How to fix 'Cannot read property 'joinColumns' of undefined' error in EntitySchema and Graphql

Question

I want to have a one-to-many relation in User to Keyword Table and in Keyword Table a many-to-one relation.

I don´t use TypeScript because that i have use the EntitySchema from Typeorm.

This was my entities:

import { EntitySchema } from 'typeorm';

export default new EntitySchema({
  name: 'User',
  columns: {
    id: {
      primary: true,
      type: Number,
      generated: true,
    },
    firstname: {
      type: 'varchar',
    },
    lastname: {
      type: 'varchar',
    },
    email: {
      type: 'varchar',
      default: null,
    },
    auth: {
      type: 'varchar',
      nullable: true,
    },
  },
  relations: {
    keywords: {
      target: 'Keyword',
      type: 'one-to-many',
    },
  },
});

import { EntitySchema } from 'typeorm';

export default new EntitySchema({
  name: 'Keyword',
  columns: {
    id: {
      primary: true,
      type: Number,
      generated: true,
    },
    name: {
      type: 'varchar',
    },
    created_at: {
      type: Date,
    },
  },
  relations: {
    user: {
      target: 'User',
      type: 'many-to-one',
    },
  },
});

The Error from GraphQL "Cannot read property 'joinColumns' of undefined"

Answer 1

There are two things missing in your EntitySchema: You need to specify the JoinColumn and the inverse side for the OneToMany relation. So this should work:

export default new EntitySchema({
  name: 'User',
  ...
  relations: {
    keywords: {
      target: 'Keyword',
      type: 'one-to-many',
      inverseSide: 'user',
    },
  },
});

export default new EntitySchema({
  name: 'Keyword',
  ...
  relations: {
    user: {
      target: 'User',
      type: 'many-to-one',
      joinColumn: true,
    },
  },
});