Category: Wowza Media Server

Information , specification , modules and setup on Wowza media Server

Wowza REST APIs and HTTP Providers

This article show the different ways to make calls to Wowza Media Engine from external applications and environments for various purposes  such as getting server status , listeners , connections , applications and its streams etc .

HTTP Providers

HTTP Providers are Java classes that are configured on a per-virtual host basis.

Some pre packaged HTTP providers that return data in XML  :

1. HTTPConnectionCountsXML

Returns connection information like Vhost , application , application instance , message in bytes rate , message out byte rates etc.

http://%5Bwowza-ip-address%5D:8086/connectioncounts

Screenshot from 2015-11-24 20:23:51

2. HTTPConnectionInfo
Returns detailed connection information such as

http://%5Bwowza-ip-address%5D:8086/connectioninfo

server=1

3. HTTPServerVersion

Returns the Wowza Media Server version and build number. It’s the default HTTP Provider on port 1935.

url : http://%5Bwowza-ip-address%5D:1935

Wowza Streaming Engine 4 Monthly Edition 4.1.1 build13180

4. HTTPLiveStreamRecord

gets the web interface to record online streams

url : http://%5Bwowza-ip-address%5D:8086/livestreamrecord

Screenshot from 2015-11-24 20:22:16

5. HTTPServerInfoXML

Returns server and connection information

url :http://%5Bwowza-ip-address%5D:8086/serverinfo

Screenshot from 2015-11-24 20:34:08

6. HTTPClientAccessPolicy .

It is used for fetching the Microsoft Silverlight clientaccesspolicy.xml from the conf folder.

7. HTTPCrossdomain

To get the Adobe Flash crossdomain.xml file from [install-dir]/conf folder.

8.HTTPProviderMediaList

Dynamic method for generating adaptive bitrate manifests and playlists from SMIL data.

9.HTTPStreamManager

The Stream Manager returns all applications and their stream in web interface.

url http://%5Bwowza-ip-address%5D:8086/streammanager).

Screenshot from 2015-11-24 20:38:32

10 .HTTPTranscoderThumbnail

Returns a bitmap image from the source stream being transcoded.

url: http://%5Bwowza-ip-address%5D:8086/transcoderthumbnail?application=%5Bapplication-name%5D&streamname=%5Bstream-name%5D&format=%5Bjpeg or png]&size=[widthxheight]

Each HTTP provider can be configured with different request filter and authentication method ( none , basic , digest).  We can even create our own substitutes for the HTTP providers as defined in the next section .

Extending HTTProvider2Base

The following code snippet describes the process of creating a Wowza Web services that return a json containing all the values .

Imports to build a HTTP provider


import com.wowza.wms.application.*;
import com.wowza.wms.vhost.*;
import com.wowza.wms.http.*;
import com.wowza.wms.httpstreamer.model.*;

//since we want to return in json format

import org.json.simple.JSONObject;

The class declaration is as folllows


public class DCWS extends HTTProvider2Base
{

....

}

The code to extract application names


public JSONObject listChannels(){

JSONObject obj=new JSONObject();

//get params from virtual host and iterate through it
List<String> vhostNames = VHostSingleton.getVHostNames();
Iterator<String> iter = vhostNames.iterator();
while (iter.hasNext())
{
String vhostName = iter.next();
IVHost vhost = (IVHost)VHostSingleton.getInstance(vhostName);
List<String> appNames = vhost.getApplicationNames();
Iterator<String> appNameIterator = appNames.iterator();

int i=0;
while (appNameIterator.hasNext())
{
String applicationName = appNameIterator.next();

try {
String key = "channel"+ (++i);
obj.put(key, URLEncoder.encode(applicationName, "UTF-8"));
}

catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
return obj;
}

The code which responds to HTTP request

TBD..

Ref :

Wowza Secure URL params Authentication for streams in an application

To secure the publishers for a common application through username -password specific for stream names , this post is useful . It  uses Module Core Security to prompt back the user for supplying credentials.

