formhandler.js

/*
Copyright 2018 Ryozuki

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

/**
 * A Generic Form Handler Class
 */
class FormHandler {
  /**
   * The form constructor
   * @param {*} formID The form id
   * @param {*} url The url to perfom the action on.
   * @param {*} type The http request type, e.g POST, GET, PUT
   */
  constructor (formID, url, type) {
    this.id = formID
    this.url = url
    this.type = type
    this.form = $(this.id)
    this.onSuccessCallbacks = []
    this.onFailureCallbacks = []
    this.onInternalCallbacks = []
    this.onGeneralCallbacks = []
    this.beforeSendCallbacks = []

    if (!this.form.length) {
      throw new Error('Error finding the form DOM.')
    }

    // Subscribe to form submit event
    this.form.submit(e => {
      e.preventDefault()
      let ajax = this.buildAjax()
      $.ajax(ajax)
    })
  }

  buildAjax () {
    return {
      url: this.url,
      type: this.type,
      data: this.objectifyForm(),
      beforeSend: () => {
        this.beforeSendCallbacks.forEach(x => x(this))
      },
      success: (res, status, xhr) => {
        this.onSuccessCallbacks.forEach(x => x(xhr.status, xhr))
        this.onGeneralCallbacks.forEach(x => x(xhr.status, xhr))
      },
      error: (res) => {
        if (res.status === 500) {
          this.onInternalCallbacks.forEach(x => x(res.status, res))
        }
        this.onFailureCallbacks.forEach(x => x(res.status, res))
        this.onGeneralCallbacks.forEach(x => x(res.status, res))
      }
    }
  }

  objectifyForm () {
    var formArray = this.form.serializeArray()
    var returnArray = {}
    for (var i = 0; i < formArray.length; i++) {
      returnArray[formArray[i]['name']] = formArray[i]['value']
    }
    return returnArray
  }

  /**
   * Executed before sending the request
   * @param {Function} callback The callback, a FormHandler is passed as argument
   */
  beforeSend (callback) {
    this.beforeSendCallbacks.push(callback)
  }

  /**
   * Called when a response, callback args are (code, response)
   * @param {function} callback The callback
   */
  onResponse (callback) {
    this.onGeneralCallbacks.push(callback)
  }

  /**
   * Called on a success http response, callback args are (code, response)
   * @param {function} callback The callback
   */
  onSuccess (callback) {
    this.onSuccessCallbacks.push(callback)
  }

  /**
   * Called on a failure http response, callback args are (code, response)
   * @param {function} callback The callback
   */
  onFailure (callback) {
    this.onFailureCallbacks.push(callback)
  }

  /**
   * Called on a internal error http response, callback args are (code, response)
   * @param {function} callback The callback
   */
  onInternal (callback) {
    this.onInternalCallbacks.push(callback)
  }
}