Problem

For http2 requests with defined sessionTimeout connection is not closed after the timeout and if there are no new requests, so it is wasted resources. Code to reproduce:

const axios = require('axios');

async function main() {
    const instance = axios.create( {
        maxRedirects: 0,
        httpVersion: 2,
        http2Options: {
            sessionTimeout: 5000,
            rejectUnauthorized: false,
        },
    });

    const response = await instance.request({ url: 'https://example.com/' });
    console.log(response.status, response.data.length);
}

main()
    .catch(console.error);

Without the fix, after the request and 5sec timeout application still running, because underlying connection is still open and Nodejs cannot quit (only server can close it).
With the fix the application is closed after 5sec.

Summary by cubic

Closes idle HTTP/2 sessions in removeSession() after sessionTimeout to prevent leaked connections. Frees resources and lets Node exit when idle.

Description

• Summary of changes
  • Call session.close() in Http2Sessions.removeSession() if the session isn’t already closed.
• Reasoning
  • Idle HTTP/2 sessions stayed open after timeout, keeping the process alive.
• Additional context
  • Affects HTTP/2 only when http2Options.sessionTimeout is set. No API changes.

Testing

• Added unit test in test/unit/adapters/http.js that makes an HTTP/2 request with sessionTimeout, listens for the 'close' event, waits past the timeout, and asserts the session closed.

^{Written for commit dbee25b. Summary will update on new commits.}