Server-Side ActionScript Language Reference — Client class

JOdy

In ActionScript 2, you define the functions directly on the NetConnection object, like this:

nc = new NetConnection();
nc.onBWDone = function(){
    return true;
};
nc.onBWCheck = function(){
   return 0;
};
nc.connect("rtmp:/clientCall");

In ActionScript 3, you define the functions on an object assigned to the NetConnection.client property, like this:

var clientObj:Object = new Object();
clientObj.onBWDone = onBWDone;
clientObj.onBWCheck = onBWCheck;
nc.client = clientObj;

public function onBWDone(... rest):Boolean {
   return true;
}

public function onBWCheck(... rest):Number {
   return 0;
}

Note:The previous code includes the callback functions expected by the FMS “live” and “vod” applications.

The NetStream class works similarly to the NetConnection class. You can call NetStream.send() to send messages to other connected clients. Those clients need callback functions that handle the messages.

In AS2 you can define functions on a NetStream object and in AS3 you define functions on an object assigned to the NetStream.client property. See NetStream.client and NetStream.send().

There are several ways to handle callback methods–you can use the technique in this post, you can assign the client property to a new class, you can extend the NetStream or NetConnection class, or you can assign the client property to this. For good examples, see “Writing callback methods for metadata and cue points”.

All clients in the mesh must make a connection to Stratus (a hosted service available on Adobe Labs), but the data shared in the mesh doesn’t go through Stratus, it travels directly between the peers in the group. Stratus is a non-commercial server that lets Adobe preview technologies that will become available in future releases of Flash Media Server.  You can also use LiveCycle Collaboration Service to build commercial P2P apps. LCCS rolls the P2P functionality for you and falls back to hub and spoke if needed. Tom Krcha has a nice explanation of the difference between Stratus and LCCS.

The classes you need to build P2P apps are documented in the beta version of the unified ActionScript 3.0 Reference. (Yes, this means that from now on there will be one and only one version of the AS3R. No more special versions for Flex, AIR, etc etc. Get all your Flash Platform API information from a single source. Phew.) Where was I? Right… P2p…

• Use the GroupSpecifier class to define a group and its options. This class creates the groupspec string which is the immutable identity of the group.
• Use the NetGroup class to manage a group and get statistics about a group.
• Use the NetStream class to multicast audio, video, and data. Just like you do with hub and spoke apps.
• Use the NetConnection class to connect to Stratus (and in the future, FMS). For P2P apps, use the RTMFP protocol.

I’ll be writing more about P2P Flash apps (here and for the Adobe docs), but meanwhile, check out Tom’s MAX 2009 session.

I’ll be at MAX in Los Angeles next week. The schedule has lots of great sessions about video, FMS, and Peer-to-peer networking. I’ll be TA’ing the lab “Building a Scalable Interactive Video Solution Using P2P in Flash Builder” — if you’re signed up, find me . I think all (most?) sessions will be broadcast on AdobeTV within a few days after MAX and the keynotes will be streamed live, lemme see if I can find the info… That was easy: http://max.adobe.com/online/.

Enjoy!
Jody

• Cookbooks
• Adobe Help Client

The Cookbooks are live on adobe.com and the Help client is on labs.adobe.com and works with labs versions of Flash Builder and Flash Catalyst. Try them out and send Adobe your feedback — it’s always appreciated.

By default, when Flash Player connects to FMS, it scans the following ports in order: 1935, 443, 80, 80 (RTMP tunneling). To configure a secure port for an adaptor, specify a minus sign in front of the port number in the ADAPTOR.HOSTPORT parameter in the RootInstallationFolder/conf/fms.ini file, as follows:

ADAPTOR.HOSTPORT = :1935,-443

With this config, when Flash Player uses an RTMPS string to connect to FMS it uses port 443. FMS also returns data over port 443. To tell a Flash Player client to make an SSL connection to Flash Media Server, use an RTMPS string (”rtmps://domain/applicationname”) in the NetConnection.connect() call.   Any traffic with an RTMP string (”rtmp://domain/applicationname”) uses port 1935.

In other words, to configure SSL, you need to specify that a port is “secure” by specifying a minus sign in front of the port number in the fms.ini file. Then you specify an SSL connection by using the “rtmps” protocol specifier in the connection URI. If no port is specified, the default port for RTMPS is 443. If you configure any port other than 443 as secure, for example, -1935, you need to explicitly specify the port in the URI, for example, “rtmps://domain:1935/applicationname”.

Configure the hardware to listen externally on port 443 and forward unencrypted data to FMS on port 1935.

If you’re using hardware SSL, you don’t need to complete the configuration steps necessary for using native SSL, the hardware does all the hard work and simply forwards unencrypted RTMP to FMS.

Actually, the DVR functionality is built into FMS 3.5. To publish a DVR stream, just record or append the stream as you publish it–NetStream.publish(”myvideo”, “record”) or NetStream.publish(”myvideo”, “append”). To view a DVR stream, use NetStream.play(”myvideo”, 0, -1). The “0″ indicates that you want to play a recorded stream. When you play a live stream that’s being recorded, you’re really watching the recorded stream a hair behind.

Before DVRCast was released, you couldn’t record media captured with Flash Media Live Encoder 3.0. To create a DVR stream (one that viewers can pause, rewind, etc.), you have to record the stream. (OK, the server records the stream, but you tell the server to do it.) DVRCast lets you record media that you capture with FMLE 3.0 and FMLE 3.0 encodes media with better codecs than Flash Player. Ergo, DVRCast is good.

To build a client app that connects to the DVRCast app, you can use the FLVPlayback 2.5 component. (Both Flash and Flex support FLVPlayback 2.5.)  Download FLVPlayback 2.5 from the Flash Media Server Tools page as well. A new version (2.5.0.15) was released with the DVRCast app so you may need to upgrade. Oh, and the FLVPlayback 2.5 component also supports dynamic streaming.

For more information, see Kevin Towes’ blog.

<NetworkingIPv6 enable="true" />

When IPv6 is enabled, if an IPv4 client connects, it has an IPv4 connection. If an IPv6 client connects, it has an IPv6 connection. The server listens for IPv4 and IPv6 addresses. You can see these connections in the server logs. To see an example in an edge log, see Configure IPv6 in the Flash Media Server docs.

Remember, you also have to configure the OS networking stack to support IPv6 and activate IPv6 on the nic– see the OS docs for instructions. Also, to use a numeric IPv6 address in a client-side script, server-side script, or in the server configuration files, enclose the address in brackets:

rtmp://[fd5e:624b:4c18:ffff:0:5efe:10.133.128.108]:1935/streamtest

For link-local addresses, specify the interface zone index:

rtmp://[fe80::204:23ff:fe14:da1c%4]:1935/streamtest