Reliable asynchronous web-services with Apache CXF

Transcription

1 Reliable asynchronous web-services with Apache CXF Florent Benoit, BULL/OW2 ] Guy Vachet, France Telecom [guy.vachet@orange-ftgroup.com] New CXF transport allowing reliable Web Services based on JMS transport and JTA transaction. # 1

2 Context / History # 2

3 France Telecom Orange context Large heterogeneous IS Over 3000 interconnected applications Since 2006, generalized web services usage with SOAP over HTTP, in order to: standardize exchanges between applications create facades between the front end and the legacy back-office SOAP over HTTP drawbacks Tightly-coupled transport Services inaccessible when the provider is inactive Difficulty to analyze failures (404-type errors) Long-lasting back office operations unadapted to real-time front-end interactions: we need asynchronism! # 3

4 Objectives SOAP over JMS proposal Real asynchronous client-server exchange Guarantee the reliability of message delivery (no message loss, no duplicate) JTA Transactional features client-side: between its resources and the message sent server-side: between message reading and its resources similarly for responses Technical context WSDL first Based on CXF2.1 Standard Java EE context: JOnAS (Java EE) and JORAM (JMS) # 4

5 Limitations of the async. CXF proposal Current proposal on Apache side for asynchronous transport seems to present some limitations: One thread per request scalability? Memory-based mechanism recovery after crash? No transaction support message sending/receiving Our objective: define an alternative solution respecting our objectives and context to be integrated smoothly in CXF # 5

6 A new proposal # 6

7 Content of the new Proposal Based on Apache CXF Use benefits of EJB Message Driven Bean instead of simple «JMS Message Listener» JTA Transaction support (Java EE standard) Use of a pool of objects for handling requests New CXF Transport: named MDB (url = mdb://) Based on some parts of the CXF/JMS library (used for some functions like building a JMS message from a CXF message) 3 parts Client: sending and receiving Server: endpoint # 7

8 Global architecture view # 8

9 Handling errors [1/2] # 9

10 Handling errors [2/2] If there is a failure when a Message Driven Bean is handling a JMS message, new attempts to redeliver the message will occur (one retry for each failure as per JMS specification) For each failure: Transaction rollback All database operations (or involving other XA resources) are canceled Upon reaching a specified number of repetitive failures: Sending the fault message to a «Dead Message Queue» JMS Persistent messages When we restart servers, all persisted messages will be delivered No message loss # 10

11 Prerequisites Java EE server: (Tested with JOnAS M3) Java EE 5 application server with EJB 3.1 Singleton bean support Java EE 6 App server JMS server (Tested with JOnAS/JORAM) Spring is used for the Transport configuration Spring already used by CXF # 11

12 Availability [1/2] Code hosted on OW2 JOnAS forge JOnAS subproject: Own life-cycle following CXF releases Module available through the OW2 maven repository (and Maven Central repository) Metrics 2 interfaces (AsyncHandler and ContextInfo) 10 new classes 1500 Lines of code (without examples / tests) # 12

13 Easy to plug: Availability [2/2] Add a new MDB CXF transport = Adding MDB transport jar as library in the class-path Integrated with: CXF 2.2.x (2.2.11) CXF 2.3.x (2.3.0) Available by default on JOnAS application server (nothing to do) JOnAS M4 SNAPSHOT Wish to contribute back this transport to the Apache CXF community # 13

14 Demo # 14

15 Demo use-case [1/2] # 15

16 Demo use-case [2/2] One server with JMS JOnAS hosting all JMS Queues («endpoint» queue and «client answer» queue JMS server used is JORAM 3 JOnAS servers JOnAS 1: Sending messages from a client JOnAS 2: WS Endpoint JOnAS 3: Handling response on the client side Crash recovery demo for servers JOnAS2 and JOnAS3 # 16

17 Conclusion # 17

18 Conclusion France Telecom Orange started to use this transport. Some projects are experimenting this. Global idea is to contribute back this MDB protocol to Apache CXF community Available on # 18

19 Q & A Florent Benoit, BULL/OW2 ] Guy Vachet, France Telecom # 19