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      Mobify Progressive Web SDK Docs

      Important: We've removed this article from the site navigation because many of the source code examples in it are out of date, but we've left it here in case you still need to refer to it.

      The Cookie Manager is a singleton class that manages cookies. It helps React components to be aware of changes in a cookie's value.

      Why a Cookie Manager?

      Browser cookies are essentially a key-value store for the browser that is separated from the PWA. The PWA is a reactive application but there is no way to know when a cookie is updated at any given time. We introduced the Cookie Manager to help facilitate that.


      import React, {Component} from 'react'
      import cookieManager from 'progressive-web-sdk/dist/utils/cookie-manager'
      const MY_COOKIE_NAME = 'my_cookie_name'
      class MyComponent extends Component {
          constructor(props) {
              this.state = {
                  splitValue: cookieManager.get(MY_COOKIE_NAME)
          componentDidMount() {
              this.cookieSubscriber = cookieManager.subscribe(
                  (splitValue) => {
                      // This gets called when my_cookie_name is updated
                      // splitValue will be the new cookie value
                      // Make sure we don't setState when the new value is the same
                      // as the old value
                      if (this.state.splitValue !== splitValue) {
          componentWillUnmount() {
              // Stop getting notification when component gets unmount
          render() {
              return (

      The above setup allows a React component to listen for a particular cookie's value.

      Triggering a cookie update

      Traditionally, browsers get updated cookie settings through a page refresh. However, this update mechanism is no longer available to single-page apps because page refreshes don't happen. Sometimes you'll still need to update cookies, usually to integrate with one of the following types of third-party scripts:

      • Social logins
      • Multi-variate platforms
      • Recommendation systems
      • Campaign platforms

      To trigger a cookie update within your PWA, place the following code where appropriate:

      import cookieManager from 'progressive-web-sdk/dist/utils/cookie-manager'

      An appropriate time to trigger this function would be when:

      • After making an AJAX request to a back-end API
      • A third-party script has began executing and you are expecting a cookie change
      • A third-party script that is aware of PWA navigation and will place a cookie when conditions are meet


      set(cookieName, cookieValue, domain, lifetime)

      Sets a cookie

      parameter type description
      cookieName String Name of the cookie
      cookieValue String Value of the cookie
      domain String Domain of the cookie
      lifetime Integer Lifetime duration in milliseconds to the future or leave it null for a session cookie

      Returns nothing

      get(cookieName, defaultValue)

      Get the cookie value if exist, otherwise return the default value

      parameter type description
      cookieName String Name of the cookie
      defaultValue String Default value of the cookie

      Returns String

      subscribe(cookieName, updateCallback)

      Subscribe to the specified cookie

      parameter type description
      cookieName String Name of the cookie
      updateCallback Function A callback when Cookie Manager detects an updated value for this cookie

      Returns CookieSubscriber


      import cookieManager from 'progressive-web-sdk/dist/utils/cookie-manager'
      // To listen for cookie value change
      const cookieSubscriber = cookieManager.subscribe(
          (splitValue) => {
              // splitValue will be the new cookie value
      // To stop listening for cookie value change


      Perform an update check on subscribed cookies. Cookie Manager will call the updateCallback for each cookie subscribers when the cookie in inquiry exists. It is up to each cookie subscriber to determine what to do when the updated cookie value is the same as the last cookie value.



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