Deno 2.1.5 regressions with DNS regarding axios (due to node compat change)

[hourianto]

Noticed that some of my scripts started failing after I upgraded to 2.1.5.

This replicates part of the issue:

import axios from "npm:axios"

async function makeRequest(): Promise<void> {
  try {
    await axios.get("https://test.openai.azure.com")
  } catch (error) {
    console.error(new Date().toISOString(), axios.isAxiosError(error) ? error.message : error)
  }
}

async function main(): Promise<void> {
  const batchSize = 5

  while (true) {
    await Promise.all(Array(batchSize).fill(null).map(() => makeRequest()))
    await new Promise((resolve) => setTimeout(resolve, 1000))
  }
}

main().catch((error) => console.error("Error:", error))

With this script I'm getting random logs like:

dropped malformed message waiting for id: 45650 err: unexpected end of input reached
dropped malformed message waiting for id: 26004 err: unexpected end of input reached
dropped malformed message waiting for id: 35252 err: unexpected end of input reached
dropped malformed message waiting for id: 33116 err: unexpected end of input reached
dropped malformed message waiting for id: 25559 err: unexpected end of input reached
dropped malformed message waiting for id: 36211 err: unexpected end of input reached
dropped malformed message waiting for id: 28699 err: unexpected end of input reached

In my real script (sadly I cannot publish that code) I also get those random errors. In short, the real code does lots of requests each second to different domains some of which don't exist anymore, but most do:

dropped malformed message waiting for id: 54215 err: rdata length too large for remaining bytes, need: 4 remain: 3
dropped malformed message waiting for id: 34012 err: rdata length too large for remaining bytes, need: 4 remain: 1
dropped malformed message waiting for id: 31268 err: rdata length too large for remaining bytes, need: 4 remain: 1
dropped malformed message waiting for id: 62347 err: unexpected end of input reached
dropped malformed message waiting for id: 42106 err: unexpected end of input reached
dropped malformed message waiting for id: 62387 err: unexpected end of input reached

Second case (I discovered this by accident):

import axios from "npm:axios"

async function main(): Promise<void> {
  try {
    const response = await axios.get("https://doesntexist213659tetee.com")
  } catch (error) {
    if (axios.isAxiosError(error)) {
      console.error(`Failed with error: ${error.message}`)
    } else {
      console.error(`Unexpected error: ${error}`)
    }
  }
}

await main()
console.log("caught it")

With Deno 2.1.4 and below this runs properly and outputs "caught it" (since it catches the error), with 2.1.5 I get a hard crash (that does not get caught by the catch):

error: Uncaught Error: getaddrinfo ENOTFOUND doesntexist213659tetee.com
    at __node_internal_captureLargerStackTrace (ext:deno_node/internal/errors.ts:93:9)
    at __node_internal_ (ext:deno_node/internal/errors.ts:246:10)
    at GetAddrInfoReqWrap.onlookupall [as oncomplete] (node:dns:43:26)
    at ext:deno_node/internal_binding/cares_wrap.ts:71:9
    at eventLoopTick (ext:core/01_core.js:175:7)

With native fetch everything works fine.

#27642 might have the same root cause

[kt3k]

dropped malformed message waiting for id: 45650 err: unexpected end of input reached
dropped malformed message waiting for id: 26004 err: unexpected end of input reached
dropped malformed message waiting for id: 35252 err: unexpected end of input reached
dropped malformed message waiting for id: 33116 err: unexpected end of input reached

Do you see these error messages with exactly the above example, or do you modify the URL part?

If I ran the first example, I saw the errors like:

$ deno -A a.ts
2025-01-15T07:57:35.165Z Request failed with status code 404
2025-01-15T07:57:35.169Z Request failed with status code 404
2025-01-15T07:57:35.169Z Request failed with status code 404
2025-01-15T07:57:35.169Z Request failed with status code 404
2025-01-15T07:57:35.169Z Request failed with status code 404
2025-01-15T07:57:36.542Z Request failed with status code 404
2025-01-15T07:57:36.544Z Request failed with status code 404

which is the same as what Node.js shows.

Second case (I discovered this by accident):

This case seems a regression in 2.1.5. I'll work on it.

---

Note: We changed the internal implementation of Node compat http(s).request in 2.1.5 (#25470). In the new implementation we started using dns.lookup for resolving domain names, and this is probably related to it.

I guess probably our dns resolver (It internally uses Deno.resolveDns which internally uses hickory-dns) is now too strict about handling dns data.

The error message is likely from here https://github.com/hickory-dns/hickory-dns/blob/b942d68020ee6f88bbd459812c5fab22b748413c/crates/proto/src/udp/udp_client_stream.rs#L318

[hourianto]

@kt3k for the first case - yeah, I see errors in the console with that exact code. It takes some time to get them though, a few seconds perhaps. This is what dig returns for that domain:

test.openai.azure.com.  900     IN      CNAME   koreacentral.api.cognitive.microsoft.com.
koreacentral.api.cognitive.microsoft.com. 3600 IN CNAME cognitivekcprod.trafficmanager.net.
cognitivekcprod.trafficmanager.net. 30 IN CNAME cognitivekcprod.azure-api.net.
cognitivekcprod.azure-api.net. 900 IN   CNAME   apimgmttm6jlrkljhsnxfyj4ybmjxuinaoxgxjlz8tpdomzoya.trafficmanager.net.
apimgmttm6jlrkljhsnxfyj4ybmjxuinaoxgxjlz8tpdomzoya.trafficmanager.net. 300 IN CNAME cognitivekcprod-koreacentral-01.regional.azure-api.net.
cognitivekcprod-koreacentral-01.regional.azure-api.net. 900 IN CNAME apie98ecb42422c43a49d717dbbb805352ekhsube4o75jbgtwcyzkxp.koreacentral.cloudapp.azure.com.
apie98ecb42422c43a49d717dbbb805352ekhsube4o75jbgtwcyzkxp.koreacentral.cloudapp.azure.com. 10 IN A 20.194.72.197

[kt3k]

Do you see the same error (dropped malformed message waiting for id: 45650 err: unexpected end of input reached) when executing the below script?

console.log(await Deno.resolveDns("test.openai.azure.com.", "A"));

[hourianto]

Hmm, no, if I do this (even in a loop or multiple concurrent ones), it's all fine. Is there a way I can understand why I'm getting all those console errors? I could build Deno if needed

[kt3k]

Sounds very strange situation to me..

axios uses node:https.request which uses node:dns.lookup which uses Deno.resolveDns. So can you also check if the issue reproduces with the below scripts? (This should narrow where the issue exists)

import dns from "node:dns"
dns.lookup("test.openai.azure.com", console.log);

import https from "node:https"
https.request("https://test.openai.azure.com", console.log).end()

[hourianto]

Yeah, I get the error with the first snippet, but it's inconsistent. Sometimes it just gives the IP straight away, sometimes it does this:

dropped malformed message waiting for id: 62340 err: unexpected end of input reached
dropped malformed message waiting for id: 24232 err: unexpected end of input reached
null 20.194.72.197 4