[Q] Is type assertion check needed for resolver params?

[mrdulin]

Type cast code: https://github.com/graphql-go/graphql/blob/master/examples/todo/main.go#L156

idQuery, isOK := params.Args["id"].(string)

args for type: https://github.com/graphql-go/graphql/blob/master/examples/todo/main.go#L149

Args: graphql.FieldConfigArgument{
    "id": &graphql.ArgumentConfig{
        Type: graphql.String,
    },
},

Since the arguments validation is done in GraphQL schema layer.The id parameter must be a string type in resolver. So I think it's unnecessary to check isOk variable. Am I correct?

[Fontinalis]

In this specific case, since the id argument could be null, isOk can be either true or false. But if you specify the argument's type as String!, which is a non null string type, you'll be right and isOk should be always true.

[mrdulin]

@Fontinalis Thanks. So I am thinking can this package can do this type assertion based on GraphQL fields' type for developer. So we don't need write this thing again and again.