Andrew Pollack's Blog

Technology, Family, Entertainment, Politics, and Random Noise

Great way to determine if a user has editor access to a document using AJAX

By Andrew Pollack on 02/12/2007 at 11:54 AM EST

Warning, this post is extremely buzzword and acronym heavy!

I'm writing an application for the web right now that is entirely AJAX based, and uses back end Lotus Domino documents for data storage. Each back end document uses "READER" and "AUTHOR" names, but the code itself is all handled through agent calls made from the browser using AJAX.

In some cases, I want to display edit controls if the user has editor access to the document where the data is stored, but otherwise not. I tried doing this in the agents themselves when they read the data and write out the xml response for the AJAX call, but it's painful. To determine if they have editor access, you have to try to edit and save the target document. I have code to do that, but it would generate document updates every time a page is loaded by someone with editor access to those target documents

It occurred to me that I could do this with an AJAX call of my own. To understand this example, imagine I've read some data with an AJAX call and the resulting xml is in the variable "xml". One of the attributes in that result is the UNID of the document containing the source data. In this case, the "<group>" node has an attribute "unid". In xml it looks like this:

<group unid='321242523452345662323452352345' />

Given that this value is in the xml response, the following code extracts that value and creates a URL that if entered directly into a browser would open the target document in edit mode.

var grpunid = xml.getElementsByTagName('group')[0].getAttribute('unid');
var url = databasePath + "/0/" + grpunid + "?editdocument";

Now, I kick off another AJAX request while I'm processing the rest of the data....

ajaxRequest(url, null, setGroupEdit);
// < - in my case, a function called "ajaxRequest()" handles the meat and potatoes work, checks for errors, and passes the result
// in the variable "ajaxReq" to the function specified in the third parameter (in this case, setGroupEdit) when it finishes.

Finally, the function "setGroupEdit" is there to get the result of the background attempt to open the url in edit mode. All it has to do is check to see if the resulting response contains the text string "names.nsf?Login" which is what Domino would have generated if it had popped up the default session based login screen.

function setGroupEdit(ajaxReq) {
var txt = ajaxReq.responseText ;
if (txt.indexOf('names.nsf?Login') > 0) {
alert("Not an Editor");
} else {
alert("Yes, editor access");
}
}

As Bill points out, you have to watch for other things like "names.nsf!Login" or custom login forms -- but you get the point here, no? A bit ot tweaking to fit your specific case really should do it.

One last note: Since I don't let people edit that form directly, the form is designed so that with web access it has almost no content at all. That helps performance as well since the request and result are both very small.


There are  - loading -  comments....



Other Recent Stories...

  1. 09/04/2018With two big projects on hold, I suddenly find myself very available for new short and long term projects. In twenty five years, I don't think I've ever written an entry like this, but if you need the kind of work I do now would be a great time to get in touch. Both of the big projects I had lined up for late summer and early fall have been placed on hold and will be that way for a while. With the kids now all off at college and careers, I'm open to more travel than such than I have been in decades, but unless something else comes along, I'll be here working on updates to Second Signal and other things that ...... 
  2. 07/13/2018Who is HCL and why is it a good thing that they are now the ones behind Notes and Domino?We need to address some biases here. IBM has made a deal under which the Notes & Domino software and intellectual property is now being developed and maintained by HCL America. HCL America is part of the very large "HCL Technologies" company that has grown from its roots in India to become an 8 Billion Dollar company with a global presence in the IT Industry. You could be excused for initially believing, as many people do when they hear this, that "they've outsourced the code to India where they'll milk it ...... 
  3. 03/21/2018Domino Apps on IOS is a Game Changer. Quit holding back.BOOM. This will be as important for the platform as Traveler. If your company has ditched Notes and Domino, I feel sorry for you. For companies that do use Notes/Domino this is a game changer and Apple should be paying attention. Here's why: There are hundreds of little Notes client applications you'd never spend the time and money to build and deploy for your internal user base on IOS that we use Notes for all the time (those of us still using it). Now, those are suddenly ALL available on the iPad. ...... 
  4. 02/15/2018Andrew’s Proposed Gun Laws 
  5. 05/05/2016Is the growing social-sourced economy the modern back door into socialism? 
  6. 04/20/2016Want to be whitelisted? Here are some sensible rules for web site advertising 
  7. 12/30/2015Fantastic new series on Syfy called “The Expanse” – for people who love traditional science fiction 
  8. 10/20/2015My suggestion is to stay away from PayAnywhere(dot)com  
  9. 08/07/2015Here is one for you VMWARE gurus - particularly if you run ESXi without fancy drive arrays 
  10. 08/06/2015The Killer of Orphans (Orphan Documents) 
Click here for more articles.....


pen icon Comment Entry
Subject
Your Name
Homepage
*Your Email
* Your email address is required, but not displayed.
 
Your thoughts....
 
Remember Me  

Please wait while your document is saved.