急于使用Feathers JS 4和Objection JS加载-无法读取未定义的属性'get'

Question

我正在使用带有异议ORM的feathers js 4，并尝试创建一个返回异议js模型数据的服务，该数据包括一个渴望加载的BleongsToOneRelation，但我一直得到响应：

无法读取未定义的属性'get'

我已经使用Feathers CLI生成我的服务（和模型），然后进行了修改，以添加关系，如下所示：

devices.model.js

const { Model } = require('objection');

class devices extends Model {

  static get tableName() {
    return 'devices';
  }

  static get jsonSchema() {
    return {
      type: 'object',
      required: ['macAddress'],

      properties: {
        macAddress: { type: 'string' },
        circuitId: { type: 'integer' },
      }
    };
  }

  static get relationMappings() {

    const Circuit = require('./circuits.model')();
    const DeviceType = require('./device-types.model')();

    return {
      circuit: {
        relation: Model.BelongsToOneRelation,
        modelClass: Circuit,
        join: {
          from: 'devices.circuitId',
          to: 'circuits.id'
        }
      }
    };
  }

  $beforeInsert() {
    this.createdAt = this.updatedAt = new Date().toISOString();
  }

  $beforeUpdate() {
    this.updatedAt = new Date().toISOString();
  }
}

module.exports = function (app) {
  const db = app.get('knex');

  db.schema.hasTable('devices').then(exists => {
    if (!exists) {
      db.schema.createTable('devices', table => {
        table.increments('id');
        table.string('macAddress');
        table.integer('circuitId');
        table.timestamp('createdAt');
        table.timestamp('updatedAt');
      })
        .then(() => console.log('Created devices table')) // eslint-disable-line no-console
        .catch(e => console.error('Error creating devices table', e)); // eslint-disable-line no-console
    }
  })
    .catch(e => console.error('Error creating devices table', e)); // eslint-disable-line no-console

  return devices;
};

device.class.js

const { Devices } = require('./devices.class');
const createModel = require('../../models/devices.model');
const hooks = require('./devices.hooks');

module.exports = function (app) {
  const options = {
    Model: createModel(app),
    paginate: app.get('paginate'),
    whitelist: ['$eager', '$joinRelation', '$modifyEager'],
    allowedEager: ['circuit']
  };

  // Initialize our service with any options it requires
  app.use('/devices', new Devices(options, app));

  // Get our initialized service so that we can register hooks
  const service = app.service('devices');

  service.hooks(hooks);
};

然后我使用http://localhost:3030/devices？$ eager = circuit调用/ devices GET请求>

结果是：

{
    "name": "GeneralError",
    "message": "Cannot read property 'get' of undefined",
    "code": 500,
    "className": "general-error",
    "data": {},
    "errors": {}
}
曾尝试向devices.class.js添加自定义find（）方法，但这似乎无济于事。

我在这里搜索了类似的问题，并阅读了feathers-objection docs，但看不到我所缺少的内容。任何帮助将不胜感激。

我正在将羽毛js 4与异议ORM配合使用，并尝试创建一个返回异议js模型数据的服务，该数据包括一个渴望加载的BleongsToOneRelation，但我一直得到响应：...

Answer 1

app变量之类的声音未定义。如果添加断点并检查调用堆栈以了解原因，调试器可能会为您提供很多帮助。也许您没有将其正确地传递到模块中。