Skip to main content

APEX (Multi) Application Settings

By
Most applications need some sort of "configuration" table. A simple key-value store where you can put values that might change on a different environment, like URLs, minimal password length, API keys, etc. And very conveniently APEX has this implemented as "Application Settings": A simple table containing a key and a value - and a few other properties like "valid values". In your code you can reference these values using either the apex_application_settings view - that contains all Application Settings in your Workspace - or the apex_app_setting API - that you can use to get or set a value based on the Application Settings Name.

That's all great. Until I ran into this situation: Our "application" consists of 2 APEX applications, one Internal (INT), backoffice kind of application and one external (EXT) facing one. And now I needed to set the Application Setting of the EXT application from the INT application. While I can see the current values of the EXT Application Settings - as the apex_application_settings view shows me all settings in my Workspace, I cannot simply set it using the apex_app_setting API as "This procedure changes the application setting value in the current application". So how can I use that to set that API to set the value in another application?
My first idea was to create a Form Page with a Process calling that API in the EXT app and just link to that Form Page from my INT app. That could have worked if both applications would have used the same Authentication cookie. Which of course they didn't!

So as the API can only set a value in the current application .... I had to switch the current application during a Form process that does the update. And there the apex_session package comes to the rescue!
So upon update, when the Application Setting is not a setting of the current application, I have to detach from the current (APEX) session and create a new session for the other (EXT) application. Then I can set the value using the apex_app_setting API. Once done, I can delete that APEX session and attach back to my original session. So the next processes in my APEX page (like "Close Dialog") will still work. 

begin 
  if :P235_APPLICATION_ID = :APP_ID then         
    apex_app_setting.set_value( :P235_NAME, :P235_VALUE );
  else
    -- Switch to other / new session in the other App
    apex_session.detach;
    apex_session.create_session (p_app_id => :P235_APPLICATION_ID, p_page_id => 0, p_username => :APP_USER);
    apex_app_setting.set_value( p_name => :P235_NAME, p_value => :P235_VALUE );
    apex_session.delete_session;
    -- Return to the original session
    apex_session.attach( p_app_id => :APP_ID, p_page_id => :APP_PAGE_ID, p_session_id => :APP_SESSiON );
  end if;  
end;

Simple. Elegant. And just using the APEX API's! 

Comments

Post a Comment

Popular posts from this blog

How to create neatly formatted Excel documents using PL/SQL?

By
If there is a requirement to produce output from an application into Excel, you would probably create a CSV (Comma Separated File) with the data and start Excel to show the data - at least that's what I did...until now. The drawback of this solution is that you could only produce data and no nice layout. But Excel is also capable of opening HTML-files and using this you could create Excel files with data and magnificent layout! Let me give an example: 1. Create a procedure to show the data in formatted in an HTML table. CREATE OR REPLACE PROCEDURE display_emp_list IS v_emp_count NUMBER(5); v_empno NUMBER(8); v_ename VARCHAR2(50); v_job emp.job%TYPE; v_sal emp.sal%TYPE; v_bg_color VARCHAR2(10) := ''; CURSOR c_emp IS SELECT empno, initcap(ename), job, sal FROM emp ORDER BY ename; BEGIN SELECT COUNT(*) INTO v_emp_count FROM emp; owa_util.mime_header('application/ms-excel', FALSE); htp.p('Content...
21 comments
Read more

Refresh selected row(s) in an Interactive Grid

By
In my previous post I blogged about pushing changed rows from the dabatase into an Interactive Grid . The use case I'll cover right here is probably more common - and therefore more useful! Until we had the IG, we showed the data in a report (Interactive or Classic). Changes to the data where made by popping up a form page, making changes, saving and refreshing the report upon closing the dialog. Or by clicking an icon / button / link in your report that makes some changes to the data (like changing a status) and ... refresh the report.  That all works fine, but the downsides are: The whole dataset is returned from the server to the client - again and again. And if your pagination size is large, that does lead to more and more network traffic, more interpretation by the browser and more waiting time for the end user. The "current record" might be out of focus after the refresh, especially by larger pagination sizes, as the first rows will be shown. Or (even wors...
Post a Comment
Read more

APEX ReadOnly Pages - The easy way

By
If your Oracle APEX Application requires different types of access - full access or readonly - for different types of users, you can specify a Read Only Condition on Page level (or Region, Item, Button, etc.).  You can set an Authorization Scheme on Application level, so it'll be applied to all pages. So if you have an Authorization Scheme named 'User Can Access Page' defined by a PL/SQL function like this: return apex_authorization.user_can_access_page ( p_app_id  => :APP_ID , p_page_id => :APP_PAGE_ID , p_user    => :APP_USER );  then you can code all the logic in the database using the APEX Repository, your own tables or a combination to define whether a user has access to that page or not. But alas it is not possible to define something similar Application wide for a Read Only condition. You can specify an Authorization Scheme 'User has Read Only Access' using a similar signature as the one above and use that on each and e...
Post a Comment
Read more