# Storage Manager

The aim of this guide is to show how to setup correctly your storage configuration for common usages of the editor and explain also some additional advanced settings

# Basic configuration

The storage manager is a built-in module implemented inside GrapesJS which allows the persistence of your data. By default, GrapesJS saves the data locally by using the built-in LocalStorage which just leverages localStorage API. You can initialize the editor with different storage configurations via storageManager option:

const editor = grapesjs.init({
  ...
  // Default configurations
  storageManager: {
    id: 'gjs-',             // Prefix identifier that will be used on parameters
    type: 'local',          // Type of the storage
    autosave: true,         // Store data automatically
    autoload: true,         // Autoload stored data on init
    stepsBeforeSave: 1,     // If autosave enabled, indicates how many changes are necessary before store method is triggered
  },
});

The id option is used to prevent collisions (quite common with localStorage) in case of multiple editors on the same page, therefore you will see parameters passed like { 'gjs-components': '...', 'gjs-style': '...', }

If you need to disable the storage manager you can pass any empty type:

...
storageManager: { type: null },

For all other available options check directly the configuration source file.

# Setup remote storage

Switching up the remote storage is very simple, it's just a matter of specifying your endpoints for storing and loading, which generally might be also the same (if you rely on HTTP methods).

const editor = grapesjs.init({
  ...
  storageManager: {
    type: 'remote',
    stepsBeforeSave: 3,
    urlStore: 'http://endpoint/store-template/some-id-123',
    urlLoad: 'http://endpoint/load-template/some-id-123',
    // For custom parameters/headers on requests
    params: { _some_token: '....' },
    headers: { Authorization: 'Basic ...' },
  }
});

As you can see we've left some default option unchanged, increased changes necessary for autosave triggering and passed remote endpoints.

# Store and load templates

Even without a fully working endpoint, you can see what is sent from the editor by triggering the store and looking in the network panel of the inspector. GrapesJS sends mainly 4 types of parameters and it prefixes them with the gjs- key (you can disable it via storageManager.id). From the parameters, you will get the final result in 'gjs-html' and 'gjs-css' and this is what actually your end-users will gonna see on the final template/page. The other two, 'gjs-components' and 'gjs-style', are a JSON representation of your template and therefore those should be used for the template editing. So be careful, GrapesJS is able to start from any HTML/CSS but use this approach only for importing already existent HTML templates, once the user starts editing, rely always on JSON objects because the HTML doesn't contain information about your components. You can achieve it in a pretty straightforward way and if you load your page by server-side you don't even need to load asynchronously your data (so you can turn off the autoload).

// Lets say, for instance, you start with your already defined HTML template and you'd like to
// import it on fly for the user
const LandingPage = {
  html: `<div>...</div>`,
  css: null,
  components: null,
  style: null,
};
// ...
const editor = grapesjs.init({
  ...
  // The `components` accepts HTML string or a JSON of components
  // Here, at first, we check and use components if are already defined, otherwise
  // the HTML string gonna be used
  components: LandingPage.components || LandingPage.html,
  // We might want to make the same check for styles
  style: LandingPage.style || LandingPage.css,
  // As we already initialize the editor with the template we can skip the `autoload`
  storageManager: {
    ...
    autoload: false,
  },
});

If for any reason you need to get the data from the remote storage you can trigger the load, at any time, manually

editor.load(res => console.log('Load callback'));

Similarly, you have the same control over the storing. By default, the autosave is enabled and is triggered by how many changes are made to the template (change it via stepsBeforeSave option). As before, you can disable this behavior and trigger it manually when you need it

...
const editor = grapesjs.init({
  ...
  storageManager: {
    ...
    autosave: false,
  },
});
// Call load somewhere
editor.store(res => console.log('Store callback'));

If you need to check changes which yet need to be stored you can use editor.getDirtyCount(). At any, successful, store of the editor, it resets the count.

