Using presentation window for cobrowsing alternatives

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DJP

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Apr 15, 2010, 4:36:21 PM4/15/10
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Hello,

 

I made few test and I tried to share using presentation window an url. Here’s the result with www.bigbluebutton.org on the enclosed file.

 

In the presentation window, you have 2 new fields : one input texte for an url (ie. www.bigbluebutton.org) and a “GO” button. When click, the server retrieve the webpage, convert it to PDF, and show in presentation window.

 

Is it interesting ?

Another addition to this can be made to that to support “distant” presentation file …

 

What do you guys think ?

 

Cya,

DJP

PS: As you can see, it’s not perfect since menu at top is screwed, but everylink weblink on page is clickable…

 

 

 

ae6a959381c7cd05667a35f2ec0c13af.png

Asterisk-Tux

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Apr 15, 2010, 4:42:48 PM4/15/10
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Hi DJP:

Good idea!!. The URLs used in presentations very common and have this
functionality is a good contribution, BBB is a good tool and something
I want to rescue is the very good information that give from the
website.

Thk
Martin Rodriguez
VoIP Engineer


On 15 abr, 17:36, "DJP" <D...@architectes.org> wrote:
> Hello,
>
> I made few test and I tried to share using presentation window an url.

> Here's the result withwww.bigbluebutton.orgon the enclosed file.


>
> In the presentation window, you have 2 new fields : one input texte for an

> url (ie.www.bigbluebutton.org) and a "GO" button. When click, the server


> retrieve the webpage, convert it to PDF, and show in presentation window.
>
> Is it interesting ?
>
> Another addition to this can be made to that to support "distant"

> presentation file .


>
> What do you guys think ?
>
> Cya,
>
> DJP
>
> PS: As you can see, it's not perfect since menu at top is screwed, but

> everylink weblink on page is clickable.
>
>  ae6a959381c7cd05667a35f2ec0c13af.png
> 305 KVerDescargar

Richard Alam

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Apr 15, 2010, 4:43:54 PM4/15/10
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Will the links being clicked display on the presentation window as PDF too?

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Denis Zgonjanin

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Apr 15, 2010, 5:07:27 PM4/15/10
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That's a great idea! It has a certain simplicity and elegance to it. 

How does the server convert the page to pfd? Is there an html to pdf converter?

Denis Zgonjanin

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Apr 15, 2010, 5:16:15 PM4/15/10
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And you know, this gets around all the issues about crossscripting etc.. Since the presenter isn't actually browsing using their browser, we don't have to worry about all that stuff. They can click links and that can take everyone to another page, but they can't enter text fields for credentials so they can't log in anywhere, and no script is executed. And everyone always sees the same page.
Obviously there are limitations, but they're the same limitations as other co-browsing implementations have. Except this one has less side-effects and works w/o plugins, iframes, etc.

DJP

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Apr 15, 2010, 5:20:47 PM4/15/10
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Currently, no, but I haven't checked this out yet. Perhaps we can hook or
modify something in pdf2swf so when clicked, an event is catched by Flash
client that can proceed (only for presenter) the next url...

For now, link are open in a new browser page.

DJP

> -----Message d'origine-----
> De : bigblueb...@googlegroups.com [mailto:bigbluebutton-
> d...@googlegroups.com] De la part de Richard Alam
> Envoyé : jeudi 15 avril 2010 22:44
> À : bigblueb...@googlegroups.com
> Objet : Re: [bigbluebutton-dev] Using presentation window for
> cobrowsing alternatives

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DJP

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Apr 15, 2010, 5:31:07 PM4/15/10
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You’re absolutely right, I didn’t even thought about all that stuff, just making test to see if we can do something !

 

I used wkhtmltopdf (http://code.google.com/p/wkhtmltopdf/) for html -> pdf converter. I used the binary, and I already made the java converter class + beans, etc… I just need to properly handle this new url field. For now (shame on me…!!), I select a “.weblink” file on my file system, such as www.bigbluebutton.org.weblink (lol!), and click upload, and the presentation converter handle everything, using actual conversion mechanism (doc-convertion.xml + Weblink2PDFService + …). I just made a FileUploadWindow preview to see what can it gives in the UI.

 

This tool, wkhtml2pdf, is really really great : it use webkit rendering engine (which is a good one !) and convert the page to PDF. It’s really efficient, I used it by the past in a project and worked very well.

 

You should try it out, just d/l binary, and try few webpages, you’ll see, it’s really good ;-)

 

Denis, since you worked on presentation whiteboard/link handling, do you think it’s possible to catch click event on link and change behavior so Flash client ask Tomcat to convert the clicked url page ?

