Table of content

• Installation
• Demo
• Getting Started
• Simple Example
• Example With SerializableProperties
• Example With All Options
• Global Configuration
• API
  • makePersistable
  • StorageOptions & ReactionOptions
  • isHydrated
  • isPersisting
  • pausePersisting
  • startPersisting
  • stopPersisting
  • hydrateStore
  • clearPersistedStore
  • getPersistedStore
  • PersistStoreMap
• Links

Installation

# by yarn
yarn add mobx-persist-store

# OR by npm
npm i mobx-persist-store

Demo

Mobx Persist Store with MobX 6

Getting Started

makePersistable(this, { name: 'SampleStore', properties: ['someProperty'], storage: window.localStorage });

To simply persist your MobX store use makePersistable. Pass a reference of the store (this) as the first argument. The second argument is the StorageOptions for persisting the store data. In the example below name, properties, and storage properties are required but if you use configurePersistable you can set a global storage adapter, so you only have to set it once. You can also pass a third argument (ReactionOptions) to control when data should be saved.

Hydration of the store will happen automatically when makePersistable is created.

Simple Example

import { makeAutoObservable } from 'mobx';
import { makePersistable } from 'mobx-persist-store';

export class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this);

    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'], storage: window.localStorage });
  }
}

Example With SerializableProperties

import { makeAutoObservable } from 'mobx';
import { makePersistable } from 'mobx-persist-store';

export class SampleStore {
  someProperty: ['a', 'b', 'c'];

  constructor() {
    makeAutoObservable(this);

    makePersistable(this, {
      name: 'SampleStore',
      properties: [
        {
          key: 'someProperty',
          serialize: (value) => {
            return value.join(',');
          },
          deserialize: (value) => {
            return value.split(',');
          },
        },
      ],
      storage: window.localStorage,
    });
  }
}

Example With All Options

import { makePersistable } from 'mobx-persist-store';
import localForage from "localforage";

...
makePersistable(
  this,
  {
    name: 'SampleStore',
    properties: ['someProperty'],
    storage: localForage,  // localForage, window.localStorage, AsyncStorage all have the same interface
    expireIn: 86400000, // One day in milliseconds
    removeOnExpiration: true,
    stringify: false,
    debugMode: true,
  },
  { delay: 200, fireImmediately: false },
);
...

Global Configuration

If you plan on using the same values for some options you can set them globally with the configurePersistable.

import { configurePersistable } from 'mobx-persist-store';

// All properties are optional
configurePersistable(
  {
    storage: window.localStorage,
    expireIn: 86400000,
    removeOnExpiration: true,
    stringify: false,
    debugMode: true,
  },
  { delay: 200, fireImmediately: false }
);

export class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this);

    // Now makePersistable only needs `name` and `properties`:
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }
}

configurePersistable sets items globally, but you can override them within makePersistable.

API

You should only need makePersistable but this library also provides other utils for more advance usage.

makePersistable (Promise)

makePersistable sets up store persisting.

import { makeAutoObservable } from 'mobx';
import { makePersistable } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this);

    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }
}

makePersistable is a Promise, so you can determine when the store has been initially hydrated. Also, you can use isHydrated to determine the hydration state.

import { makeAutoObservable, action } from 'mobx';
import { makePersistable } from 'mobx-persist-store';
...
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] }).then(
      action((persistStore) => {
        console.log(persistStore.isHydrated);
      })
    );
...

StorageOptions & ReactionOptions

StorageOptions

• name (String) - Should be a unique identifier and will be used as the key for the data storage.
• properties (Array of String) - A list of observable properties on the store you want to persist. Doesn't save MobX actions or computed values.
• storage (localStorage Like API) - Facilitates the reading, writing, and removal of the persisted store data. For ReactNative it may be AsyncStorage, FS, etc. and for React - localStorage, sessionStorage, localForage etc.
  • If you have an app that is Server-side rendering (SSR) you can set the value undefined to prevent errors.
• expireIn (Number) - A value in milliseconds to determine when the data in storage should not be retrieved by getItem. Never expires by default.
• removeOnExpiration (Boolean) - If expireIn has a value and has expired, the data in storage will be removed automatically when getItem is called. The default value is true.
• stringify (Boolean) - When true the data will be JSON.stringify before being passed to setItem. The default value is true.
• debugMode (Boolean) - When true a console.info will be called for several of mobx-persist-store items. The default value is false.

