topic Re: Displaying uploaded content from a portlet in Alfresco Archive

Displaying uploaded content from a portlet

rsfeir — Wed, 16 Nov 2005 17:47:04 GMT

Hi,We're evaluating Alfresco, love the ease of installation and the UI is very clear and usable.The one thing that was not immediately obvious is how to perhaps implement the follow usecase:We have a portal, JBoss Portal, and in this portal we have content. Right now the content sits in plain html

Re: Displaying uploaded content from a portlet

gavinc — Thu, 17 Nov 2005 10:36:51 GMT

Hi,

Yes, there is a way to do this with Alfresco but not out of the box, you will need to do some customization.

We have a servlet that can display content. You could create a separate portlet that just consists of an iframe and make the source of the iframe the URL to the download servlet.

To get the URL you can either use the helper method on the sevlet if you have the Node object to hand…

DownloadContentServlet.generateBrowserURL(node.getNodeRef(), node.getName());‍

…or you could find out the id of the content you want to show and build up the URL manually. An example of the URL you'll need have a look at the "View in Browser" link in the document details screen.

Hope that helps.

Re: Displaying uploaded content from a portlet

rsfeir — Thu, 17 Nov 2005 15:21:21 GMT

Excellent thanks for the prompt reply, this is the answer. I think my approach will be to front your servlet with a portlet, don't really want to use an iFrame, and then pass to the portlet via a request parameter the page I want to see. This simplifies a lot of things for us thanks.

R

Re: Displaying uploaded content from a portlet

rsfeir — Mon, 21 Nov 2005 23:18:14 GMT

Hi,

I wrote a simple portlet to try to prove the concept that things will work well, but I've hit a snag and I can't seem to find a way around it.

I've chosen, for reason of simplicity, to go with building the URL for the portlet like the one we see on the preview page. With that I've written the following sample code:

public class CMSViewPortlet extends GenericPortlet {
     @Override
    protected void doView(RenderRequest renderRequest, RenderResponse renderResponse)
            throws PortletException, PortletSecurityException, IOException {

        //Set the required content type. We're expecting to render text/html in this case.
        renderResponse.setContentType("text/html");
        //setup the request dispatcher and pass it the URL init parameter value found in portlet.xml
        final URL url = new URL(getPortletConfig().getInitParameter("url"));
        final BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
        final PrintWriter out = renderResponse.getWriter();
        while(in.readLine() != null) {
            out.append(in.readLine());
        }
        in.close();
        out.close();

    }
}

Well I definitely get information back from Alfresco, the problem is that I get the login page, not the content. So the content is protected, which is fine in some cases, but we need to have the content be public and not have anyone need to log in to see this particular content we're working on.

Further if there is protected content, how do we get around having users sign in to our portal and yours?

I'm using a base jboss portal install with our own theme, so I'm not doing anything way out of the ordinary.

Any clues and help would be greatly appreciated.

Thanks
R

Re: Displaying uploaded content from a portlet

rdanner — Mon, 21 Nov 2005 23:34:38 GMT

Hi,

I wrote a simple portlet to try to prove the concept that things will work well, but I've hit a snag and I can't seem to find a way around it.

I've chosen, for reason of simplicity, to go with building the URL for the portlet like the one we see on the preview page. With that I've written the following sample code:

public class CMSViewPortlet extends GenericPortlet {
     @Override
    protected void doView(RenderRequest renderRequest, RenderResponse renderResponse)
            throws PortletException, PortletSecurityException, IOException {

        //Set the required content type. We're expecting to render text/html in this case.
        renderResponse.setContentType("text/html");
        //setup the request dispatcher and pass it the URL init parameter value found in portlet.xml
        final URL url = new URL(getPortletConfig().getInitParameter("url"));
        final BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
        final PrintWriter out = renderResponse.getWriter();
        while(in.readLine() != null) {
            out.append(in.readLine());
        }
        in.close();
        out.close();

    }
}

Well I definitely get information back from Alfresco, the problem is that I get the login page, not the content. So the content is protected, which is fine in some cases, but we need to have the content be public and not have anyone need to log in to see this particular content we're working on.

Further if there is protected content, how do we get around having users sign in to our portal and yours?

I'm using a base jboss portal install with our own theme, so I'm not doing anything way out of the ordinary.

Any clues and help would be greatly appreciated.

Thanks
R

MM….
you are tying to use a feature alfresco supports for content preview which is only available if you are logged in.

If you access alfresco through the web service, jcr, or repository api you wont hit this snag because you will need to pass authentication.

using the JCR mechanism will take you the most miles because it is a standard not an implementation. (not that you would ever want to, but you could switch to jackrabbit or some other system in the future.) I am sure alfresco will rule the universe in the future… so this may not be a concern

There are examples that ship with alfresco that can put you on the road to jcr glory.

give me some time over this holiday and I will share some of the toys i am building.

Re: Displaying uploaded content from a portlet

rsfeir — Tue, 22 Nov 2005 00:35:19 GMT

Excellent thanks.

I can handle either webservice or JCR, but since I'm new I didn't realize all this was already there.

I'd still like to see the toys you're working on.

thanks for the prompt reponse!

