implement correct merging of incremental respones (@defer/@stream)

[thomasheyenbrock]

Hello fellow GraphiQL friends 👋

We recently stumbled over the fact that GraphiQL does not yet implement the latest incremental response format for defer/stream, concretely the incremental payload property is not handled.

This PR cleans up the merge logic and makes it work for any incremental response payload. (Big inspiration taken from graphql-tools/utils, but if felt overkill to add the whole package just for this one utility, and since this is the official reference implementation for a GraphQL IDE it felt appropriate to have that utility as first-class citizen in our code.)

Some before-after illustrations:

Feature	Before	After
Defer
Stream

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🦋 Changeset detected

Latest commit: 8acbecf

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 4 packages

Name	Type
@graphiql/react	Minor
@graphiql/plugin-code-exporter	Major
@graphiql/plugin-explorer	Major
graphiql	Patch

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[yaacovCR]

Neat!

Something I've been wondering...

The new response format has each payload containing supplemental data/items, but also metadata about the incremental stream in the form of pending/completed notifications.

With the UI strategy of merging incremental data into the initial response, that information is not currently shown. It also makes it impossible to tell from the final result what actually happened; the user has to watch carefully as the process unfolds.

Might we want to model display of incremental results similar to subscriptions in which we just display the different payloads separately.

Maybe as a toggle-able separate useful option?

[thomasheyenbrock]

I've been pondering about that as well. GraphiQL currently has no good interface for long-running requests that return more than one payload.

• For subscriptions you only ever see the latest payload (GraphiQL does replace the result contents each time a payload is received)
• For defer/stream you only see the latest combined result, but not the increments (like you mentioned @yaacovCR)

This would need some bigger re-architecting for how the internal state is managed as well as the UI. I see that as outside of the scope of this PR which is just intending to fix the most pressing issues with defer/stream.

[yaacovCR]

Oh => I suppose I am simply mistaken about subscriptions. Sorry about that!

[acao]

yes this UI change to results for subscriptions has been something we've been hoping to execute for a while. And incremental delivery with stream creates another UI case, where we want to see the final result but also a log of the requests that formed that result. We hope to expose plugins for custom tabs in results, and to allow overriding the results pane, and the other idea we had years ago was for these results plugins could register and display for specific response types automatically.

[acao]

@thomasheyenbrock looks awesome! just need to fix this ts bug:

src/execution.tsx(364,7): error TS2357: The operand of an increment or decrement operator must be a variable or a property access.

and get the unit and related cypress tests passing. if you like, i can show you how to enable to e2e tests for defer and stream, if this has been merged into graphql by now? previously, the e2e tests for defer and stream were designed to be run against the special release tag version for years, so it's just a small tweak to cypress to get them to run for the stable graphql release version

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 17 lines in your changes are missing coverage. Please review.

Project coverage is 55.31%. Comparing base (29e99a8) to head (8acbecf).
Report is 2 commits behind head on main.

Additional details and impacted files

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##             main    #3580      +/-   ##
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- Coverage   55.33%   55.31%   -0.03%     
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  Files         115      115              
  Lines        5349     5351       +2     
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==========================================
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- Misses       1963     1965       +2     
  Partials      426      426              

Files	Coverage Δ
packages/graphiql-react/src/execution.tsx	13.15% <0.00%> (-0.24%)	⬇️

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[thomasheyenbrock]

Fixed the TS and linter issues 👍 (sorry for taking so long to come back to this). Will have another look at e2e tests tomorrow. The current ones are passing but I also remember that we had some for defer/stream, so worth a look.

[acao]

@thomasheyenbrock awesome! yes the e2e tags are designed to reference the graphql tag in package.json, and were previously run in the graphql version test matrix which i think we disabled. if defer and stream are in the stable graphql release we can get rid of that logic

[thomasheyenbrock]

Yes, just found the same thing 👍 will merge this for now and look into testing defer/stream reliably a bit more in detail separately