onCreate subscription returns null through `aws-amplify` API, but not through AppSync

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• 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

Not applicable

Amplify APIs

GraphQL API

Amplify Categories

api

Environment information

# Put output below this line
  System:
    OS: macOS 11.5.2
    CPU: (8) x64 Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz
    Memory: 21.10 MB / 16.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 16.0.0 - ~/.nvm/versions/node/v16.0.0/bin/node
    Yarn: 1.22.5 - /usr/local/bin/yarn
    npm: 7.19.0 - ~/.nvm/versions/node/v16.0.0/bin/npm
    Watchman: 2021.06.07.00 - /usr/local/bin/watchman
  Browsers:
    Chrome: 92.0.4515.159
    Edge: 92.0.902.78
    Firefox: 84.0.2
    Safari: 14.1.2
  npmPackages:
    @creativelayer/chalk-icons: ^1.1.2 => 1.1.2
    @creativelayer/chalk-ui: ^1.36.0 => 1.36.1
    @types/jest: ^26.0.24 => 26.0.24
    @typescript-eslint/eslint-plugin: ^4.29.3 => 4.29.3
    @typescript-eslint/parser: ^4.29.3 => 4.29.3
    @vitejs/plugin-vue: ^1.4.0 => 1.4.0
    @vue/compiler-sfc: ^3.2.4 => 3.2.4
    @vue/eslint-config-standard: ^6.1.0 => 6.1.0
    @vue/eslint-config-typescript: ^7.0.0 => 7.0.0
    @vue/test-utils: ^2.0.0-rc.12 => 2.0.0-rc.12
    @xstate/vue: ^0.8.0 => 0.8.0
    autoprefixer: ^10.3.2 => 10.3.2
    aws-amplify: ^4.2.4 => 4.2.4
    buffer: ^6.0.3 => 6.0.3 (4.9.2)
    cypress: ^8.3.0 => 8.3.0
    dynamic-import-polyfill: ^0.1.1 => 0.1.1
    eslint: ^7.32.0 => 7.32.0
    eslint-plugin-cypress: ^2.11.3 => 2.11.3
    eslint-plugin-import: ^2.24.1 => 2.24.1
    eslint-plugin-jest: ^24.4.0 => 24.4.0
    eslint-plugin-vue: ^7.16.0 => 7.16.0
    jest: ^26.6.3 => 26.6.3
    mockdate: ^3.0.5 => 3.0.5
    postcss: ^8.3.6 => 8.3.6
    tailwindcss: ^2.2.7 => 2.2.7
    ts-jest: ^26.5.5 => 26.5.6
    typescript: ^4.3.5 => 4.3.5
    vite: ^2.5.0 => 2.5.0
    vue: ^3.2.4 => 3.2.4
    vue-jest: ^5.0.0-alpha.10 => 5.0.0-alpha.10
    vue-loader: ^16.5.0 => 16.5.0
    vue-router: ^4.0.11 => 4.0.11
    vue-router-mock: 0.0.3 => 0.0.3
    xstate: ^4.23.1 => 4.23.1
  npmGlobalPackages:
    @aws-amplify/cli: 5.2.1
    np: 7.5.0
    npm: 7.19.0

Describe the bug

When subscribing to a subscription with the graphqlOperation, and not specifying any variables, the returned data is always null, whereas subscribing in AppSync to the same thing without variables does actually yield the proper result.

Expected behavior

To be able to subscribe without variables and still get data returned.

Reproduction steps

Subscribe to something like onCreateTodo without any parameters, this should fire every time a todo is created, regardless of condition.

In AppSyn the result will be correct, in Amplify it won’t:

    const subscription = API.graphql(
      graphqlOperation(subscriptions.onCreateTodo)
    ).subscribe({
      next: (data) => console.log(data),
      error: error => console.warn(error),
    })

data will be data: { onCreateBusiness: null } through API.graphql

Code Snippet

    const subscription = API.graphql(
      graphqlOperation(subscriptions.onCreateTodo)
    ).subscribe({
      next: (data) => console.log(data),
      error: error => console.warn(error),
    })

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

[TheDutchCoder]

@chrisbonifacio Okay that seems to work now indeed, that’s good!

[TheDutchCoder]

@TheDutchCoder I noticed that you have a createdAt field in your Business model. I believe AppSync handles createdAt and updatedAt automatically for you. Could you try removing that field and see if you receive the actual data from the payload then?

I think those were required to generate the proper types with codegen. I’m actually in the process of moving the whole project over to TS so hopefully that will remedy that problem.

I’ll ping you when that’s done and then we can explore this further. Appreciate the help!