Get error fetch failed when i make a post request on localhost but wouldn't expect it

MarkusHobisch — Thu, 20 Apr 2023 07:49:07 GMT

Problem:

I have a node.js server running on localhost on port 3000. When I do a POST request in an app function I get an error. If I do the same request to remote url it works fine.

Error I got:

console.error response failed because: TypeError: fetch failed at fetch (C:\Users\markus.hobisch\IdeaProjects\dynatrace-cpa\node_modules\undici\index.js:105:13) at processTicksAndRejections (node:internal/process/task_queues:95:5) at makePostRequest (C:\Users\markus.hobisch\IdeaProjects\dynatrace-cpa\api\collect-cloudwatch-logs-vpc-logs.ts:19:20) at fetchData (C:\Users\markus.hobisch\IdeaProjects\dynatrace-cpa\api\collect-cloudwatch-logs-vpc-logs.ts:67:16) at collectCloudwatchLogsVpcLogs (C:\Users\markus.hobisch\IdeaProjects\dynatrace-cpa\api\collect-cloudwatch-logs-vpc-logs.ts:89:22) at Object.<anonymous> (C:\Users\markus.hobisch\IdeaProjects\dynatrace-cpa\api\fetch-cloud-watch-logs.test.ts:34:54) { cause: Error: connect ECONNREFUSED ::1:3000 at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1487:16) at TCPConnectWrap.callbackTrampoline (node:internal/async_hooks:130:17) { errno: -4078, code: 'ECONNREFUSED', syscall: 'connect', address: '::1', port: 3000 } }

I added a screenshot with the error I got in debug UI as well.

I just made a simple post request to localhost and remote host. To produce the error you can use the code below:

Cheers

Markus

Re: Get error fetch failed when i make a post request on localhost but wouldn't expect it

christian_barth — Wed, 19 Apr 2023 07:39:14 GMT

Hi Markus,

I assume want to call your local API from your locally running App, right?

As soon as your app function is deployed, you can't reach localhost.

The error you're getting is a generic "Connection refused" from node.

On which port you are running your app dev server?

Re: Get error fetch failed when i make a post request on localhost but wouldn't expect it

MarkusHobisch — Mon, 20 Feb 2023 17:37:37 GMT

Hi Christian,

I think I already solved my problem. The problem was that I used localhost instead of 127.0.0.1. This is a known bug in NodeJS 18. See here: ECONNREFUSED on NodeJS 18 · Issue #1624 · node-fetch/node-fetch · GitHub.
After I changed this my tests are green now. Thank you anyway for your response.

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Get error fetch failed when i make a post request on localhost but wouldn't expect it

Re: Get error fetch failed when i make a post request on localhost but wouldn't expect it

Re: Get error fetch failed when i make a post request on localhost but wouldn't expect it