Error Handling

You can configure your schema to rescue application errors during field resolution. Errors during batch loading will also be rescued.

Thanks to @exAspArk for the graphql-errors gem which inspired this behavior and @thiago-sydow who suggested and implementation like this.

Add error handlers

Handlers are added with rescue_from configurations in the schema:

class MySchema < GraphQL::Schema
  # ...

  rescue_from(ActiveRecord::RecordNotFound) do |err, obj, args, ctx, field|
    # Raise a graphql-friendly error with a custom message
    raise GraphQL::ExecutionError, "#{field.type.unwrap.graphql_name} not found"
  end

  rescue_from(SearchIndex::UnavailableError) do |err, obj, args, ctx, field|
    # Log the error
    Bugsnag.notify(err)
    # replace it with nil
    nil
  end
end

The handler is called with several arguments:

Inside the handler, you can: