Amplify Rest API PUT Request is throwing message : unknown error

[saharJ95]

Before opening, please confirm:

• I have searched for duplicate or closed issues and discussions.
• I have read the guide for submitting bug reports.
• I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

JavaScript Framework

React

Amplify APIs

REST API

Amplify Version

v6

Amplify Categories

api

Backend

Other

Environment information

# Put output below this line

Describe the bug

I am using amplify RestAPi PUT request...
I am getting this Unkonwn Error

Expected behavior

I am not getting backend errors properly this is the response of API

Reproduction steps

Update any PUT request that's has an error

Code Snippet

I am using this code fir all REST API request but PUT is behaving odd in error cases

Log output

// Put your logs below this line

aws-exports.js

No response

Manual configuration

No response

Additional configuration

No response

Mobile Device

No response

Mobile Operating System

No response

Mobile Browser

No response

Mobile Browser Version

No response

Additional information and screenshots

No response

[chrisbonifacio]

Hi @saharJ95 can you provide some information about your API?

For example, is it restricted only to authenticated user or does it allow guest users?

Curious if IAM is being used to authorize requests.

Are you adding any additional configurations to the API library in your Amplify.configure call?

Would you be able to provide a code example of your PUT endpoint or reproduction steps so that we can try to reproduce the issue?

Lastly, what version of aws-amplify are you using?

[saharJ95]

Hi @chrisbonifacio ,
It is a restricted PUT request
This is how I am configuring my endPoints and auth

What I am doing is verifying validation Requests i.e. "400 Bad Request" and "500 Internal Error"

API Response is 400 with handled response

But in Catch of PUT Request, I am getting an Unknown Error

"aws-amplify": "^6.0.13",

[chrisbonifacio]

@saharJ95 thanks for the quick response!

Is this the only endpoint that is restricted the same way and failing with a 400 status code?

The status code suggests there's something invalid about the request itself like the body vs the authorization header. Can you confirm that the data in the payload is what you'd expect in the route handler logic? Do you see any errors in the Cloudwatch logs for the lambda that handles that route?

[saharJ95]

@chrisbonifacio Ok maybe I am not communicating my issue correctly.

I want to catch understandable API errors (400,401,500,404) in my catch block that is working fine with all other rest APIs method (GET, POST , DEL) .
In PUT case if API returns 404,500,401 (Handled Responses from my backend), the catch block of PUT request gives UNKNOWN ERROR...

It SHOULD return the same response that is API is returning..

[chrisbonifacio]

Hi @saharJ95

So, I'm able to reproduce the behavior you're describing but I'm not sure if I understand how you're getting the full error response payload to be logged to the console.
I only get UnknownError for each http request that I fail with a 400 status code.

Here are the steps I took to reproduce:

I created a REST API with express integration using the Amplify CLI.
I add some routes that respond with a 400 status code and a json body.

On the front end, I just have a few buttons to make a successful POST, a failed POST, and failed PUT requests.

This is what gets logged when I catch the error for either a POST or PUT request.

Here's the Express server code for my reproduction app:
https://github.com/chrisbonifacio/ampv6-next-app/blob/main/amplify/backend/function/todoFunction/src/app.js

And here's the front end code:
https://github.com/chrisbonifacio/ampv6-next-app/blob/main/app/page.tsx

Is there anything I should change about my code to be similar enough to yours to reproduce the issue? Or can you provide me a small sample app that reproduces the difference in behavior?

This screenshot you provided doesn't look like what would get logged to the console when catching the error, it looks like the network payload.

Similar to if I check the payloads of my POST and PUT request, which both show the full failed response payload

POST (400 response)

PUT (400 response)

[chrisbonifacio]

One thing that I noticed is that you are sending a msg field in your response payload. Is that consistent with your other routes? I've been sending a message field and they seem to be consumed and logged properly.

But, when I try sending a msg field instead, similar to your route, I don't get the text. Just "Unknown error".

Error caught and logged

Payload

So, I think now I've correctly understood and reproduced the issue finally.

I might've been a little stumped by the screenshots you shared because I assumed you were showing me what the caught and logged error SHOULD look like but now I see you were just showing me the payload for the 400 PUT request 😅 Sorry about that.