incremental delivery with deduplication + concurrent execution

At a glance

• Identifier: #1034
• Stage: RFCX: Closed 2023-11-07T10:07:26Z
• Champion: @yaacovCR
• PR: incremental delivery with deduplication + concurrent execution

Timeline

• Commit pushed: use identifiers instead of records when possible on 2023-09-28 by @yaacovCR
• Commit pushed: scattered fixes, streamlining on 2023-09-26 by @yaacovCR
• Spec PR created on 2023-07-12 by yaacovCR
• Commit pushed: incremental delivery with deduplication, concurrent delivery, and ear… on 2023-05-21 by @yaacovCR
• Commit pushed: CollectFields does not require path or asyncRecord (#11) on 2023-01-16 by @yaacovCR
• Commit pushed: replace server with service on 2023-01-15 by @robrichard
• Commit pushed: fix typo on 2022-12-05 by @robrichard
• Commit pushed: fix parentRecord argument in ExecuteStreamField (#7) on 2022-11-29 by @yaacovCR
• Commit pushed: clarify label is not required on 2022-11-23 by @robrichard
• 2 commits pushed on 2022-11-22:
  • Raise a field error if defer/stream encountered during subscription e… by @robrichard
  • Add validation rule for defer/stream on subscriptions by @robrichard
• Commit pushed: Add error handling for stream iterators (#5) on 2022-11-21 by @yaacovCR
• Commit pushed: fix typos (#6) on 2022-11-18 by @yaacovCR
• Commit pushed: remove ResolveFIeldGenerator (#4) on 2022-11-16 by @yaacovCR
• Commit pushed: small fixes (#3) on 2022-11-07 by @yaacovCR
• Commit pushed: update on hasNext on 2022-11-01 by @robrichard
• Commit pushed: link to note on should on 2022-10-12 by @robrichard
• 3 commits pushed on 2022-09-09:
  • typo by @robrichard
  • improve non-null example by @robrichard
  • Add FilterSubsequentPayloads algorithm by @robrichard
• 11 commits pushed on 2022-09-08:
  • Add error boundary behavior by @robrichard
  • defer/stream response => payload by @robrichard
  • event stream => response stream by @robrichard
  • link to path section by @robrichard
  • use case no dash by @robrichard
  • remove "or null" by @robrichard
  • add detailed incremental example by @robrichard
  • update label validation rule by @robrichard
  • clarify hasNext on incremental example by @robrichard
  • clarify canceling of subsequent payloads by @robrichard
  • Add examples for non-null cases by @robrichard
• Commit pushed: clarify null behavior of if on 2022-08-24 by @robrichard
• 2 commits pushed on 2022-08-23:
  • if: Boolean! = true by @robrichard
  • address pr feedback by @robrichard
• 7 commits pushed on 2022-08-18:
  • Introduce @defer and @stream. by @robrichard
  • Raise a field error if initialCount is less than zero by @robrichard
  • wait for parent async record to ensure correct order of payloads by @robrichard
  • spec updates to reflect latest discussions by @robrichard
  • Note about mutation execution order by @robrichard
  • minor change for uniqueness by @robrichard
  • fix typos by @robrichard
• Commit pushed: Align deferred fragment field collection with reference implementation on 2022-08-03 by @robrichard
• 3 commits pushed on 2022-06-09:
  • add missing line by @robrichard
  • fix ExecuteRequest by @robrichard
  • fix response by @robrichard
• 2 commits pushed on 2022-03-23:
  • fix wrong quotes by @robrichard
  • remove label/path requirement by @robrichard
• Commit pushed: Clarification on labels on 2022-03-08 by @robrichard
• Commit pushed: add validation “Defer And Stream Directive Labels Are Unique” on 2022-03-07 by @robrichard
• 2 commits pushed on 2022-02-07:
  • stream if argument, indexPath -> itemPath by @robrichard
  • Clarify stream only applies to outermost list of multi-dimensional ar… by @robrichard
• Commit pushed: deferDirective and visitedFragments on 2022-02-02 by @robrichard
• Commit pushed: fix typo on 2022-01-21 by @robrichard
• Commit pushed: add isCompletedIterator to AsyncPayloadRecord to track completed iter… on 2021-12-30 by @robrichard
• 2 commits pushed on 2021-12-20:
  • Simplify execution, payloads should begin execution immediately by @robrichard
  • Clarify error handling by @robrichard
• 2 commits pushed on 2021-12-06:
  • data is not necessarily an object in subsequent payloads by @robrichard
  • add Defer And Stream Directives Are Used On Valid Root Field rule by @robrichard
• Commit pushed: fix typo on 2021-11-26 by @robrichard
• Commit pushed: allow extensions only subsequent payloads on 2021-11-25 by @robrichard
• Commit pushed: clarify negative values of initialCount on 2021-11-20 by @robrichard
• Commit pushed: clarification on defer/stream requirement on 2021-11-19 by @robrichard
• Commit pushed: Update Section 3 -- Type System.md on 2021-05-15 by @robrichard
• 3 commits pushed on 2021-02-17:
  • fix typos by @robrichard
  • clear up that it is legal to support either defer or stream individually by @robrichard
  • Add sumary of arguments to Type System by @robrichard

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supersedes #1026

This version sets up an Incremental Publisher Record that includes: (a) an Execution Event Queue input stream on the and (b) a Subsequent Result output stream.

No mutations happen outside the algorithms that define any records.

With the following caveats:

1. The event queue is not considered to be "mutated" when different sub-algorithms push events into it.
2. The CreateIncrementalPublisher() algorithm is where the magic happens, a long algorithm where the Execution Event Handler and lazily executed Subsequent Result stream are managed concurrently. To increase readability, several subprocedures/macros/inner functions are defined that have access to the variables defined within the entire algorithm.