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Timeout for Deno

Create (abortable) promises that reject when the delay is exceeded.

Very useful for racing strategies using Promise.race or Abort.race.

Install

$ deno cache https://deno.land/x/timeout/mod.ts

Usage with await

import { Timeout, TimeoutError } from "https://deno.land/x/timeout/mod.ts"

const timeout = Timeout.promise(1000)

try {
    timeout.abort()
    await timeout
} catch(e){
    if(e instanceof TimeoutError)
        // Timed out
    if(e instanceof AbortSignal)
        // Aborted
}

Usage with callbacks

Since they reject when timed out, and reject when aborted, they never resolve.

import { Timeout, TimeoutError } from "https://deno.land/x/timeout/mod.ts"

Timeout.promise(1000)
    .catch((e) => console.error("Timed out or aborted"))
    .abort()

Usage with racing Promises

You can use Timeout.race to race some Promises with a timeout.

Promises are ignored if the delay is exceeded.

import { Timeout, TimeoutError } from "https://deno.land/x/timeout/mod.ts"

try{
    const req1 = fetch("...")
    const req2 = fetch("...")

    // Requests are ignored if the delay is exceeded
    const res = await Timeout.race([req1, req2], 1000)
    const json = await res.json()
} catch(e){
    if(e instanceof TimeoutError)
        // Timed out
}

Usage with racing Abortables

You can use Timeout.race to race some Abortables with a timeout.

Abortables are aborted if the delay is exceeded.

import { Abort, Abortable } from "https://deno.land/x/abortable/mod.ts"
import { Timeout, TimeoutError } from "https://deno.land/x/timeout/mod.ts"

try{
    const req = Abort.fetch("...")
    const req2 = Abort.fetch("...")

    // Both requests are aborted if the delay is exceeded
    const res = await Timeout.race([req1, req2], 1000)
    const json = await res.json()
} catch(e){
    if(e instanceof TimeoutError)
        // Timed out
}

Test

Run test.ts with the given timeout delay (in milliseconds)

$ deno run test.ts 1000
OK

$ deno run test.ts 100
Timeout