# Setup the server

Server configuration might differ for any use case so generally, it's something up to you on how to make it work, but usually, the flow is pretty straightforward. Create two endpoints, one for storing (eg. mydomain.com/store-page/123) and the other one for loading (eg. mydomain.com/load-page/123), you can also create just one and distinguish them via HTTP methods (eg. mydomain.com/page/123, via GET you load the template, with POST you store it). When you store, the editor doesn't expect any particular result but only a valid response from the server (status code 200). When you load the template, return a JSON object with the data you have (don't forget to include the id prefix if it's used)

{
  // `gjs-` is the id prefix
  'gjs-components': [{ tagName: 'div', ... }, {...}, ...],
  'gjs-style': [{...}, {...}, ...],
}

Be sure to have a correct Content-Type response header, eg. in PHP you would do something like this:

header('Content-Type: application/json');
echo json_encode([
  'gjs-components': [...],
  'gjs-style': [...],
]);

# Storage API

The Storage module has also its own set of API that allows you to extend and add new functionalities.

# Define new storage

One of the most useful methods of API is the possibility to add new storages. You might think, we have the local and remote storages, what else do we need, right? Well, let's take as an example the local one. As you already know, it relies on localStorage API which is really cool and easy to use but one of his specs might be a big limit, by default it has a limited amount of MB to use per site (something around 5MB-10MB, depends on the browser implementation). As an alternative, we can make use of IndexedDB which is also quite well supported and allows more space usage (each browser implements its own rules, for a better understanding on how browser storage limits work, check here). IndexedDB configuration might be too much verbose for this guide so we decided to create the grapesjs-indexeddb plugin, so you can check its source and see how it's implemented. For this guide we gonna see something more simpler but with the same flow, it'll be just a simple javascript object which stores key-value data, not persistent at all but the concept is the same.

const editor = grapesjs.init({
  ...
  storageManager: { type: 'simple-storage' },
});

// Here our `simple-storage` implementation
const SimpleStorage = {};

editor.StorageManager.add('simple-storage', {
  /**
   * Load the data
   * @param  {Array} keys Array containing values to load, eg, ['gjs-components', 'gjs-style', ...]
   * @param  {Function} clb Callback function to call when the load is ended
   * @param  {Function} clbErr Callback function to call in case of errors
   */
  load(keys, clb, clbErr) {
    const result = {};

    keys.forEach(key => {
      const value = SimpleStorage[key];
      if (value) {
        result[key] = value;
      }
    });

    // Might be called inside some async method
    clb(result);
  },

  /**
   * Store the data
   * @param  {Object} data Data object to store
   * @param  {Function} clb Callback function to call when the load is ended
   * @param  {Function} clbErr Callback function to call in case of errors
   */
  store(data, clb, clbErr) {
    for (let key in data) {
      SimpleStorage[key] = data[key];
    }
    // Might be called inside some async method
    clb();
  }
});

# Extend storage

Among other needs, you might need to use existing storages to create more complex uses. For example, let's say we would like to mix the local and remote storages inside another one. This is how it would look like:

const sm = editor.StorageManager;

sm.add('local-remote', {
  store(data, clb, clbErr) {
    const remote = sm.get('remote');
    const local = sm.get('local');
    // ...
    remote.store(data, clb, err => {
      // eg. some error on remote side, store it locally
      local.store(data, clb, clbError);
    });
  },

  load(keys, clb, clbErr) {
    // ...
  },
});

If you need to completely replace the storage, just use the same id in add method

editor.StorageManager.add('local', {
  // New logic for the local storage
  load() {
    // ...
  },

  store() {
    // ...
  },
});

# Examples

Here you can find some of the plugins extending the Storage Manager

• grapesjs-indexeddb - Storage wrapper for IndexedDB
• grapesjs-firestore - Storage wrapper for Cloud Firestore

# Events

Another way to extend storage capabilities is to make use of GrapesJS's event hooks, you can check here the list of all available events for the Storage module. Let's see some of the cases where you might want to use them:

• Loading animation on storage requests

editor.on('storage:start', startLoading);
editor.on('storage:end', endLoading);

• Error handling

editor.on('storage:error', (err) => {
    alert(`Error: ${err}`);
});

• Extend parameters to store

editor.on('storage:start:store', (objectToStore) => {
    if (needToAddExtraParam) {
      objectToStore.customHtml = `<div>...${editor.getHtml()}...</div>`;
    }
});

• Do stuff post load

editor.on('storage:end:load', (resultObject) => {
    if (resultObject.hasSomeKey) {
      // do stuff
    }
});