![Subscriptions using built-in SubscriptionServer error: client gets "Cannot read property 'headers' of undefined" · Issue #1537 · apollographql/apollo- server · GitHub Subscriptions using built-in SubscriptionServer error: client gets "Cannot read property 'headers' of undefined" · Issue #1537 · apollographql/apollo- server · GitHub](https://user-images.githubusercontent.com/19241756/52901280-a5902c00-3212-11e9-8f8a-a7248e214524.png)
Subscriptions using built-in SubscriptionServer error: client gets "Cannot read property 'headers' of undefined" · Issue #1537 · apollographql/apollo- server · GitHub
![throwing AuthenticationError should set the response status to 401 Unauthorized · Issue #1709 · apollographql/apollo-server · GitHub throwing AuthenticationError should set the response status to 401 Unauthorized · Issue #1709 · apollographql/apollo-server · GitHub](https://user-images.githubusercontent.com/33569/45916168-6520b380-be16-11e8-8bc4-28658f2924f5.png)
throwing AuthenticationError should set the response status to 401 Unauthorized · Issue #1709 · apollographql/apollo-server · GitHub
![Unhandled Rejection (Error): GraphQL error: Authentication required · Issue #6070 · apollographql/apollo-client · GitHub Unhandled Rejection (Error): GraphQL error: Authentication required · Issue #6070 · apollographql/apollo-client · GitHub](https://user-images.githubusercontent.com/9727036/80531251-4f675e80-8968-11ea-811f-c35d22fd3780.png)
Unhandled Rejection (Error): GraphQL error: Authentication required · Issue #6070 · apollographql/apollo-client · GitHub
![Validations for multiple fields in Apollo Server 2.0 · Issue #1166 · apollographql/apollo-server · GitHub Validations for multiple fields in Apollo Server 2.0 · Issue #1166 · apollographql/apollo-server · GitHub](https://user-images.githubusercontent.com/441418/46126409-7df2f400-c270-11e8-8e57-b7a59249efc7.png)
Validations for multiple fields in Apollo Server 2.0 · Issue #1166 · apollographql/apollo-server · GitHub
![Unhandled Rejection (Error): GraphQL error: Authentication required · Issue #6070 · apollographql/apollo-client · GitHub Unhandled Rejection (Error): GraphQL error: Authentication required · Issue #6070 · apollographql/apollo-client · GitHub](https://user-images.githubusercontent.com/3206387/77244811-a8313200-6c19-11ea-9adf-5d91b7056bc4.png)