Flash Storage
There are times where you need to store user related variables in some kind of permanent storage then relocate the user into another section of your application, be able to retrieve the data, use it and then clean it. All of these tedious operations are definitely doable but why reinvent the wheel if we can have the platform give us a tool for maintaing conversation variables across requests. The key point for Flash RAM is where will the data be stored so that it is unique per user. ColdFusion gives us several persistent scopes that we can use and we have also created several flash storages for this purpose. Since the ColdBox flash scope is based on an interface, the flash scope storage can be virtually anywhere. You will find all of these implementations in the following package: coldbox.system.web.flash. In order to choose what implementation to use in your application you need to tell the ColdBox.cfc which one to use via flash configuration structure:
// flash scope configurationflash = {scope = "session,client,cluster,cache,or full path",properties = {}, // constructor properties for the flash scope implementationinflateToRC = true, // automatically inflate flash data into the RC scopeinflateToPRC = false, // automatically inflate flash data into the PRC scopeautoPurge = true, // automatically purge flash data for youautoSave = true // automatically save flash scopes at end of a request and on relocations.};
Below is a nice chart of all the keys in this configuration structure so you can alter behavior of the Flash RAM objects:
Key | Type | Required | Default | Description |
scope | string or instantiation path | false | session | Determines what scope to use for Flash RAM. The available aliases are: session, client, cluster, cache or a custom instantiation path |
properties | struct | false | {} | Properties that can be used inside the constructor of any Flash RAM implementation |
inflateToRC | boolean | false | true | Whatever variables you put into the Flash RAM, they will also be inflated or copied into the request collection for you automatically. |
inflateToPRC | boolean | false | false | Whatever variables you put into the Flash RAM, they will also be inflated or copied into the private request collection for you automatically |
autoPurge | boolean | false | true | This is what makes the Flash RAM work, it cleans itself for you. Be careful when setting this to false as it then becomes your job to do the cleaning |
autoSave | boolean | false | true | The Flash RAM saves itself at the end of requests and on relocations via setNextEvent(). If you do not want auto-saving, then turn it off and make sure you save manually |
The included flash implementations for ColdBox are:
Name | Class | Description |
Session | coldbox.system.web.flash.SessionFlash | Persists variables in session scope |
Cluster | coldbox.system.web.flash.ClusterFlash | Persists variables in cluster scope via Railo only |
Client | coldbox.system.web.flash.ClientFlash | Persists variables in client scope |
Mock | coldbox.system.web.flash.MockFlash | Mocks the storage of Flashed variables. Great for unit/integration testing. |
Cache | coldbox.system.web.flash.ColdboxCacheFlash | Persists variables in the ColdBox Cache |
Each RAM implementation can also use properties in order to alter its behavior upon construction via the properties configuration struct. Below are the properties our core implementations can use:
Session Flash Settings
none
Cluster Flash Settings
none
Client Flash Settings
none
Mock Flash Settings
none
Cache Flash Settings
cacheName: The cache provider name declared in CacheBox
// flash scope configurationflash = {scope = "cache",properties = { cacheName="cluster" }};