Request: Global Error Handler

[thanpolas]

Hello,

We want to enforce a global error handler across all our graphql mutations and queries so as to apply specific business logic before the error reaches the client.

So far I have only come up with the kadirahq/graphql-errors package, which basically walks all the fields of all the type definitions and wraps the resolve method of each one.

Is that what we only have today? Am I missing something? Would you consider adding such a feature, a global error handler?

[baer]

There are a couple of issues on this project to explore different error handling. See #284 #402

I'm not completely sure what types of business logic you're talking about applying but the formatError option in express-graphql will catch and aggregate errors thrown during resolution. You can use that function to log or format before they reach the client.

[leebyron]

This is already possible! Thanks @baer for some pointers to how you can implement this.

Since this package does not deal with sending results to a client, then the expectation is that you would place any post-processing between the output of any calls to this package and before serializing and sending to a client.

For example, in express-graphql, as @baer explained, a global error handler can be provided as an option - here is how that ends up being used.