[Predictions]: CallBack doesn't return in convert() when URLError occurs

[618coffee]

Describe the bug
Using provisioned AWS Transcribe resource in an unsupported region and call Amplify.Predictions.convert(), CallBack which contains error message doesn't return.

To Reproduce
Steps to reproduce the behavior:

1. Create a Predictions Sample App
2. Follow https://docs.amplify.aws/lib/predictions/transcribe/q/platform/ios to provision AWS Transcribe resource in eu-west-2 region
3. Call Amplify.Predictions.convert() to transcribe an audio file
4. The call back is not returning (neither success case nor failure case)

Expected behavior
Failure message should be returned

Environment(please complete the following information):

• Amplify Framework Version: 1.0.4
• Dependency Manager: Cocoapods
• Swift Version : 5.0

Device Information (please complete the following information):

• Device: Simulators
• iOS Version: iOS

[618coffee]

This might not be an issue anymore:

1. Amazon Transcribe is now available in four more regions according to this link
2. Backend resource fail to be provisioned in the rest of unsupported regions.

I tried to provision backend in unsupported region.

eu-north-1(Stockholm)
amplify init fails by showing up error message:

CREATE_FAILED      predictionstranscription4509dade        AWS::CloudFormation::Stack Wed Nov 11 2020 22:46:47 GMT-0800 (Pacific Standard Time) Template error: Unable to get mapping for RegionMapping::eu-north-1::transcription


Resource is not in the state stackUpdateComplete
An error occurred during the push operation: Resource is not in the state stackUpdateComplete

as-south-1(Cape Town), eu-south-1(Milan)
amplify push fails by showing up error message like:

An error occurred when creating the CloudFormation stack
 Unable to get mapping for RegionMapping::ap-northeast-3::transcription
✖ Root stack creation failed
init failed
InvalidClientTokenId: The security token included in the request is invalid.
    at Request.extractError (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/protocol/query.js:50:29)
    at Request.callListeners (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:106:20)
    at Request.emit (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:78:10)
    at Request.emit (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:688:14)
    at Request.transition (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:22:10)
    at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/state_machine.js:14:12)
    at /usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/state_machine.js:26:10
    at Request.<anonymous> (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:38:9)
    at Request.<anonymous> (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/request.js:690:12)
    at Request.callListeners (/usr/local/lib/node_modules/@aws-amplify/cli/node_modules/aws-sdk/lib/sequential_executor.js:116:18) {
  code: 'InvalidClientTokenId',
  time: 2020-11-12T16:52:33.854Z,
  requestId: '618c66b4-b147-4c36-9836-319869be963d',
  statusCode: 403,
  retryable: false,
  retryDelay: 49.850930757515414
}

[618coffee]

On the time(07/29/2020) when I created this issue, provisioning AWS Transcribe backend resource in unsupported region was successful. But it fails now, for example in eu-north-1(Stockholm) region.

What I tried out is to provision Auth in eu-north-1(Stockholm) and put predictions configuration info in amplifyconfiguration.json, I can see

Connection 1: received failure notification
Connection 1: failed to connect 12:8, reason -1
Connection 1: encountered error(12:8)

and

Task <4DBD2D38-595F-4EDA-A9EF-6BCD062151DD>.<1> HTTP load failed, 0/0 bytes (error code: -1003 [12:8])

printed out when calling Amplify.Predictions.convert()

Also Below message prints out when trying to call Amplify.Predictions.convert() the second time.

error: The operation couldn’t be completed. (Amplify.PredictionsError error 4.)

I don't quite remember what message I saw four months ago. But I guess these messages might also showed up at that time.

[palpatim]

Released in 1.5.1