1. 1 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN From CRISTAL to CRISTAL-iSE An overview of the new kernel

2. 2 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Concepts Item – Dynamic object configured at runtime – Object lifecycle driven Agent – Items representing users, other actors Description – Data structure definition – Application logic definition – Stored as data in Items

3. 3 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Item Data Structures Workflow – Lifecycle implementation. Directed acyclic graph of Activities – Sequences data collection & logic Property – Name/Value pairs – Identification and typing information Collection – Type constrained links between Items – Layout or List

4. 4 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Activities Composite (sub-workflow) or Atomic – Active/Inactive – dictates availability – State - User-definable state machine) – Activity properties Activity Properties define – Schema for data collection (Outcome) – Outcome tag/label (Viewpoint) – Application logic to run to complete (Script) – Custom configuration…

5. 5 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Agents and Jobs Agents represent users (human or machine) – Log into CRISTAL-iSE to provide data to Activities and advance the lifecycle – Roles control authorization Job = change of state in an Activity possible by a given Agent right now – Requires work to be done and Outcome generated – Agent can query Item for available Jobs – Certain Roles may push jobs to Agents

6. 6 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Collecting data Agent implementations generate Outcomes – Validated against XML Schema Stored in a database – ClusterStorage interface conveys Item data objects to DB Currently eXist XMLDB Previously Oracle, MySQL, SQLite Custom schema specification – domain specific Query directly on the database

7. 7 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Changing stuff Agents may run Scripts when executing Jobs – Javax.script API Agent processes may not write to DB, only execute Jobs Special activities alongside workflow expose Item modification functions – Alter Collections, Properties – Influence directory entries – Treat this Item as an Item description, and use it to instantiate a new Item!

8. 8 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Changes from 2.2 to 2.4 CRISTAL as a CRISTAL development environment – Activity, Schema, Script Factory Items – Simple Item Description Factory Modules – Single domain extension into multiple modules – Jar containing metafile declaring module contents

9. 9 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Module Contents Name, Namespace (resource reference) - Metadata about the module – Description (verbal), Version – Dependencies (dictates import order) - System properties – Client or Server – Plugin specification - scripts to run on startup/shutdown

10. 10 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Module Contents - Items, Roles and Agents to import/synchronize – : Activities (EA), CompositeActivity (CA), Scripts (SC), Schemas (OD) Single file, specify Version number – : Full Item import (Properties, Collections, Outcomes, Viewpoints) Heavy, for resources implement custom ResourceHandler –,

11. 11 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Kernel 3.0 New Features

12. 12 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN State Machine Definable State Machine, per Activity – Name, ID, proceeds (is terminal) – Name, ID, origin state, terminal state – Outcome required, possible or not allowed – Enabling property Boolean activity property to enable/disable transition

13. 13 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN State Machine Role override – Given Role may execute this transition Reservation modification – Allocates Activity to the performing Agent – Set, Preserve, Clear Values may be explicit, or reference Activity properties ${like this}

14. 14 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Built-in State Machines Composite – Default for sub workflows – Waiting, Started, Finished PredefinedStep – Atomic – 1 State: Available – 1 Transition: Done Default ->

15. 15 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN UUID System Key EntityPath >> ItemPath – Single level string UUID CORBA interfaces use SystemKey (2x64bit int) Globally persistent – Resources and Items should preserve between servers – Optional in kernel & module resources

16. 16 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Lookup & Authenticator LDAP removed from kernel – cristal-ldap module Paths are abstract Lookup & LookupManager Authenticator – Initializes both directory and cluster storage No auth stored in Gateway! – Cleaner multi-user processes

17. 17 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Users, Roles and Jobs Agent now extends Item – Has lifecycle – Predefined steps Password & Role management – Agent descriptions NOT Role, but not quite sure what it is yet. Hierarchical Roles

18. 18 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Client Shell CLI Experimental Javascript client console Modules can contain domain specific function definitions Pluggable authentication

19. 19 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Item Local Object Changes AddC2KObject and RemoveC2KObject are now Admin only – Ordinary scripts must use specific steps to update LocalObjects, which validate input Properties – isMutable property now copied to Property instance – WriteProperty step verifies that property exists and is mutable before it writes.

20. 20 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Item Local Object Changes Collections – Now included in Item.initialize() – API simplified – Collections are now versioned Additional path element for version Current collection named ‘last’ CreateNewCollectionVersion copies the current collection as a numbered snapshot Used during Item instantiation, along with PropertyDescription viewpoint name

21. 21 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Item Local Object Changes Workflow – Abstract properties in ActivityDef Must be overriden by ActivityDefSlot Event – Schema and Viewpoint details Outcome – XPath support for query

22. 22 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Initialization & CreateItem Supply initial Properties, Workflow and Collections – Properties may be overridden (if mutable and declared in PropertyDescription) – Passed as new parameter to CreateItemFromDescription – Collections were originally written outside of initialize() ItemInitialization Event and Outcome stored containing initial properties

23. 23 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN System Properties Built from (in order of precedence): – Module properties – Config file – Connect file – Command-line arguments New ‘ObjectProperties’, allows plugins to be specified by class name or as instance.

24. 24 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Exceptions ClusterStorageException replaced with PersistencyException MembershipException replaced with InvalidCollectionModification exception Better transmission of CORBA exceptions to client processes

25. 25 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Predefined Steps Big overhaul of PredefinedSteps – New in 3.0: AddNewCollectionDescription, CreateNewCollectionVersion – Agent container: SetAgentPassword, SetAgentRoles, CreateAgentFromDescription, RemoveAgent – Server container: – Directory context management – Role management

26. 26 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Predefined Steps Modified steps – CreateItemFromDescription Description version Initial properties (PropertyArrayList) – AddMemberToCollection Supply additional slot properties – AddNewSlot Reference description version Richer exception set

27. 27 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Future Improved model semantics in collections – Item > Item Description – ActivityDef > Schema, Script and StateMachine Properties still supported, but deprecated and migrated automatically – CompositeActivityDef > ActivityDef Enhanced security – Auth tokens for server communications – Per-item read permissions (in Lookup) – SSL

28. 28 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN Future Use-case Items – Model Agents and their interactions with the system – Executable model: self-documenting development – Captures test data, supplying automatic Agent input simulation for testing Much more: – Non-layout composite ‘Activity Bags’, BPMN2.0 features, Do/Loop workflow construct, ViewpointDescriptions, Automatic property population, client-side composite activities

29. 29 Andrew Branson - CRISTAL OSS Launch 15 th October 2014 - CERN END