Eric Allam
02cf9c81ad
## Summary A Query page (TRQL) query that pulls fields out of a run's `output` with JSON functions (`JSONExtractString`, `JSONExtractInt`, `JSONHas`, and the rest of the family) failed with "The first argument of function ... should be a string containing JSON, illegal type: JSON". Those queries now work. ## Root cause and fix `output` is a native ClickHouse `JSON` column, but `JSONExtract*`, `JSONHas`, `JSONLength`, and `JSONType` all expect a String containing JSON text. The compiler already swaps in the column's String companion (`output_text`) when a JSON column is selected or compared, but not inside function-call arguments, so it emitted `JSONExtractInt(output, 'x')` against the native column. The fix prints the companion column for the first argument of these functions when it resolves to a bare JSON field, keeping the table alias when qualified (so it works in JOINs): JSONExtractInt(output, 'x') -> JSONExtractInt(output_text, 'x') JSONExtractArrayRaw(assumeNotNull(output), 'y') -> JSONExtractArrayRaw(assumeNotNull(output_text), 'y') It also reaches through value-preserving passthrough wrappers like `assumeNotNull(...)`, while leaving value-changing wrappers like `toJSONString(output)` on the native column (that argument is already a String). The swap is also semantically correct, not just a type fix: `output_text` is the unwrapped data JSON that the TRQL `output` model already represents, so field paths line up. Covered by printer unit tests and a ClickHouse integration test that runs the whole family (plus the wrapped and `toJSONString` cases) against a real native-JSON column. Both new cases fail with the exact "illegal type: JSON" error without the fix.
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About Trigger.dev
Trigger.dev is the open-source platform for building AI workflows in TypeScript. Long-running tasks with retries, queues, observability, and elastic scaling.
The platform designed for building AI agents
Build AI agents using all the frameworks, services and LLMs you're used to, deploy them to Trigger.dev and get durable, long-running tasks with retries, queues, observability, and elastic scaling out of the box.
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Long-running without timeouts: Execute your tasks with absolutely no timeouts, unlike AWS Lambda, Vercel, and other serverless platforms.
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True runtime freedom: Customize your deployed tasks with system packages – run browsers, Python scripts, FFmpeg and more.
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Observability & monitoring: Each run has full tracing and logs. Configure error alerts to catch bugs fast.
Key features:
- JavaScript and TypeScript SDK - Build background tasks using familiar programming models
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import { task } from "@trigger.dev/sdk";
//1. You need to export each task
export const helloWorld = task({
//2. Use a unique id for each task
id: "hello-world",
//3. The run function is the main function of the task
run: async (payload: { message: string }) => {
//4. You can write code that runs for a long time here, there are no timeouts
console.log(payload.message);
},
});
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