react-doctor/no-fetch-in-effect
Use `useQuery()` from @tanstack/react-query, `useSWR()`, or fetch in a Server Component instead
- Status
- Active
- Category
- State & Effects
- Assessment
- Evidence-required risk
- Required evidence
- source code
- Default configuration
- Enabled
- Default severity
- warn
Show technical metadata
- Scope
- All supported frameworks
- Active when
- always
- Requirements
- react
- Priority
- 54 (P2)
- Source
- oxlint-plugin-react-doctor
- Rule set
- oxlint-plugin-react-doctor 0.9.3 (prompt schema 2)
Validation prompt
Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.
Fires when a useEffect callback contains anywhere a CallExpression whose callee is in FETCH_CALLEE_NAMES (fetch, ky, got, wretch, ofetch) or whose object identifier is in FETCH_MEMBER_OBJECTS (axios.get, ky.post, got.json, request.delete: any method on those receivers). The walker descends into nested functions, so await fetch(...) inside an async IIFE or a .then() callback still triggers.
Suppress when: a one-shot fetch with proper AbortController cleanup in a small project that has not adopted a data-fetching library.
Evidence boundary
The diagnostic proves only that the detector’s modeled source pattern matched. It does not prove runtime impact, product intent, rendered failure, or that one remediation is correct.
Establish the environment, repository policy, exceptions, and required rendered or runtime evidence before deciding the occurrence.
Record one outcome:
- Confirmed failure: The required evidence establishes the violation.
- Rejected: A documented exception or false-positive predicate applies.
- Needs evidence: Named evidence can still be collected.
- Unavailable: Required evidence cannot be collected in this run.
- Waived with evidence: An authorized, scoped exception applies to an established failure.
- Observation: The review records an optional tradeoff without claiming a defect.
A waiver records its scope, authority, evidence, and review condition. It is not a pass or false positive.
Default severity is registry metadata. Use the occurrence’s JSON severity after repository configuration when ordering real findings.
Fix prompt
Apply this candidate correction only after the required evidence confirms the risk.
Replace the effect with useQuery from @tanstack/react-query or useSWR: both handle caching, request deduplication, race conditions, retries, and refetch-on-focus for you. In Next.js App Router and other RSC frameworks, move the fetch into a Server Component or Route Handler so it never ships to the client. See https://react.dev/reference/react/useEffect#fetching-data-with-effects
Repository-wide copy prompt
Use this repository-wide prompt only after validating each occurrence. For one occurrence, use the guidance above.
Show repository-wide prompt
Fix every confirmed react-doctor/no-fetch-in-effect diagnostic in the current repository.
Required change:
- Replace the effect with useQuery from @tanstack/react-query or useSWR: both handle caching, request deduplication, race conditions, retries, and refetch-on-focus for you. In Next.js App Router and other RSC frameworks, move the fetch into a Server Component or Route Handler so it never ships to the client. See https://react.dev/reference/react/useEffect#fetching-data-with-effects.
Validation before editing:
Fires when a useEffect callback contains anywhere a CallExpression whose callee is in FETCH_CALLEE_NAMES (fetch, ky, got, wretch, ofetch) or whose object identifier is in FETCH_MEMBER_OBJECTS (axios.get, ky.post, got.json, request.delete: any method on those receivers). The walker descends into nested functions, so await fetch(...) inside an async IIFE or a .then() callback still triggers.
Suppress when: a one-shot fetch with proper AbortController cleanup in a small project that has not adopted a data-fetching library.
Constraints:
- Make the smallest change that fixes the root cause.
- Preserve behavior and interfaces unrelated to this diagnostic.
- Reuse existing project components, utilities, and conventions.
- Do not introduce render-phase side effects, render-phase state updates, or Hooks rule violations.
- Adapt identifiers and framework details instead of copying blindly.
- Do not disable the rule or suppress matching code.
Assessment:
- Record detector evidence, applicability facts, assumptions, missing evidence, and the rule class for this occurrence.
- Return one outcome: Confirmed failure, Rejected, Needs evidence, Unavailable, Waived with evidence, or Observation.
- A waiver records the established failure, scope, authority, evidence, and review or expiry condition. It is not a pass or false positive.
Verification:
- Run focused tests for the changed behavior.
- Run React Doctor and confirm this diagnostic no longer appears from changed code.
- Run an unfiltered scan of the affected scope before claiming no cross-category regression.
- Report the files changed and any checks you could not run.