FMS 3.5 and Flex 3 – How do I record data over time with NetStream.send()?

After I learned how to work with remote objects, I learned something that I did not know existed. This is the ability to record data over time. This allows us to store user or application actions over time. This data is saved in an flv file on the server thru the NetStream object. Personally, I find this to be very powerfull and can think of several ways of using this. In the meantime, I’ve created a sample application that demonstates how this works in flex.

In fact, it is very similar to the remote objects example, and it starts by running the init function upon creation complete. We then create a NetConnection. Once it is established, we call the openNetstream function that instantiates a NetStream object and assigns it a generic object to store the callback aliases. Once that is all set up the netstream starts to record, the syntax is the same as if we were recording from the webcam.

At this point the stream is recording, you can click on the record button, which does nothing on the UI, but in the backend it is making calls to the sendValues function with the hello world argument. This information is “recorded” and saved into the stream to the flv file on the server. Once you’ve clicked a few times, you can click on the play button. This will load the flv file and play in real time the saved data, which makes calls to the function sendValues which in turn will trace “hello world” as many times as you previously clicked on the record button.

This example is very basic and only works one way, which means you have to start the app again to test it over, but it gives you a good idea on how this works. Check out the send method of the NetStream object in the help files for more ways to work with it. Powerful stuff!

Here is the code:

FMS 3.5 and Flex 3 – How do I use remote shared objects?

As I am learning FMS 3.5, I’ve come across shared objects and wanted to give a working example of it in Flex 3. Client shared objects can be really useful and behave similar to cookies in the browser. Remote shared objects are even more useful because you can share them with other people and call methods on them. Below is a basic example of a remote object working with FMS 3.5, it shows how to set data and call methods on the remote shared object.

The application calls the init() function upon the creation complete event, which creates a Net Connection object that we can work with. Once the connection is established the connectHandler function calls the getSharedObject function where the share object is actually created.

Inside this function the sharedObj is declared and given the name of “so” on the server at the location “nc.uri” which is the net connection address. sharedObjSyncHandler is the function called when there is a sync event on the object, which means when the data of the object changes or when you connect to it etc… The SyncEvent object is what gets returned from this event containing some information. Look up the SyncEvent’s changeList in the help docs for more details. The sharedObj is persistant which means it will remain on the server and is not secure which means the object will not be served over https. This is set with the two last parameters on the getRemote method.

Now that we have an object ready and connected we can do stuff with it. The first thing I tested was to set data in the object. I created two buttons, one that calls the setData function and the other to get the data called getData. Notice that I had to use the setProperty on the object to set the color property in the object. In a real application, I would check to make sure we are connected to the object before trying to write to it by checking for “clear” on the sync handler. After setting the data, you can click on the get data button and see the data traced. Close the application and launch it again, then click the get data button to get the stored data from the server. Because we set the object as persistent, the shared object will remain on the server. It is stored under the application folder and the file extension is fso.

The other functionality of shared objects is the ability to call methods on it. I personally find this pretty powerful for several applications that I will one day share here. But for now, I show how to call a method on my shared object when clicking on the btnCallMethod. So, if you open two browsers with the application, click on the btnCallMethod in one application, you will see the text changing in the other browser. This demonstrates how both clients are sharing the object and update themselves when the data changes. I like it!

CODE:

FMS 3.5 and Flex 3 – How do I load a video in AS3 from FMS?

I’ve started to learn Flash Media Server 3.5 and so far I like it. I got FMS server running and started the tutorials and all is running well. I did have a bit of a hart time to find good examples that intergrated FMS, Flex and AS3. So, I gathered some examples from the docs and http://blog.flexexamples.com. I combined them to create my own class; hopefully this can be helpful to you.

My class extends the UIComponent, and I start by creating a NetConnection. I assign it the client as being “this”, so any callbacks from the server will know where to be directed to. onBWDone() is a callback made by default from FMS and the vod application. I then declare some event listeners as we do not want to go any further if there are issues with our server connection. If I wanted to http stream, I would have passed my connection’s method connect a value of “null”, however, I want to connect to FMS at this point. So, I pass the address of my server.

Now that we have called the server with a netConnection in the constructor, the application waits for a reply from the server. This comes in the form of NetStatusEvent and sent to my netStatusHandler method. The NetStatusEvent contains an info code. From here we know if the connection was successful or not by which code was returned. If the code returned is “NetConnection.Connect.Success” than we can proceed and create the NetStream and the Video object.

In the connectStream() method, I start by declaring an object that will hold the meta data and cuepoints should there be any. This could have been another class, like they did in the docs of Flex. I deciced to go with flexexamples’ way, and I created an object. The next step is to create the netStream, specify its client which is the nsClient object. The last step for the NetStream is to give it the stream name to get off the server.

I then create a video object and attach the stream to it. I decided to apply the smoothing now in case in the future I want to stretch the movie. Finally, I add the movie to the display list. Take note that the ns_onMetaData method is called when the stream gets metadata; this is where I resize the movie based on this information. Below is the complete code.

VideoExample.as:

Now in my MXML, all I have to do is add my tag. I could also declare it in AS3 should I ever want to change it. Depends how it will be implemented I guess.

VideoExample.mxml: