Proposal: Add omit_complexity config flag to skip generation of the body of ComplexityRoot struct and Complexity function

[mariuscraciunescu]

What happened?

When GraphQL schema is really large (~60.000+ lines), the code generated with gqlgen fails to compile with the following error:

<autogenerated>:1: internal compiler error: NewBulk too big: nbit=13244 count=1469951 nword=414 size=608559714
More details about this compiler issue can be found here: golang/go#48375, golang/go#33437

This compilation error is caused by:
type ComplexityRoot struct { ... }
func (e *executableSchema) Complexity(typeName, field string, childComplexity int, rawArgs map[string]interface{}) (int, bool) { ... }

What did you expect?

Code should compile successfully, regardless of the GraphQL schema size.

versions

• v0.17.22

Proposed solution

Introduce a new config flag omit_complexity, which when set to true will skip the generation of the body of these constructs.

The resulting generated code will be:

type ComplexityRoot struct {
  // empty struct
}

func (e *executableSchema) Complexity(typeName, field string, childComplexity int, rawArgs map[string]interface{}) (int, bool) {
  ec := executionContext{nil, e}
  _ = ec

  // switch statement is not generated

  return 0, false
}

This proposal is backwards compatible, won't introduce any breaking changes.