[http] fetch leaks responses that are never read (including every 204)

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
54/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
javascript, rust
Domain
backend, networking

Research direction

Start in the tauri-plugin-http fetch response handling and trace how ReqwestResponse resources are retained when a body is read, left unread, or has a null-body status. Use the linked reproduction to confirm the leak and compare its 204 and unread-body cases. Done means those cases release response resources and connections as native fetch does.

Written by the indexing model from the issue text.

Description

plugin: http type: bug
Describe the bug

tauri-plugin-http keeps every response on the Rust side until JS reads the whole body or cancels it. So these responses are never freed:

  • a response whose body is never read
  • every 204 (and other null-body status) response, even if you read it

With large bodies, each leaked response also keeps its TCP connection open. An app opened from the Dock can only open 256 files, so after about 250 such requests, every new request fails.

I'll have my AI agent post a more detailed analysis below.

Reproduction

https://github.com/ocavuebot/tauri-http-leak-repro

Minimal case:

for (let i = 0; i < 300; i++) {
  const res = await fetch('http://127.0.0.1:PORT/empty') // answers 204
  await res.arrayBuffer()
}

After the loop, the resource table still holds 300 ReqwestResponse entries, after GC and after location.reload(). The same loop with a 256 KB body and no read leaves 300 open sockets in the app process.

Expected behavior

Same as the webview's native fetch: nothing leaks. With native fetch, the same tests leave nothing behind.

Full tauri info output
[✔] Environment
    - OS: Mac OS 27.0.1 arm64 (X64)
    ✔ Xcode Command Line Tools: installed
    ✔ Xcode: 27.1
    ✔ rustc: 1.99.1 (58cf8f9c3 2026-10-13)
    ✔ cargo: 1.99.1 (5f94df478 2026-08-27)
    ✔ rustup: 1.29.1 (d95a37b6a 2026-08-13)
    ✔ Rust toolchain: stable-aarch64-apple-darwin (default)
    - node: 24.21.0
    - pnpm: 12.14.0
    - yarn: 1.22.22
    - npm: 11.19.0
[-] Packages
    - tauri 🦀: 2.12.4, (outdated, latest: 2.12.5)
    - tauri-build 🦀: 2.7.3, (outdated, latest: 2.7.4)
    - wry 🦀: 0.57.0, (outdated, latest: 0.57.1)
    - tao 🦀: 0.37.1, (outdated, latest: 0.37.2)
[-] Plugins
    - tauri-plugin-http 🦀: 2.8.3
    - tauri-plugin-fs 🦀: 2.7.1
[-] App
    - build-type: build
    - CSP: unset
    - frontendDist: ../dist
Stack trace
Additional context

No response

Dominant language
Rust
Stars
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Forks
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Avg merge
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Merged PRs (30d)
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