Psli / FCUUID

iOS UUID / Universally Unique Identifiers library as alternative to UDID and identifierForVendor.

FCUUID

iOS UUID library as alternative to the old good UDID and identifierForVendor.
This library provides the simplest API to obtain universally unique identifiers with different persistency levels.

It's possible to retrieve the UUIDs created for all devices of the same user, in this way with a little bit of server-side help it's possible manage guest accounts across multiple devices easily.

##Requirements & dependencies

• iOS >= 5.0
• ARC enabled
• Key-value storage enabled (target / Capabilities / iCloud / Key-value storage)
• Security.framework
• UICKeyChainStore
• (optional) - KeyChain sharing enabled (entitlements and provisioning profile) if you need to share the same uuidForDevice / uuidsOfUserDevices values accross multiple apps with the same bundle seed.

##Installation

####CocoaPods: pod 'FCUUID'

####Manual install:

• Copy FCUUID.h and FCUUID.m to your project.
• Manual install UICKeyChainStore

##Usage setup It is recommended to do the setup in applicationDidFinishLaunchingWithOptions method.

• Add an observer to the FCUUIDsOfUserDevicesDidChangeNotification to be notified about uuids of user devices changes.
• If necessary, migrate from a previously used UUID or UDID using one of the migrations methods listed in the API section (it's recommended to do migration before calling uuidForDevice or uuidsForUserDevices methods). Keep in mind that migration works only if the existing value is a valid uuid and uuidForDevice has not been created yet.
• Call any class method to enforce iCloud sync.

##API Get different UUIDs (each one with its own persistency level)

//changes each time (no persistent)
+(NSString *)uuid;

//changes each time (no persistent), but allows to keep in memory more temporary uuids
+(NSString *)uuidForKey:(id<NSCopying>)key;

//changes each time the app gets launched (persistent to session)
+(NSString *)uuidForSession;

//changes each time the app gets installed (persistent to installation)
+(NSString *)uuidForInstallation;

//changes each time all the apps of the same vendor are uninstalled (this works exactly as identifierForVendor)
+(NSString *)uuidForVendor;

//changes only on system reset, this is the best replacement to the good old udid (persistent to device)
+(NSString *)uuidForDevice;

Get the list of UUIDs of user devices

//returns the list of all uuidForDevice of the same user, in this way it's possible manage guest accounts across multiple devices easily
+(NSArray *)uuidsOfUserDevices;

Migrate from a previously stored UUID / UDID
Before migrating an existing value it's recommended to debug it by simply passing commitMigration:NO and logging the returned value.
When you will be ready for committing the migration, use commitMigration:YES.
After the migration, any future call to uuidForDevice will return the migrated value.

//these methods search for an existing UUID / UDID stored in the KeyChain or in UserDefaults for the given key / service / access-group
+(NSString *)uuidForDeviceMigratingValueForKey:(NSString *)key commitMigration:(BOOL)commitMigration;
+(NSString *)uuidForDeviceMigratingValueForKey:(NSString *)key service:(NSString *)service commitMigration:(BOOL)commitMigration;
+(NSString *)uuidForDeviceMigratingValueForKey:(NSString *)key service:(NSString *)service accessGroup:(NSString *)accessGroup commitMigration:(BOOL)commitMigration;

Check if value is a valid UUID

+(BOOL)uuidValueIsValid:(NSString *)uuidValue;

Enjoy :)