R

Re: Displaying uploaded content from a portlet

gavinc — Tue, 22 Nov 2005 09:49:17 GMT

Hi,

As Russ says you could go the JCR or webservice route if you want. Alternatively if you want to continue the route you are going you can just append a ticket parameter to the URL (this does mean though your user would have to be logged in).

In the logged in session you can retrieve the ticket (it's stored in a session variable called '_alfAuthTicket') and add it as a paramter to the URL you pass to the servlet.

Hope this helps,

Re: Displaying uploaded content from a portlet

rsfeir — Tue, 22 Nov 2005 15:06:18 GMT

I was trying to use commons-http to create a client to authenticate, but so far I'm missing something because it's not authenticating right. I've got all 3 fields which look to be required, and pulled the name of the fields from the form.

That said, we're going to see today and discuss which avenue to take. Personally I'd rather not keep going down this path, it's just 'ugly', and given the alternatives this path, at least in my opinion, shouldn't even be considered.

I'm leaning towards WS right now, but we'll see. I'll keep you guys posted and thanks for the continued support.

R

Re: Displaying uploaded content from a portlet

rsfeir — Tue, 22 Nov 2005 18:55:15 GMT

Ok, I looked at the examples and that lead me to a couple of questions. The example for JCR seems to presume that I am running this test in the same webapp since it's looking for the spring app context definition files in the classpath.

Our setup would be such that the webapps may or may not be on the same machine, or even same server container. So Alfresco would be in one location and the jboss portal in another.

Given that possiblity, do I still use the JCR API? From what I can tell right now, we'd need to run the portal and Alfresco integrated in the same web app to use the JCR because I don't see a way to get at the Repository object remotely (I'm still reading about JCR).

Any direction you can point me in would be extremely helpful.

Thanks
R

Re: Displaying uploaded content from a portlet

rdanner — Tue, 22 Nov 2005 19:39:54 GMT

Ok, I looked at the examples and that lead me to a couple of questions. The example for JCR seems to presume that I am running this test in the same webapp since it's looking for the spring app context definition files in the classpath.

Our setup would be such that the webapps may or may not be on the same machine, or even same server container. So Alfresco would be in one location and the jboss portal in another.

Given that possiblity, do I still use the JCR API? From what I can tell right now, we'd need to run the portal and Alfresco integrated in the same web app to use the JCR because I don't see a way to get at the Repository object remotely (I'm still reading about JCR).

Any direction you can point me in would be extremely helpful.

Thanks
R

This is a good and pretty common question. The JCR is just an API and doesnÃ¢â‚¬â„¢t really address geography. Therefore, you might have an implementation that is based on a local repository, one backed up by web services or RMI. You might also have a hybrid approach of backing the system up by a local repository and integrating it with the master.

In terms of continuity… I have been thinking about this problem. I donÃ¢â‚¬â„¢t want my site to be dependant on a remote CMS system. I want it to use it when it is there and continue to function when it is not. There are many ways to skin this cat but one approach that will kill it is to back the app up with a direct remote connection to the repository (unless you plan on consuming cached content when the CMS is down.)

Re: Displaying uploaded content from a portlet

rsfeir — Tue, 22 Nov 2005 19:46:11 GMT

Ok so in our case it sounds like we should be using a webservice. The repository availability is something we need to look at, and if the repo is not available, I have no issue consuming cached content, but if the repository is not available and we use WS, even cached content won't be there if we only have one cms install.

I'm getting a much clearer idea about all this, and your support and response speed and clarity of answers has been truly amazing.

Thanks
R

Re: Displaying uploaded content from a portlet

rsfeir — Tue, 22 Nov 2005 20:12:22 GMT

Ok one final question before I drive down the WS road. Is it possible, both License wise and integration wise, to take your war file and somehow drop it into the jboss deploy directory, or perhaps the protal sar directory and have your classes be part of the same classloader the jboss portal runs on?

The reason I ask is because if I can have Alfreco exist in the same classloader, then it would be very easy for us to use the JCR solution.

One way I thought of doing this, and this is where the licensing issue may arise, is to simply explode your war file, and merge its contents with our own portal code, then the whole thing will load in the same classloader and we're good to go. However, this will also cause a headache down the line since everytime we want to update, we'd have to merge your new code with what we have, and that's not soemthing we want to do.

So I'm hoping there is a little trick there which might make it do the magic we need. If not the WebService solution is certainly great and will do the trick very nicely.

Thanks again.
R

Re: Displaying uploaded content from a portlet

rdanner — Tue, 22 Nov 2005 21:12:39 GMT

I dont follow. I may simply be missing something. Alfresco implements the JCR. It has it's own impl alfresco.jcr.repository.RepositoryImpl.

I dont understand what difference it will make if alfresco is in the same class loader unless some configuration behind the JBoss porlet is set to load the alfresco implementation.

Also if JBoss has functionality that relies on the level II of the JCR then you wont be able to plug alfresco in to that space. Alfresco V1.0 doesn't support level II.

My oganization will need level II functionality and we are looking at what we need and how much distance exists between what alfresco currently provides and what we need. Some functionality may exist in the nightly builds (as level II support is underway in the nightly builds)