aws-mobile-appsync-sdk-js: AppSync generated graphql subscription not running

Appsync generated graphql subscription is not working (tested using console). I think this is a big issue because when you start learning you expect at least generated things to work

//fails, generated by appsync subscription OnCreateNotes($id: ID, $title: String, $body: String) { onCreateNotes(id: $id, title: $title, body: $body) { id title body } }

//works subscription onNewCreateNotes { onNewCreateNotes { __typename id title body } }

About this issue

Original URL
State: open
Created 5 years ago
Reactions: 10
Comments: 26 (7 by maintainers)

Most upvoted comments

not working for me still, any workaround for this ?

JeetChhatrala on Aug 24, 2021

Same problem here, was this solved? I can’t get anything as passing variables into subscribeToMore, even if I use undefined/null value, nothing happened.

I’m kind of wondering if the input different between mutation and subscription will cause error?

mutation --> createNotes(input: CreateNotesInput!): Notes subscription --> onCreateNotes(id: ID, title: String, body: String): Notes

ArronHsiao on Jul 23, 2019

Short explanation: I think the subscription in the screenshot is evaluating to onCreateNotes(id: null, title: null, body: null). Therefore, the subscription is looking for created Notes which have id = null, title = null, and body = null.

Longer Answer: The subscription has 3 query variables defined for the operation ($id, $title, and $body). Since id, title and body are defined and they are being used as input parameters to the subscription, the graphQL engine will try to coerce those values by looking into the Query Variables passed in (bottom left corner of the page). In the screenshot, there is a variable value for createnotesinput, but there are no variables passed in for id, title, or body. Therefore, a default value is probably inserted for id, title, and body. The default value, in this case, is probably null.

michael-b-willingham on Jan 17, 2019