The detailed code to check the rtmp query-string for parameters  and performs the checks –  is user is allowed to connect and is user allowed to stream on given stream name is given below .

Initialize the hashmap containing publisher clients and IapplicationInstance

HashMap <Integer, String> publisherClients =null;
IApplicationInstance appInstance = null;

On app start initilaize the IapplicationInstance object .

public void onAppStart(IApplicationInstance appInstance)
{
    this.appInstance = appInstance;
}

Onconnect is called called when any publisher tries to connects with media server. At this event collect the username and clientId from the client.
Check if publisherclient contains the userName which client has provided else reject the connection .

public void onConnect(IClient client, RequestFunction function, AMFDataList params)
{

AMFDataObj obj = params.getObject(2);
AMFData data = obj.get("app");

if(data.toString().contains("?")){

   String[] paramlist = data.toString().split();
   String[] userParam = paramlist[1].split("=");
   String userName = userParam[1];

   if(this.publisherClients==null){
       this.publisherClients = new HashMap<Integer, String>();
}

if(this.publisherClients.get(client.getClientId())==null){
    this.publisherClients.put(client.getClientId(),userName);
} else {
    client.rejectConnection();
}
}
}

AMFDataItem: class for marshalling data between Wowza Pro server and Flash client.

As the event user starts to publish a stream after sucessful connection Onpublishing function is called . It extracts the stream name from the client ( function extractStreamName() )and checks if user is allowed to stream on the given streamname (function isStreamNotAllowed()) .

public void publish(IClient client, RequestFunction function, AMFDataList params)
{
String streamName = extractStreamName(client, function, params);
if (isStreamNotAllowed(client, streamName))
{
sendClientOnStatusError(client, NetStream.Publish.Denied, "Stream name not allowed for the logged in user: "+streamName);
client.rejectConnection();
}
else{
invokePrevious(client, function, params);
}

}

Function when publisher disconnects from server . It removes the client from publisherClients.

public void onDisconnect(IClient client)
{
if(this.publisherClients!=null){
this.publisherClients.remove(client.getClientId());
}
}

The function to extract a streamname is


public String extractStreamName(IClient client, RequestFunction function, AMFDataList params)
{
String streamName = params.getString(PARAM1);
if (streamName != null)
{
String streamExt = MediaStream.BASE_STREAM_EXT;

String[] streamDecode = ModuleUtils.decodeStreamExtension(streamName, streamExt);
streamName = streamDecode[0];
streamExt = streamDecode[1];
}

return streamName;
}

The fucntion to check if streamname is allowed for the given user


public boolean isStreamNotAllowed(IClient client, String streamName)
{
WMSProperties localWMSProperties = client.getAppInstance().getProperties();
String allowedStreamName = localWMSProperties.getPropertyStr(this.publisherClients.get(client.getClientId()));
String sName="";
if(streamName.contains("?"))
sName = streamName.substring(0, streamName.lastIndexOf(&amp;amp;quot;?&amp;amp;quot;));
else
sName = streamName;
return !sName.toLowerCase().equals(allowedStreamName.toLowerCase().toString()) ;
}

On adding the application to wowza server make sure that the ModuleCoreSecurity is present under Modules in Application.xml

<Module>
<Name>ModuleCoreSecurity</Name>
<Description>Core Security Module for Applications</Description>
<Class>com.wowza.wms.security.ModuleCoreSecurity</Class>
</Module>






Also ensure that property securityPublishRequirePassword is present under properties




<Property>
<Name>securityPublishRequirePassword</Name>
<Value>true</Value>
<Type>Boolean</Type>
</Property>





Add the user credentials as properties too. For example to give access to testuser with password 123456 to stream on myStream include the following ,




<Property>
<Name>testUser</Name>
<Value>myStream</Value>
<Type>String</Type>
</Property>





Also include the mapping of user and password inside of conf/publish.password file





# Publish password file (format [username][space][password])
# username password





testuser 123456