fix(core): re-subscribes to shared pair listener opens a new connection

[bjoerge]

Description

While testing #8110 I noticed that even when preloading, clicking a document would cause a new listener request to be made.

Tracked this down to being caused by the memoization of the shared document pair listener. This PR fixes the issue by:

• Replacing the connector.complete() trick with instead exposing a _keepalive stream that we merge in with the (memoized & shared) stream of the pair listener. This ensures that the listener connection will be kept open for as long as there are subscribers to the pair object.
• Moving the delayed reset to the memoized function (returning a pair listener for keyed by document id). This ensures that the delayed reset happens on the memoized observable itself, rather than the connection stream.

What to review

• Navigate to a document (A) in the Studio
• Make sure there is a single event source set up with the tag sanity.studio.document.pair-listener
• Navigate to another document (B)
• Make sure there is a single new event source set up with the tag sanity.studio.document.pair-listener
• Go back to document A before 10s has passed
• Verify that no request was made with the tag sanity.studio.document.pair-listener
• Stay on document A for more than 10s
• Verify that the listener connection made for document B is now shut down (timing panel no longer says "Caution: request is not finished yet!")
• Now, going back to B should trigger a new listener connection again.

Testing

Existing tests should be enough

Notes for release

n/a

[vercel]

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[github-actions]

No changes to documentation

[github-actions]

Component Testing Report Updated Dec 20, 2024 1:34 PM (UTC)

❌ Failed Tests (2) -- expand for details

File	Status	Duration	Passed	Skipped	Failed
comments/CommentInput.spec.tsx	✅ Passed (Inspect)	1m 3s	15	0	0
formBuilder/ArrayInput.spec.tsx	✅ Passed (Inspect)	12s	3	0	0
formBuilder/inputs/PortableText/Annotations.spec.tsx	✅ Passed (Inspect)	37s	6	0	0
formBuilder/inputs/PortableText/copyPaste/CopyPaste.spec.tsx	✅ Passed (Inspect)	50s	11	7	0
formBuilder/inputs/PortableText/copyPaste/CopyPasteFields.spec.tsx	✅ Passed (Inspect)	0s	0	12	0
formBuilder/inputs/PortableText/Decorators.spec.tsx	✅ Passed (Inspect)	25s	6	0	0
formBuilder/inputs/PortableText/DisableFocusAndUnset.spec.tsx	✅ Passed (Inspect)	14s	3	0	0
formBuilder/inputs/PortableText/DragAndDrop.spec.tsx	✅ Passed (Inspect)	26s	6	0	0
formBuilder/inputs/PortableText/FocusTracking.spec.tsx	✅ Passed (Inspect)	1m 6s	15	0	0
formBuilder/inputs/PortableText/Input.spec.tsx	✅ Passed (Inspect)	1m 29s	21	0	0
formBuilder/inputs/PortableText/ObjectBlock.spec.tsx	✅ Passed (Inspect)	1m 41s	18	0	0
formBuilder/inputs/PortableText/PresenceCursors.spec.tsx	✅ Passed (Inspect)	13s	3	9	0
formBuilder/inputs/PortableText/Styles.spec.tsx	✅ Passed (Inspect)	26s	6	0	0
formBuilder/inputs/PortableText/Toolbar.spec.tsx	❌ Failed (Inspect)	3m 4s	19	0	2
formBuilder/tree-editing/TreeEditing.spec.tsx	✅ Passed (Inspect)	0s	0	3	0
formBuilder/tree-editing/TreeEditingNestedObjects.spec.tsx	✅ Passed (Inspect)	0s	0	3	0

[github-actions]

⚡️ Editor Performance Report

Updated Fri, 20 Dec 2024 13:35:22 GMT

Benchmark	reference latency of sanity@latest	experiment latency of this branch	Δ (%) latency difference
article (title)	25.6 efps (39ms)	25.3 efps (40ms)	+1ms (+1.3%)	✅
article (body)	67.6 efps (15ms)	72.5 efps (14ms)	-1ms (-/-%)	✅
article (string inside object)	26.3 efps (38ms)	28.6 efps (35ms)	-3ms (-7.9%)	✅
article (string inside array)	25.3 efps (40ms)	25.0 efps (40ms)	+1ms (+1.3%)	✅
recipe (name)	52.6 efps (19ms)	57.1 efps (18ms)	-2ms (-7.9%)	✅
recipe (description)	58.8 efps (17ms)	62.5 efps (16ms)	-1ms (-5.9%)	✅
recipe (instructions)	99.9+ efps (5ms)	99.9+ efps (5ms)	+0ms (-/-%)	✅
synthetic (title)	19.8 efps (51ms)	20.8 efps (48ms)	-3ms (-5.0%)	✅
synthetic (string inside object)	21.3 efps (47ms)	21.3 efps (47ms)	+0ms (-/-%)	✅

efps — editor "frames per second". The number of updates assumed to be possible within a second.

Derived from input latency. efps = 1000 / input_latency

Detailed information

🏠 Reference result

The performance result of sanity@latest

Benchmark	latency	p75	p90	p99	blocking time	test duration
article (title)	39ms	46ms	58ms	434ms	676ms	9.8s
article (body)	15ms	18ms	23ms	180ms	209ms	5.0s
article (string inside object)	38ms	41ms	50ms	237ms	256ms	6.8s
article (string inside array)	40ms	42ms	47ms	175ms	162ms	6.7s
recipe (name)	19ms	22ms	27ms	48ms	0ms	7.2s
recipe (description)	17ms	20ms	26ms	33ms	0ms	4.5s
recipe (instructions)	5ms	7ms	10ms	25ms	0ms	3.0s
synthetic (title)	51ms	56ms	59ms	264ms	422ms	12.8s
synthetic (string inside object)	47ms	51ms	57ms	307ms	539ms	8.3s

🧪 Experiment result

The performance result of this branch

Benchmark	latency	p75	p90	p99	blocking time	test duration
article (title)	40ms	48ms	86ms	399ms	309ms	10.5s
article (body)	14ms	16ms	22ms	92ms	337ms	5.2s
article (string inside object)	35ms	38ms	44ms	144ms	147ms	6.5s
article (string inside array)	40ms	44ms	50ms	226ms	246ms	6.9s
recipe (name)	18ms	19ms	21ms	34ms	0ms	7.2s
recipe (description)	16ms	17ms	18ms	35ms	0ms	4.3s
recipe (instructions)	5ms	7ms	8ms	16ms	0ms	3.1s
synthetic (title)	48ms	49ms	66ms	128ms	515ms	12.4s
synthetic (string inside object)	47ms	50ms	60ms	424ms	748ms	7.9s

📚 Glossary

column definitions

• benchmark — the name of the test, e.g. "article", followed by the label of the field being measured, e.g. "(title)".
• latency — the time between when a key was pressed and when it was rendered. derived from a set of samples. the median (p50) is shown to show the most common latency.
• p75 — the 75th percentile of the input latency in the test run. 75% of the sampled inputs in this benchmark were processed faster than this value. this provides insight into the upper range of typical performance.
• p90 — the 90th percentile of the input latency in the test run. 90% of the sampled inputs were faster than this. this metric helps identify slower interactions that occurred less frequently during the benchmark.
• p99 — the 99th percentile of the input latency in the test run. only 1% of sampled inputs were slower than this. this represents the worst-case scenarios encountered during the benchmark, useful for identifying potential performance outliers.
• blocking time — the total time during which the main thread was blocked, preventing user input and UI updates. this metric helps identify performance bottlenecks that may cause the interface to feel unresponsive.
• test duration — how long the test run took to complete.

[stipsan]

Such a great find!!! 💖