Daniel R.

Rough draft of notes

Peter Farland is talking about Configuring, Debugging and Deploying LiveCycle Data Services.

Notes from the talk will also be posted to his blog.

Version issues with LCDS

A LCDS version is best used with the version of the Flex SDK that comes with it, in most

Flex 2.0.1/FDS 2.0.1
Flex 2.0.1 HF2/LCDS 2.5
Flex 2.0.1 HF3/LCDS 2.5.1
Flex 3/LCDS 2.5.1

Client side: rpc.swc and fds.swc and services-config.xml are the key pieces to keep synchronized. Don't forget fds_rb.swc.

If you find a bug open up the swc and look in catalog.xml to report the version you are using. The jar file has a similar version in the manifest.

Performance very tied to java version. 1.5.0_07 is very bad for performance. Avoid 1.4.2_02 to 1.4.2_05 and 1.4.2_10. 1.5.0_13 is recommended.

Configuration

Flex compiler knows about services-config.xml. -services compiler flag generates needed AS3 code. -services isn't needed if you want to roll your own ChannelSet management code.

Multiple Channels in a ChannelSet provides failover.
Use a single ChannelSet for all services in the client.
Only authenticate once per client ChannelSet.setCredentials().
Allows runtime determination of secure channel selection.

Programmatically create the ChannelSet to provide a poor man's load balancing. Randomize the order that the Channels are defined is. Still give you fail-over but the random list gives some load balancing (Math.random()).

LCDS messages brokers can create MessageDestinations on start programmatically instead of having to specify everything in a services-config.xml.
Important to optimize your configuration file and get rid of sample pieces and channels that are not used. Can improve compiler performance since it is less data to parse and manipulate. Be sure to remove debugging and redployer watchers from a production configuration file.
Sun's JDK XML parser should be replaced by xalan.jar.

Flex Builder only supports one project in memory at a time. Only the last edited project is retained in memory for incremental builds.

When debugging make sure you have references to data types retrieved from runtime otherwise they won't be linked in. Missing flash.utils.IExternalizable leads to "one of the parameters is incorrect" error which can be solved by referencing the class.

Client side debugging: will dump additional information to flashlog.txt. Paros Proxy, Charles, ServiceCapture are great client side traffic sniffers.

Server side debugging: Can configure debugging levels in services-config.xml. LCDS includes a server side tool sniffer.exe.

Common browser issue is non 200 HTTP status codes.

When doing deployment compile your SWF and simplify your web.xml file. LCDS 2.5.1 allows configuring client point to be secure while server uses HTTP to allow using SSL accelerators. RTMP can use the bind-address and bind-port to allow hooking it up to a load balancer. Resource availability can be problematic on hosted web servers since most are tuned for short lived connections on persistent connections that LCDS uses.

With LCDS express (limited to 1 CPU) 1000 plus users with RTMP should be possible since it is multiple threaded. Other techniques like servlets would block too many threads.