[Due for payment 2026-01-28] [Due for payment 2026-01-23] [Due for payment 2026-01-20] [$250] Restore Type Safety for Onyx.update()

[blazejkustra]

Background:

The frontend frequently reads and writes data to the backend using the Onyx data layer. Whenever a request is made, we optimistically set Onyx data via Onyx.update(). First updating the local cache, then syncing changes once the request succeeds/fails.

During the migration to TypeScript, @fabioh8010 and I ensured this function and accompanying types were type-safe, meaning only values defined in the Onyx schema could be set under a specific key. This safeguard protected against corrupted data, unexpected keys, and typos in key names, improving developer experience and data reliability.

Problem:

It's possible to set any value to any key when using Onyx.update():

    const optimisticData: OnyxUpdate[] = [
        {
            onyxMethod: Onyx.METHOD.MERGE,
            key: ONYXKEYS.IS_LOADING_REPORT_DATA, // boolean
            value: 'whatever value', // this doesn't raise a type error
        },
    ];

Solution:

Reintroduce the previous type definition in react-native-onyx (as it was implemented before PR #600) to restore schema-based type enforcement.

Then:
Update react-native-onyx in E/App.
Resolve around 120 resulting type errors in E/App

This change will restore strict type safety for Onyx.update(), preventing invalid data assignments at compile-time.

In React-native-onyx this will also be included:

• add a comment above this magic type so that nobody touches it again
• add type tests to Onyx

Upwork Automation - Do Not Edit

• Upwork Job URL: https://www.upwork.com/jobs/~021983883548495225073
• Upwork Job ID: 1983883548495225073
• Last Price Increase: 2025-10-30
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• abzokhattab | Contributor | 109423537

Issue Owner

Current Issue Owner: @heyjennahay

[melvin-bot]

Job added to Upwork: https://www.upwork.com/jobs/~021983883548495225073

[melvin-bot]

Triggered auto assignment to Contributor-plus team member for initial proposal review - @Ollyws (External)

[melvin-bot]

Triggered auto assignment to @heyjennahay (Bug), see https://stackoverflow.com/c/expensify/questions/14418 for more details. Please add this bug to a GH project, as outlined in the SO.

[blazejkustra]

@Ollyws I'll post a PR tomorrow morning as I couldn't get type tests to work properly