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    0.0.4 • Public • Published

    Cookie Manager

    License: MIT Build Status Known Vulnerabilities

    Cookie Manager is a Javascript library for dealing with cookie compliance.

    It can handle removing cookies which the user does not consent to or those that are not defined in the manifest. It can also handle the storing of user preferences when it comes to cookies, and includes the functionality to display a banner when no preferences have been set.

    This repo is originally based on the fantastic work of the DVSA team and their Cookie Manager, found here. This fork is modified to work with accept-reject style banners, and also those which have hide/dismiss functionality. Preferably to be used in conjuction with the GDS Cookie Banner component.



    npm install --save @hmcts/cookie-manager


    Include the cookie-manager.js script on your web pages:

    <script src="./cookie-manager.js"></script>

    Invoke the Cookie Manager by calling init() with a config:


    See index.html for more info on configuration

    Any consent requiring services should be set to 'explicit-consent' mode for use with this project.

    Feature: Cookie Banner

    To disable this functionality, set the configuration value of cookie-banner-id to false or remove the definition.

    If you want functionality to display a cookie banner when user preferences have not been set (or expired) then build your cookie banner markup, and give the wrapping element an ID and match it with the configuration value cookie-banner-id.

    This library will automatically bind to the accept and reject buttons nested within the banner element. For matching these buttons to their respective action, both options must be a button element with the data attribute data-cm-action set to accept or reject. This will opt-in or opt-out respectively of any optional cookie categories defined in the configuration. Furthermore, a call will be made to the respective callback (cookie-banner-accept-callback or cookie-banner-reject-callback) if also set in the config.

    <header id="cookie_banner" hidden>
        <h2>Tell us whether you accept cookies</h2>
        <p>We use cookies to collect information about how you use GOV.UK.</p>
        <p>We use this information to make the website work as well as possible and improve government services.</p>
        <div class="govuk-button-group">
            <button data-cm-action="accept">Accept analytics cookies</button>
            <button data-cm-action="reject">Reject analytics cookies</button>
            <a class="govuk-link" href="/">View cookies</a>
        <button data-cm-action="hide">Hide this message</button>

    If the cookie-banner-auto-hide option is set to true, upon clicking either of the accept or reject buttons, the banner will automatically hide itself. If set to false the banner will stay visible, i.e. allowing for a confirmation message that cookie preference has been acknowledged.

    The library can also be binded to a hide/dismiss button for hiding the banner from the user. This button must be a nested element of button within the banner, with the data attribute data-cm-action set to hide.

    Feature: User Preferences Saving

    To disable this functionality, set the configuration value of preference-form-id to false or remove the definition.

    If you want functionality to setup a user preference cookie, then you need to define a HTML form with an ID and match that to the configuration value preference-form-id. Upon initialisation, the library will look for the form when the DOM is ready, and bind to the submit event. When submitted, the library will collect the value of all radio buttons with the checked state. The name of the radio buttons must reflect the category name for cookies defined in your manifest. The values for the radio buttons must be on and off.

    <form id="cm-preference-form">
            <input type="radio" name="analytics" value="on" /> On <br/>
            <input type="radio" name="analytics" value="off" checked /> Off <br/>
            <legend>Application Performance Monitoring:</legend>
            <input type="radio" name="apm" value="on" /> On <br/>
            <input type="radio" name="apm" value="off" checked /> Off <br/>
        <input type="submit" value="Save Preferences"/>


    Configuration is done when calling init() on the Cookie Manager object and is used to determine how you want the Cookie Manager to behave, and defines a manifest of cookies used on your site.

    Using this method, it allows developers to use the native configuration in their application and it should be as simple as serialising the top-level configuration object/array for Cookie Manager to JSON and putting the result into the init() function (either as a variable or directly):

            "delete-undefined-cookies": true,
            "...": "..."

    Configuration Schema

      "delete-undefined-cookies": true,
      "user-preference-cookie-name": "cm-user-preferences",
      "user-preference-cookie-secure": false,
      "user-preference-saved-callback": false,
      "user-preference-cookie-expiry-days": 365,
      "preference-form-id": "cm-preference-form",
      "preference-form-saved-callback" : false,
      "set-checkboxes-in-preference-form": true,
      "cookie-banner-id": "cm-cookie-banner",
      "cookie-banner-visible-on-page-with-preference-form": false,
      "cookie-banner-saved-callback": false,
      "cookie-banner-accept-callback": false,
      "cookie-banner-reject-callback": false,
      "cookie-banner-auto-hide": true,
      "cookie-manifest": [
          "category-name": "essential",
          "optional": false,
          "cookies": [
          "category-name": "analytics",
          "optional": true,
          "cookies": [
          "category-name": "apm",
          "optional": true,
          "cookies": [

    User Preference Settings

    Option Description Default Value
    delete-undefined-cookies Removes any cookies for site that are not defined in the cookie manifest true
    user-preference-cookie-name Name of cookie which stores cookie preferences 'cm-user-preferences'
    user-preference-cookie-secure Sets cookie to include ;secure false
    user-preference-saved-callback Callback function called when user preferences are saved. Calls with object containing consent status. false (no callback function set)
    user-preference-cookie-expiry-days Expiry time of cookie manager preference cookie (in days) 365

    Preference Form Settings

    Option Description Default
    preference-form-id ID attribute on preference form element false
    preference-form-saved-callback Callback function called when user preference form is saved false (no callback function set)
    set-checkboxes-in-preference-form Sets radio buttons in form to be checked based on cookie consent true

    Cookie Banner Settings

    Option Description Default
    cookie-banner-id ID attribute on cookie banner wrapper element false
    cookie-banner-visible-on-page-with-preference-form Should cookie banner also display on page containing preference form true
    cookie-banner-saved-callback Callback function called when cookie banner is saved false (no callback function set)
    cookie-banner-accept-callback Callback function called when cookie banner accept is clicked false (no callback function set)
    cookie-banner-reject-callback Callback function called when cookie banner reject is clicked false (no callback function set)
    cookie-banner-auto-hide Should banner auto-hide after accept or reject is clicked. Disable to allow decision/confirm style banners true

    Cookie Manifest Settings

    Option Description
    category-name Name of the cookie category, i.e analytics
    optional Is cookie category non-essential to site function and can be opted out from
    cookies Array of cookie names included in category


    Unit tests

    The Unit Test will fail if the coverage is below 80%. To run the tests run npm run test or npm run test-html.


    Running npm run test-html will generate a nice html output for the unit tests and coverage in /test and /coverage respectivly.


    Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

    Please make sure to update tests as appropriate.






    npm i @hmcts/cookie-manager

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