ReactionOptions MobX Reactions Options

• delay (Number) - Allows you to set a delay option to limit the amount of times the write function is called. No delay by default.
  • For example if you have a 200 millisecond delay and two changes happen within the delay time then the write function is only called once. If you have no delay then the write function would be called twice.
• fireImmediately (Boolean) - Determines if the store data should immediately be persisted or wait until a property in store changes. false by default.

configurePersistable(
  {
    storage: window.localStorage,
    expireIn: 86400000,
    removeOnExpiration: true,
    stringify: false,
    debugMode: true,
  },
  { delay: 200, fireImmediately: false }
);
...
makePersistable(
  this,
  {
    name: 'SampleStore',
    properties: ['someProperty'],
    storage: window.localStorage,
    expireIn: 86400000,
    removeOnExpiration: true,
    stringify: false,
    debugMode: true,
  },
  { delay: 200, fireImmediately: false }
);

isHydrated

isHydrated will be true once the store has finished being updated with the persisted data.

import { makeAutoObservable } from 'mobx';
import { makePersistable, isHydrated } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  get isHydrated() {
    return isHydrated(this);
  }
}

isPersisting

isPersisting determines if the store is being currently persisted. When calling pausePersisting the value will be false and true with startPersisting is called.

import { makeAutoObservable } from 'mobx';
import { makePersistable, isPersisting } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  get isPersisting() {
    return isPersisting(this);
  }
}

pausePersisting

pausePersisting pauses the store from persisting data.

import { makeAutoObservable } from 'mobx';
import { makePersistable, pausePersisting } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  pauseStore() {
    pausePersisting(this);
  }
}

startPersisting

startPersisting starts persisting the store data again after pausePersisting was called.

import { makeAutoObservable } from 'mobx';
import { makePersistable, startPersisting } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  startStore() {
    startPersisting(this);
  }
}

stopPersisting

stopPersisting calls pausePersisting and internally removes reference to the store. You should only call this function if you have store(s) that are re-created or do not live for the entire life of your application.

import { makeAutoObservable } from 'mobx';
import { makePersistable, stopPersisting } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  stopStore() {
    stopPersisting(this);
  }
}

This function prevents memory leaks when you have store(s) that are removed or re-crated. In the React example below stopPersisting is called when the component is unmounted.

import React, { useEffect, useState } from 'react';
import { observer } from 'mobx-react-lite';
import { stopPersisting } from 'mobx-persist-store';

export const SamplePage = observer(() => {
  const [localStore] = useState(() => new SampleStore());

  useEffect(() => {
    // Called when the component is unmounted
    return () => localStore.stopStore();
  }, []);

  return (
    <div>
      {localStore.someProperty.map((item) => (
        <div key={item.name}>{item.name}</div>
      ))}
    </div>
  );
});

hydrateStore (Promise)

hydrateStore will update the store with the persisted data. This will happen automatically with the initial makePersistable call. This function is provide to manually hydrate the store. You should not have to call it unless you are doing something that modified the persisted data outside the store.

import { makeAutoObservable } from 'mobx';
import { makePersistable, hydrateStore } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  async hydrateStore() {
    await hydrateStore(this);
  }
}

clearPersistedStore (Promise)

clearPersistedStore will remove the persisted data. This function is provide to manually clear the store's persisted data.

import { makeAutoObservable } from 'mobx';
import { makePersistable, clearPersistedStore } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  async clearStoredDate() {
    await clearPersistedStore(this);
  }
}

getPersistedStore (Promise)

getPersistedStore will get the persisted data. This function is provide to manually get the store's persisted data.

import { makeAutoObservable } from 'mobx';
import { makePersistable, getPersistedStore } from 'mobx-persist-store';

class SampleStore {
  someProperty: [];

  constructor() {
    makeAutoObservable(this, {}, { autoBind: true });
    makePersistable(this, { name: 'SampleStore', properties: ['someProperty'] });
  }

  async getStoredData() {
    return getPersistedStore(this);
  }
}

PersistStoreMap

PersistStoreMap is a JavaScript Map object where the key is a reference to the store, and the value is a reference to the persist store. Note: calling stopPersisting(this) will remove the store and persist store references from PersistStoreMap to prevent memory leaks.

import { PersistStoreMap } from 'mobx-persist-store';

Array.from(PersistStoreMap.values()).map((persistStore) => persistStore.getPersistedStore());

Links

• MobX Site