Error Starting Server Due to mappedBy reference in module models

[vholik]

Bug report

Error starting server
Error: Loaders for module VehicleModuleService failed: VehicleYear.models has unknown 'mappedBy' reference: VehicleModel.vehicle_year

Describe the bug

I encountered an error when starting the server, related to the relationships between my models in one vehicle module. The error specifically points to an unknown mappedBy reference between VehicleYear and VehicleModel.

brand.ts

import { model } from "@medusajs/framework/utils";
import { VehicleYear } from "./year";

export const Brand = model.define("brand", {
  id: model
    .id({
      prefix: "bra",
    })
    .primaryKey(),
  name: model.text(),
  logo: model.text().nullable(),
  years: model.hasMany(() => VehicleYear),
});

year.ts

import { model } from "@medusajs/framework/utils";
import { Brand } from "./brand";
import { VehicleModel } from "./model";

export const VehicleYear = model.define("vehicle_year", {
  id: model
    .id({
      prefix: "year",
    })
    .primaryKey(),
  year: model.number(),
  brand: model.belongsTo(() => Brand, {
    mappedBy: "years",
  }),
  models: model.hasMany(() => VehicleModel),
});

model.ts

import { model } from "@medusajs/framework/utils";
import { VehicleYear } from "./year";
import { VehicleVariant } from "./variant";

export const VehicleModel = model.define("vehicle_model", {
  id: model
    .id({
      prefix: "model",
    })
    .primaryKey(),
  name: model.text(),
  years: model.belongsTo(() => VehicleYear, {
    mappedBy: "models",
  }),
});

I suspect the error might be due to having both model.belongsTo and model.hasMany in the same models (VehicleYear and VehicleModel).

System information

Medusa version (including plugins):
Node.js version:
Database:
Operating system:
Browser (if relevant):

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Expected behavior

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[thetutlage]

Hello @vholik

Sorry for the late reply. Actually, the error you get is because the DML is not able to discover the inverse of the relationship using the default naming convention.

So there are two ways to fix it.

• First, we either stick to be conventional naming. In that case, the property name on the VehicleModel should be vehicle_year and not year.

  - years: model.belongsTo(() => VehicleYear, {
  + vehicle_year: model.belongsTo(() => VehicleYear, {
    mappedBy: "models",
  }),

• Or we define a custom mappedBy property when defining the relationship on the VehicleYear model.

  models: model.hasMany(() => VehicleModel, {
  +  mappedBy: "years"
  }),