 

DJP

De : bigblueb...@googlegroups.com [mailto:bigblueb...@googlegroups.com] De la part de Denis Zgonjanin
Envoyé : jeudi 15 avril 2010 23:16


À : bigblueb...@googlegroups.com
Objet : Re: [bigbluebutton-dev] Using presentation window for cobrowsing alternatives

 

And you know, this gets around all the issues about crossscripting etc.. Since the presenter isn't actually browsing using their browser, we don't have to worry about all that stuff. They can click links and that can take everyone to another page, but they can't enter text fields for credentials so they can't log in anywhere, and no script is executed. And everyone always sees the same page.

Denis Zgonjanin

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Apr 15, 2010, 8:40:08 PM4/15/10
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That's very interesting, wkhtmltopdf.

I think yes, it's possible to get the link events and send them to the server. However there are some issues with this we have to think about. Right now people can click on links in the presentation and a new window will open. With cobrowsing, the presentation thinks the webpage is just another presentation page. So we need a way to distinguish when clicking on  link will open in a new window vs when it should use co-browsing. Also some differences in this behavior for presenters/viewers. But these are mostly UI issues and can be solved.

I will look into how to intercept link click events in the next few days and let you know what I come up with.

Denis

Jeremy Thomerson

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Apr 16, 2010, 1:06:57 AM4/16/10
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I think this is certainly a nifty implementation - and a totally new idea from anything that we have previously discussed.  However, is it really of practical use?  When I think of any situation that I want to use co-browsing in, I can only think of situations that will require more complex actions than clicking simple http links.  Typically, if I were using cobrowsing, I am going to be demoing some functionality of some web application.  This will likely include submitting forms, as well as AJAX interaction with many apps today.  

I don't want to be labelled a pessimist - I certainly think this is something that can be accomplished  But, I think that it still presents quite a challenge.  

Have we considered making it an applet?  This could perhaps work if there was a way that we created an applet window that opened and used Webkit (or some other) rendering engine.  Since we are basically creating a very simple browser, it would have full control over the DOM in the page, and could relay DOM events to the other participants via Red5.  Of course, making it an applet means that it works like desksharing - requiring a download - and this would require it even for the participants.  So, it would likely need to be an "add-on" feature that wasn't enabled by default.  Just an idea, though.

Jeremy

Jeremy Thomerson

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Apr 16, 2010, 1:17:44 AM4/16/10
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I forgot to include this link: http://www.concord.org/~dmarkman/jws/webkit/

Although it didn't launch on this Ubuntu machine that I'm on, it appears to be based on the idea I was suggesting - a Java browser wrapped around a webkit rendering engine.  I'm not sure if this could run as an applet with the additional restrictions that applets have, but perhaps it could.

Jeremy

DJP

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Apr 16, 2010, 4:38:20 AM4/16/10
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Hi Jeremy,

 

Doesn’t work on Windows either, it’s specific to MacOS ;-)

 

I think you misunderstood my proposal : It’s not clearly the right way to do co-browsing,  and as I said, it’s an alternative. I mean, it’s clearly not cobrowsing but I think it might be interesting for many users. Plus, you can imagine by that way to have a default welcome string, branded in HTML by the user or BBB, to welcome users and show them how to use BBB… and handling by that way, remote presentation file. (Cf UI)

 

We all know now, that real cobrowsing can’t be in Flash client due to restriction, and should be done using external tool, but as we spoke with Tiago an extra plugin/applet for user is to avoid … for now. But as you say, I completely agree, it should be an add-on extra feature, an applet which handle many things : webbrowser, upnp, h264, … to increase user experience, but a little bit harder to activate.

 

Perhaps in few weeks/month, a workgroup can be created to research and prototype that way ?

 

DJP

 

De : bigblueb...@googlegroups.com [mailto:bigblueb...@googlegroups.com] De la part de Jeremy Thomerson
Envoyé : vendredi 16 avril 2010 07:18

Jeremy Thomerson

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Apr 17, 2010, 12:57:34 AM4/17/10
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Ugggh....  That's what I get for replying in the middle of the night on such a long week - not even thinking about the fact that it's using WEBKIT - even though I clearly said that's what it's using, I didn't connect that it was Mac only.

Anyway, we could see if there are any rendering engines that will work in an applet.

Going to get some sleep.....

JT

Denis Zgonjanin

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Apr 17, 2010, 9:50:32 AM4/17/10
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I would still like to see this functionality in BBB even if someone decides to make a different prototype. I think being able to upload a document from a url anywhere on the internet is a pretty good feature. 
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