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Unhelpful Error Message: Cannot read property 'length' of undefined

See original GitHub issue

$ amplify push ✔ Successfully pulled backend environment dopry from the cloud. Current Environment: dopry

Category Resource name Operation Provider plugin
? Are you sure you want to continue? Yes
✖ An error occurred when pushing the resources to the cloud

Cannot read property ‘length’ of undefined An error occurred during the push operation: Cannot read property ‘length’ of undefined

What does this error mean? After trying all the sub-commands amplify push function shows me

Cannot read property 'length' of undefined
TypeError: Cannot read property 'length' of undefined
    at C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\node_modules\amplify-provider-awscloudformation\src\push-resources.ts:802:57
    at Array.forEach (<anonymous>)
    at C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\node_modules\amplify-provider-awscloudformation\src\push-resources.ts:786:15
    at Array.forEach (<anonymous>)
    at formNestedStack (C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\node_modules\amplify-provider-awscloudformation\src\push-resources.ts:783:14)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
    at Object.run (C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\node_modules\amplify-provider-awscloudformation\src\push-resources.ts:216:29)
    at async Promise.all (index 0)
    at providersPush (C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\src\extensions\amplify-helpers\push-resources.ts:90:3)
    at AmplifyToolkit.pushResources [as _pushResources] (C:\Users\dopry\AppData\Roaming\npm\node_modules\@aws-amplify\cli\src\extensions\amplify-helpers\push-resources.ts:66:7)

What length of what exactly? Which function resource has a problem? This error message is not helpful.

Processing each template and component should be wrapped in a try/catch and you should let developers know what is failing.

Issue Analytics

  • State:closed
  • Created 3 years ago
  • Comments:7 (4 by maintainers)

github_iconTop GitHub Comments

1reaction
doprycommented, Jan 19, 2021

not like it makes a difference since you can go straight to https://github.com/aws-amplify/amplify-cli/blob/b5f917a81524feb64ec7e674c6213cb47fd7794c/packages/amplify-provider-awscloudformation/src/push-resources.ts#L800 and see the code accessing .length on the potentially empty attributes array. lazy

but node 14/LTS and amplify 4.41.2

0reactions
github-actions[bot]commented, May 28, 2021

This issue has been automatically locked since there hasn’t been any recent activity after it was closed. Please open a new issue for related bugs.

Looking for a help forum? We recommend joining the Amplify Community Discord server *-help channels for those types of questions.

Read more comments on GitHub >

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