How to create Field with OneToMany

I try

 @OneToMany(type => Family, family => family.childhood)
    @Field({type: () => Family})
    family: Family[];

Error: @ObjectType Family.childhood: Validation of type failed. Resolved type for @Field must be GraphQLOutputType.

[pie6k]

Seems you have circular relationship (Childhood > Family > Childhood > Family) etc. In such case, you have to define type as function. (http://siawyoung.com/coding/javascript/circular-references-graphql-type-definitions.html)

Try to modify:

    @ManyToOne(type => Childhood, childhood => childhood.family)
    @Field()
    childhood: Childhood;

to

    @ManyToOne(type => Childhood, childhood => childhood.family)
    @Field({ type: () => Childhood })
    childhood: Childhood;

Also change

    @OneToMany(type => Family, family => family.childhood)
    @Field()
    family: Family[];

to

    @OneToMany(type => Family, family => family.childhood)
    @Field({ type: () => [Family] })
    family: Family[];

And let me know if that helps.

Note that if you use array types (eg. Family[]) you’d have to set type manually anyway as typescript is not able to guess type of array item.

[pie6k]

@korolariya you don’t need to define function that returns your Childhoods. Typeorm is handling it by itself.

So basically you could simply

@ManyToOne(type => Childhood, childhood => childhood.family)
@Field({type: () => Childhood})
childhood: Childhood;

If you’d need to add some custom logic you could do this like:

    @Field({type: () => Childhood})
    async childhood() {
        return Childhood.createQueryBuilder().relation("family").of(this).loadOne();
        // or some custom logic
    };

But it might not be needed propably in your case. In case you’d like to learn more about relational queries: http://typeorm.io/#/relational-query-builder