PR rely on statements being true about other products at a deployment - if so, do we have correct product dependencies on these products (or other ways of verifying that these statements are true)?:~

~Does this PR need a schema migration?~

Testing and Correctness

~What, if any, assumptions are made about the current state of the world? If they change over time, how will we find out?:~

What was existing testing like? What have you done to improve it?: pending

~If this PR contains complex concurrent or asynchronous code, is it correct? The onus is on the PR writer to demonstrate this.:~

~If this PR involves acquiring locks or other shared resources, how do we ensure that these are always released?:~

Execution

How would I tell this PR works in production? (Metrics, logs, etc.): When we wire this through, we will be adding metrics around transactions4

~Has the safety of all log arguments been decided correctly?:~

~Will this change significantly affect our spending on metrics or logs?:~

How would I tell that this PR does not work in production? (monitors, etc.): After wiring this in, transactions will start to fail if this component does not work.

~If this PR does not work as expected, how do I fix that state? Would rollback be straightforward?:~

~If the above plan is more complex than “recall and rollback”, please tag the support PoC here (if it is the end of the week, tag both the current and next PoC):~

Scale

~Would this PR be expected to pose a risk at scale? Think of the shopping product at our largest stack.:~

Would this PR be expected to perform a large number of database calls, and/or expensive database calls (e.g., row range scans, concurrent CAS)?: This component is expected to add an additional call to Cassandra for each transaction. We are hoping that batching + MCAS will be good enough to avoid any significant performance regression.

~Would this PR ever, with time and scale, become the wrong thing to do - and if so, how would we know that we need to do something differently?:~

Development Process

Where should we start reviewing?: TransactionService

~If this PR is in excess of 500 lines excluding versions lock-files, why does it not make sense to split it?:~

Please tag any other people who should be aware of this PR: @jeremyk-91 @sverma30 @raiju

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Type See change types. Select one:

• [ ] Feature
• [x] Improvement
• [ ] Fix
• [ ] Break
• [ ] Deprecation
• [ ] Manual task
• [ ] Migration

Description TTS | Introduce markInProgress endpoint in TransactionService for transaction schema version 4.

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