Make types non-nullable by default

[r-marques]

Description

There is a discrepancy between how the graphql types are generated during scaffolding and how they are read during code generation.

If I have an abi like this https://github.com/nevermined-io/contracts/blob/5b8680b3c581ec50877ed8451c623c8480ac000d/artifacts/AccessProofCondition.mumbai.json#L3-L52 and using the cli to run graph init with --index-events it will generate the following schema.

type AccessProofConditionFulfilled @entity {
  id: ID!
  _agreementId: Bytes! # bytes32
  _origHash: BigInt! # uint256
  _buyer: [BigInt]! # uint256[2]
  _provider: [BigInt]! # uint256[2]
  _cipher: [BigInt]! # uint256[2]
  _proof: Bytes! # bytes
  _conditionId: Bytes! # bytes32
}

Now during code generation when the uint256[] types are converted from graphql it complains that lists cannot have nullable types.

Changing a default is probably not the best idea but I'm glad to help if someone points me in the right direction

[evaporei]

You're right, this makes sense, however even though it's on the same file, PR #802 it's not about the same issue.

I'll merge and release that one and take this bug report as an issue to resolve (that I intend on working right now).

[evaporei]

To solve the issue, this file should be changed instead. So that schema.graphql gets generated correctly.

I've created an issue to track this: #808

[YaroShkvorets]

Implemented in #1058