Class HasOne

lib/associations/has-one.js:17–274

* One-to-one association * * In the API reference below, add the name of the association to the method, e.g. for `User.hasOne(Project)` the getter will be `user.getProject()`. * This is almost the same as `belongsTo` with one exception - The foreign key will be defined on the target model. * *

 * @see {@link Model.hasOne}
 */
class HasOne extends Association {
  constructor(source, target, options) {
    super(source, target, options);

    this.associationType = 'HasOne';
    this.isSingleAssociation = true;
    this.foreignKeyAttribute = {};

    if (this.as) {
      this.isAliased = true;
      this.options.name = {
        singular: this.as
      };
    } else {
      this.as = this.target.options.name.singular;
      this.options.name = this.target.options.name;
    }

    if (_.isObject(this.options.foreignKey)) {
      this.foreignKeyAttribute = this.options.foreignKey;
      this.foreignKey = this.foreignKeyAttribute.name || this.foreignKeyAttribute.fieldName;
    } else if (this.options.foreignKey) {
      this.foreignKey = this.options.foreignKey;
    }

    if (!this.foreignKey) {
      this.foreignKey = Utils.camelize(
        [
          Utils.singularize(this.options.as || this.source.name),
          this.source.primaryKeyAttribute
        ].join('_')
      );
    }

    if (
      this.options.sourceKey
      && !this.source.rawAttributes[this.options.sourceKey]
    ) {
      throw new Error(`Unknown attribute "${this.options.sourceKey}" passed as sourceKey, define this attribute on model "${this.source.name}" first`);
    }

    this.sourceKey = this.sourceKeyAttribute = this.options.sourceKey || this.source.primaryKeyAttribute;
    this.sourceKeyField = this.source.rawAttributes[this.sourceKey].field || this.sourceKey;
    this.sourceKeyIsPrimary = this.sourceKey === this.source.primaryKeyAttribute;

    this.associationAccessor = this.as;
    this.options.useHooks = options.useHooks;

    if (this.target.rawAttributes[this.foreignKey]) {
      this.identifierField = this.target.rawAttributes[this.foreignKey].field || this.foreignKey;
    }

    // Get singular name, trying to uppercase the first letter, unless the model forbids it
    const singular = _.upperFirst(this.options.name.singular);

    this.accessors = {
      get: `get${singular}`,
      set: `set${singular}`,