Red5 with Spring MVC

Access Red5 context in spring MVC DispatcherServlet

Before we start, some prerequisites for reader.

How Spring MVC works. tutorial
Basic knowledge about red5.

Then only you can understand clearly 😄 . If you don't have, no worries. Having knowledge in core java and servlet is enough

Day by day I experienced in Red5. I will explain a useful enhancement about red5. Let's start...

Red5 is an open source flash media server. If your webapplication is in the same server you can build some interesting streaming apps by binding your webapp and red5app. But you can not use red5 as a web application server, because by default RTMPServlet support macromedia-fcs (application/x-fcs) content type not http. But Internally Red5 uses Tomcat and Spring. By simple tweaks you can add http support for your red5 application.

So I add my own Red5DispatcherServlet in red5app web.xml to handle http request.

add this in your web.xml

<servlet>
  <servlet-name>red5Demo-web</servlet-name>
  <servlet-class>com.demo.web.servlet.Red5DispatcherServlet</servlet-class>
  <init-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/red5Demo-dispatcher-servlet.xml</param-value>
  </init-param>
</servlet>

All configurations files in https://github.com/arulrajnet/red5Demo/tree/master/java/webapp/WEB-INF

You can use the default spring mvc DispatcherServlet. But problem is you can't access the red5 context from your controller. It means all objects loaded by red5 ContextLoggingListener can't be accessble from your web context. Did you understand...?

ok. Usually spring DispatcherServlet creates one web context and sets parents as ApplicationContext loaded by spring mvc ContextLoaderListener. Did you notice in red5app web.xml file we are using red5 own context loader listener. So if you use Spring mvc DispatcherServlet there is no parent context.

To override this we have to set red5 ApplicationContext as DispatcherServlet parent context. For that only I have some customization

Red5DispatcherServlet.java

package com.demo.web.servlet;

import org.red5.logging.Red5LoggerFactory;
import org.slf4j.Logger;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.servlet.DispatcherServlet;

public class Red5DispatcherServlet extends DispatcherServlet {

  private static final long serialVersionUID = 1L;

  private static final Logger LOG = Red5LoggerFactory.getLogger(Red5DispatcherServlet.class, "red5Demo");

  private WebApplicationContext parentContext;

  @Override
  protected WebApplicationContext initWebApplicationContext() {
    WebApplicationContext wac = null;
    parentContext = WebApplicationContextUtils.getWebApplicationContext(getServletContext());
    if (parentContext == null) {
      parentContext = (WebApplicationContext)
      getServletContext().getAttribute(
      WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);
    }
    if (parentContext == null) {
      LOG.error("No web application context found.");
    } else {
      wac = createWebApplicationContext(parentContext);
    }

    setDetectAllHandlerAdapters(Boolean.TRUE);
    setDetectAllHandlerMappings(Boolean.TRUE);
    setDetectAllHandlerExceptionResolvers(Boolean.TRUE);
    setDetectAllViewResolvers(Boolean.TRUE);

    onRefresh(wac);

    String attrName = getServletContextAttributeName();
    getServletContext().setAttribute(attrName, wac);
    if (this.logger.isDebugEnabled()) {
      this.logger.debug("Published WebApplicationContext of servlet '" + getServletName() + "' as ServletContext attribute with name [" + attrName + "]");
    }

    return wac;
  }

  public WebApplicationContext getParentContext() {
    return parentContext;
  }

  public void setParentContext(WebApplicationContext parentContext) {
    this.parentContext = parentContext;
  }
}

Then define your handlers and view resolvers in red5Demo-dispatcher-servlet.xml

I have created one demo application for red5 with spring mvc. please refer github red5Demo https://github.com/arulrajnet/red5Demo

To Download this code

Install Git then run the below command.

git clone [email protected]:arulrajnet/red5Demo.git

I will write a separate post for setup red5 development environment and how to build that app.