Unique email validation before create new record

Am trying to validate Email already exists validation in Bookshelf.js when creating new record.

I found one solution here github but its not working, even i tried with Promise

User = bookshelf.Model.extend({
  tableName: 'users',
  initialize: function() {
    this.on('saving', this._assertEmailUnique);
  },
  _assertEmailUnique: function(model, attributes, options) {
    if (this.hasChanged('email')) {
      return this
        .query('where', 'email', this.get('email'))
        .fetch(_.pick(options, 'transacting'))
        .then(function (existing) {
          if (!existing) throw new Error('duplicate email');
        });
    }
  }
});

For Model validation currently am using Joi, looks like Joi also not supporting for custom validation for this. Am using Postgres Database. There is any other way to do it… Please help…

[rhys-vdw]

Just put a unique constraint on the column…

On Wed, Jul 6, 2016, 8:51 PM raj-optisol [e-mail] wrote:

Closed #1313 https://github.com/tgriesser/bookshelf/issues/1313.

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/tgriesser/bookshelf/issues/1313#event-714168813, or mute the thread https://github.com/notifications/unsubscribe/AAyLWRUk6vWS6dE_Ma73suSk3WczZw8Lks5qS4ivgaJpZM4JDqK6 .

[aj0strow]

Here’s what I’m using. Start with a unique constraint.

// migration file

knex.table("table_name", t => {
  t.unique("unique_column_name")
  t.unique("compound_index", "part_two")
})

Then count duplicates on each create or save, respecting transactions, and filtering out the current model from the count.

function assertUnique(/* columns */) {
  const columns = _.toArray(arguments)
  if (columns.length === 0) {
    throw new Error("please pass unique columns")
  }
  return function(model, attributes, options) {
    const hasChanged = _.some(columns, column => {
      return model.hasChanged(column)
    })
    if (model.isNew() || hasChanged) {
      return this.constructor.query(q => {
        columns.forEach(column => {
          q.where(column, '=', model.get(column))
        })
        if (!model.isNew()) {
          q.where(model.idAttribute, '<>', model.id)
        }
      })
      .count({ transacting: options.transacting })
      .then(n => {
        if (n > 0) {
          return bluebird.reject({
            name: "DuplicateError",
            message: columns.join(", ")
          })
        }
      })
    }
  }
}

Then run the assertion for any model with unique constraints.

// users
  this.on("saving", assertUnique("email"))

// posts
  this.on("saving", assertUnique("md5_hash"))
  this.on("saving", assertUnique("user_id", "title"))

It should work for most use cases.