Enrich your models - Forest Documentation

Declaring a new model

Whenever you have a new table/collection in your database, you will have to create file to declare it. Here is a template example for a companies table:

SQL
Mongoose

module.exports = (sequelize, DataTypes) => {
  const { Sequelize } = sequelize;
  const Company = sequelize.define('companies', {
    name: {
      type: DataTypes.STRING,
    },
    createdAt: {
      type: DataTypes.DATE,
    },
    ...
  }, {
    tableName: 'companies',
    underscored: true,
    schema: process.env.DATABASE_SCHEMA,
  });

  Company.associate = (models) => {
  };

  return Company;
};

Fields within that model should match your table’s fields as shown in next section.New relationships may be added there:

Company.associate = (models) => {};

You can learn more about relationships on this dedicated page.

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'name': String,
    'createdAt': Date,
    ...
  }, {
    timestamps: false,
  });

  return mongoose.model('companies', schema, 'companies');
};

Fields within that model should match your collection’s fields as shown in next section.New relationships are to be added as properties:

  'orders': [{ type: mongoose.Schema.Types.ObjectId, ref: 'orders' }],
  'customer_id': { type: mongoose.Schema.Types.ObjectId, ref: 'customers' },

You can learn more about relationships on this dedicated page.

When you manually add a new model, you need to configure the permissions for the corresponding collection in the UI (allow record details view, record creation, record edit, etc). By default a new collection is not visible and all permissions are disabled. You can set permissions by going to the Roles settings.

Declaring a new field in a model

Any new field must be added manually within the corresponding model of your /models folder.

SQL
Mongoose

Fields are declared as follows:

createdAt: {
  type: DataTypes.DATE,
},

An exhaustive list of DataTypes can be found in Sequelize documentation.You can see how that snippet fits into your code in the model example above.

Fields are declared as follows:

'createdAt': Date,

An exhaustive list of SchemaTypes can be found in Mongoose documentation.You can see how that snippet fits into your code in the model example above.

Managing nested documents in Mongoose

For a better user experience, flatten nested fields. In v2 see the Flattener plugin.

Lumber introspects your data structure recursively, so nested fields (object in object) are detected any level deep. Your sub-documents (array of nested fields) are detected as well.

Conflicting data types will result in the generation of a mixed type field.

The following model…

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    // Level 0
    'age': Number,
    'id': Number,
    'name': String,
    // Level 1
    'address':{
      'addressDetail': String,
      'area': String,
      'city': String,
      'pincode': Number,
    },
    // Level 2
    'contactDetails':{
      'phone':{
        'homePhone': String,
        'mobilePhone': String,
      },
      'email': String,
    },
    // Related data
    'booksRead':[{
      'name': String,
      'authorName': String,
      'publishedBy': String,
    }],
  }, {
    timestamps: false,
  });
​
  return mongoose.model('testCollection', schema, 'testCollection');
};

…will result in the following interface:

Removing a model

By default all tables/collections in your database are analyzed by Lumber to generate your models. If you want to exclude some of them to prevent them from appearing in your Forest, check out this how-to.

Adding validation to your models

Validation allows you to keep control over your data’s quality and integrity.

If your existing app already has validation conditions, you may - or may not - want to reproduce the same validation conditions in your admin backend’s models. If so, you’ll have to do it manually, using the below examples.

Depending on your database type, your models will have been generated in Sequelize (for SQL databases) or Mongoose (for Mongo databases).

SQL
Mongoose

In Sequelize, you add validation using the validate property:

module.exports = (sequelize, DataTypes) => {
  const Customer = sequelize.define('customers', {
    ...
    'email': {
      type: DataTypes.STRING,
      validate: {
        isEmail: true,
        len: [10,25]
      }
    },
    ...
  },
  ...
  return Customer;
};

The 2 validators above will have the following effect on your email field:

Email too short (not within 10-25 range)

For an exhaustive list of available validators, check out the Sequelize documentation.

In Mongoose, you add validators alongside the type property:

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'createdAt': Date,
    'email': {
      'type': String,
      'minlength': 10,
      'maxlength': 25
    },
    'firstname': String,
    ...
  }

  return mongoose.model('customer', schema, 'customer');
};

This is the effect on your field:

Email is too short (not within 10-25 range)

Mongoose has no build-in validators to check whether a string is an email. Should you want to validate that a content is an email, you have several solutions:

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'createdAt': Date,
    'email': {
      'type': String,
      'match': [/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/, 'Invalid email']
    },
    'firstname': String,
    ...
  }

  return mongoose.model('customer', schema, 'customer');
};

A better yet solution would be to rely on an external library called validator.js which provides many build-in validators:

import { isEmail } from 'validator';

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'createdAt': Date,
    'email': {
      'type': String,
      'validate': [isEmail, 'Invalid email']
    },
    'firstname': String,
    ...
  }

  return mongoose.model('customer', schema, 'customer');
};

You then that any invalid email is refused:

For further details on validators in Mongoose, check out the Mongoose documentation.

Adding a default value to your models

You can choose to add a default value for some fields in your models. As a result, the corresponding fields will be prefilled with their default value in the creation form:

SQL
Mongoose

module.exports = (sequelize, DataTypes) => {
  const Customer = sequelize.define('customers', {
    ...
    'firstname': {
      'type': DataTypes.STRING,
      'defaultValue': 'Marc'
    },
    ...
  },
  ...
  return Customer;
};

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'createdAt': Date,
    'email': {
      'type': String,
      'default': 'Marc'
    },
    'firstname': String,
    ...
  }

  return mongoose.model('customer', schema, 'customer');
};

Adding a hook

Hooks are a powerful mechanism which allow you to automatically trigger an event at specific moments in your records lifecycle. In our case, let’s pretend we want to update a update_count field every time a record is updated:

SQL
Mongoose

To add a beforeSave hook in Sequelize, use the following syntax:

module.exports = (sequelize, DataTypes) => {
  var Order = sequelize.define('orders', {
    ...
    'update_count': {
      'type': DataTypes.INTEGER,
      'defaultValue': 0
    },
    ...
  },
  ...
  Order.beforeSave((order, options) => {
      order.update_count += 1;
    }
  );

  return Order;
};

Every time the order is updated, the updateCount field will be incremented by 1:

The exhaustive list of available hooks in Sequelize are available here.

To add a hook in Mongoose on save event, you may use the following snippet:

module.exports = (mongoose, Mongoose) => {
  const schema = Mongoose.Schema({
    'update_count': {
      'type': Number,
      'default': 0
    },
    ...
  }

  schema.pre('save', async function() {
    const newCount = this.update_count + 1;
    const incrementCount = () => {
      this.set('update_count', newCount);
    };
    await incrementCount();
  });

  return mongoose.model('order', schema, 'order');
};

As mentioned in their documentationPre and post save() hooks are not executed on update(), findOneAndUpdate(), etc.This would only work if you specifically call save in your update method.

​Declaring a new model

​Declaring a new field in a model

​Managing nested documents in Mongoose

​Removing a model

​Adding validation to your models

​

​Adding a default value to your models

​Adding a hook

Declaring a new model

Declaring a new field in a model

Managing nested documents in Mongoose

Removing a model

Adding validation to your models

Adding a default value to your models

Adding a hook