ngrx-store-localstorage
Simple syncing between ngrx store and local or session storage.
Dependencies
ngrx-store-localstorage
depends on @ngrx/store and Angular 2+.
Usage
npm install ngrx-store-localstorage --save
- Wrap localStorageSync in an exported function.
- Include in your meta-reducers array in
StoreModule.forRoot
.
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { StoreModule, ActionReducerMap, ActionReducer, MetaReducer } from '@ngrx/store';
import { localStorageSync } from 'ngrx-store-localstorage';
import { reducers } from './reducers';
const reducers: ActionReducerMap<IState> = {todos, visibilityFilter};
export function localStorageSyncReducer(reducer: ActionReducer<any>): ActionReducer<any> {
return localStorageSync({keys: ['todos']})(reducer);
}
const metaReducers: Array<MetaReducer<any, any>> = [localStorageSyncReducer];
@NgModule({
imports: [
BrowserModule,
StoreModule.forRoot(
reducers,
{metaReducers}
)
]
})
export class MyAppModule {}
API
localStorageSync(config: LocalStorageConfig): Reducer
Provide state (reducer) keys to sync with local storage. Returns a meta-reducer.
Arguments
config
An object that matches with theLocalStorageConfig
interface,keys
is the only required property.
LocalStorageConfig
An interface defining the configuration attributes to bootstrap localStorageSync
. The following are properties which compose LocalStorageConfig
:
-
keys
(required) State keys to sync with local storage. The keys can be defined in two different formats:-
string[]
: Array of strings representing the state (reducer) keys. Full state will be synced (e.g.localStorageSync({keys: ['todos']})
). -
object[]
: Array of objects where for each object the key represents the state key and the value represents custom serialize/deserialize options. This can be one of the following:-
An array of properties which should be synced. This allows for the partial state sync (e.g.
localStorageSync({keys: [{todos: ['name', 'status'] }, ... ]})
). -
A reviver function as specified in the JSON.parse documentation.
-
An object with properties that specify one or more of the following:
-
serialize
: A function that takes a state object and returns a plain json object to pass to json.stringify. -
deserialize
: A function that takes that takes the raw JSON from JSON.parse and builds a state object. -
replacer
: A replacer function as specified in the JSON.stringify documentation. -
space
: The space value to pass JSON.stringify. -
reviver
: A reviver function as specified in the JSON.parse documentation. -
filter
: An array of properties which should be synced (same format as the stand-alone array specified above). -
encrypt
: A function that takes a state string and returns an encrypted version of that string. e.g.(state: string) => btoa(state)
-
decrypt
: A function that takes a state string and returns a decrypted version of that string. e.g.(state: string) => atob(state)
-
-
-
-
rehydrate
(optional)boolean
: Pull initial state from local storage on startup, this will default tofalse
. -
storage
(optional)Storage
: Specify an object that conforms to the Web Storage API interface to use, this will default tolocalStorage
. -
removeOnUndefined
(optional)boolean
: Specify if the state is removed from the storage when the new value is undefined, this will default tofalse
. -
storageKeySerializer
(optional)(key: string) => string
: Custom serialize function for storage keys, used to avoid Storage conflicts. -
restoreDates
(boolean? = true): Restore serialized date objects. If you work directly with ISO date strings, set this option tofalse
. -
syncCondition
(optional)(state) => boolean
: When set, sync to storage medium will only occur when this function returns a true boolean. Example:(state) => state.config.syncToStorage
will check the state tree under config.syncToStorage and if true, it will sync to the storage. If undefined or false it will not sync to storage. Often useful for "remember me" options in login. -
checkStorageAvailability
(boolean? = false): Specify if the storage availability checking is expected, i.e. for server side rendering / Universal. -
mergeReducer
(optional)(state: any, rehydratedState: any, action: any) => any
: Defines the reducer to use to merge the rehydrated state from storage with the state from the ngrx store. If unspecified, defaults to performing a full deepmerge on anINIT_ACTION
or anUPDATE_ACTION
.
Usage
Key Prefix
localStorageSync({
keys: ['todos', 'visibilityFilter'],
storageKeySerializer: (key) => `cool_${key}`,
});
In above example Storage
will use keys cool_todos
and cool_visibilityFilter
keys to store todos
and visibilityFilter
slices of state). The key itself is used by default - (key) => key
.
Target Depth Configuration
localStorageSync({
keys: [
{ feature1: [{ slice11: ['slice11_1'], slice14: ['slice14_2'] }] },
{ feature2: ['slice21'] }
],
});
In this example, feature1.slice11.slice11_1
, feature1.slice14.slice14_2
, and feature2.slice21
will be synced to localStorage.feature1
and localStorage.feature2
.
Known Workarounds
Release Notes / Changelog
From version 10 onwards, check GitHub Releases for release notes. For older versions check the CHANGELOG.md.
Contributing
See CONTRIBUTING.md for instructions on how to contribute.