Client side cache. Wrapper around indexedDB !!! Don't try to refactor this code - starting of transaction in separate promise is not work for Firefox!!! see this topic

Contain functions for simple key/value manipulations and advanced (entity related) manipulations.

Create separate database for each connection inside application.

For every database will create three store

  • permanent for data persistent between sessions and
  • session for data, live inside user session only (from login to login)
  • user for custom data

  
      var c = await new UBCache('mydb').createStorage();
c.put([
  {key: 'note1', value: {prop1: 1, prop2: 'do something'} },
  {key: 'note2', value: 'do something else'}
]).then();
c.get('note1').then(UB.logDebug); //output result to console
c.clear();
c.get('note1').then(function(value){
  console.log(value === undefined ? 'all cleared': 'hm... something wrong')
})

# new UBCache (dbName:  string, versionopt:  number)

Arguments:
  • dbName: string

    Name of indexedDB database we create. Usually this is UBConnection#baseURL. Constructor lower case dbName during creation

  • version: number

    Optionally database version

Members

# cacheTypes static

Possible cache types for business logic data

Name Type Description
None string No cache performed
Entity string Client validate data version on server for each request
Session string First request to data in the current session ALWAYS retrieve data from server. All other requests got a local copy
SessionEntity string Client validate data version on server ONLY for first request in the current session

# PERMANENT : string static

PERMANENT store name

# SESSION : string static

SESSION store name

# dbName instance

Name Type Description
dbName string

name of indexedDB database

Methods

# clear (storeNameopt:  string) → Promise instance

Removes all data from the store

Arguments:
  • storeName: string

    default to 'userData'

# createStorage () → Promise.<UBCache> instance

If indexedDB is available and access to it is allowed - open an indexed DB, otherwise - fallback UBCache to use in-memory storage.

MUST be called and awaited before any get/put operations

# get (key:  string, storeNameopt:  string) → Promise instance

Retrieve data from store by key. If key not found - resolve result to undefined

Return:

resolved to key value.

Arguments:

# getAllKeys (storeNameopt:  string) → Promise instance

Retrieves all values from store. This is slow operation - try to avoid it

Return:

resolved to Array of store keys

Arguments:
  • storeName: string

    default to 'userData'

# put (data:  Object | Array.<{key: string, value}>, storeNameopt:  string) → Promise instance

Put one or several values to store (in single transaction). Modifies existing values or inserts as new value if nonexistent.

If value === undefined we put null instead, to understand in future get this is null value or key not exist

Arguments:

# remove (key:  string | Array.<string> | RegExp, storeNameopt:  string) → Promise instance

Remove data from store.

  • If key is String - we delete one key;
  • If key is Array - we delete all keys in array;

Arguments:
  
      //remove data with key = 'key1' from userData store
$App.cache.remove('key1').then();

//remove 2 rows: with key = 'key1' and 'key2'  from session store
$App.cache.remove(['key1', 'key2'], UBCache.SESSION).then();

# removeIfMach (regExp:  RegExp, storeNameopt:  string) → Promise instance

Remove data from store where keys match regExp. Internally use UBCache#getAllKeys so is slow. Better to use remove([key1, ..keyN])

Arguments:
  
      console.time('removeIfMach')
$App.cache.removeIfMach(/^admin:ru:cdn_/, 'permanent').then(function() {
   console.timeEnd('removeIfMach');
})