IF we use cookies, they will be stored in the Session Cookie Path.

Cookie has a property named path. Whed browser determines, does the cookie apply to a current page, it checks if the cookie path is less or equal to current URL.

I'm thinking that this login cookie would be used somehow if the Login Cookie is selected? Or not used? 

It would be used, if checked.

what does happen if the Login Cookie is selected in the web application?

What could we store in a cookie? Can we possibly find out if a second tab has been opened by using a cookie?

You can store text values in cookie. I suggest you read wiki article on them.

Here are some thoughts:

• Write Source Control Hook that implemets OnAfterSave method and checks there (or maybe some other entry point). There are several sample source control hook classes, check them out.
• Use ^rINDEXCLASS global (key - class name in uppercase) - it contains some basic information such as modification time (1st position) and hash (13th position). You can monitor it and if time or hash changes then record the new class version.
• Use lock table to see what classes are currently being edited
• Use $$$defClassKeyGet macros (see %Dictionary.ClassDefinition/%Dictionary.CompiledClass definitions, they use these macros a lot) to get info about modification time/hash and the changes themselves
• %Compiler.UDL.TextServices to get the class text

I would have done it like this:

• Background process monitors ^rINDEXCLASS global
• Upon finding changes get the current class code via %Compiler.UDL.TextServices class,  GetTextAsStream method
• Write this information into your own class (classname, timestamp, user, classtext, diff, previousversion)

Modification of system classes is not a very good idea:

• They are lost on update
• User may not have access required to install these changes

That being said, the best solution in my opinion is to setup your critical/production systems in such a way, that developers do not have direct write access to them. Each of the developers have their own environment where they can do whatever and then commit it to source control system. Continuous integration solution (or one developer or a script) then uploads the code (after it passes the tests) to the production server. There are several source control/continuous integration systems available for Caché.

It is a good idea that a change can only be done via source control commit. All other changes simply should not exist.

There is a beforeunload HTTP event which is fired when the window, the document and its resources are about to be unloaded. Handle this event in your js code and from there you can send an HTTP request to a server (I usually use GET /webapp/logout), which would do something like this:

ClassMethod logout() As %Status
{
    #dim %session As %CSP.Session
    set st = %session.Logout(1)
    set %session.EndSession = 1
    return st
}

Index NewIndex1 On PropertyD(ELEMENTS);

Documentation.

 I'd also love to see the web application's properties programmatically, if possible (such as the physical files path).

Use Security.Application class directly, or preferably via %Installer manifest.

but I honestly don't know why it's choosing that web application over the default of /csp/default-namespace

Uncompile and compile ZEN classes after setting default web application. Or you can try to set HOMEPAGE parameter in the application class.

My question is, if we go to using Group By ID (which is currently null) in the web application, will this fix the sharing of %session Data? (This is why I have to make sure I'm editing the correct web application!)

If the user opens one web application in two tabs, they would be sharing a session (and namespace). Group By ID would only help if you have N different applications and would specify N different values for Group By ID property. In that case, they should use N different sessions.

Finally, we have a web application for each namespace; will we need the Group By ID for each application defined for each namespace, and should it be the same ID?

Depends, if you want to share %session or not.

Then you need to specify MODE attribute as LOGICAL for that cspbind property. Documentation.

Sure, execute this in a terminal to open a new terminal for an instance named cache:

do $zf(-2,"cterm.exe /console=cn_ap:cache")

$ZF(-2) docs, cterm docs.

Simpliest way: Cache executes an operating system command via $zf(-1) function.

Alternatively, you can load a dll with $zf(-4) (also 3, 5) functions.

There is also CNA project - it provides an interface for using native C-compatible shared libraries without anything but Caché ObjectScript code. CNA is a wrapper for libffi. CNA consists of native library (libcna) and Caché class (CNA.CNA). It is a wrapper around $zf functions.

That said, the most effective would be some kind of a library load with library written in either C or generated from some computational language. For example Mathlab can generate C code, which can be then compiled into a library.

Something like this? I had a similar problem, but the check was required only for part of the properties. If you want all of them, remove the line with continue.

Method IsEmpty() As %Boolean [ CodeMode = objectgenerator ]
{
    For i = 1:1:%class.Properties.Count() {
        Set Prop = %class.Properties.GetAt(i)
        CONTINUE:(Prop.Internal || Prop.Calculated || Prop.ReadOnly || Prop.Private || Prop.Identity)
        
        Do %code.WriteLine(" Quit:.." _ Prop.Name _ "'="""" $$$NO")
    }
    Do %code.WriteLine(" Quit $$$YES")
}

1. Inherit from EnsPortal.MessageViewer
2. Copy searchPane from EnsPortal.Template.filteredViewer
3. In searchPane, TimeFormat node replace attribute  value="12" with value="999"
4. Compile. Your new class would have Complete as TimeFormat default value

Alternatively, instead of 2-4 you can set TimeFormat value in your class by overriding some init callback ( %OnAfterCreatePage maybe, don't forget to call ##super() though) and setting it there. It would be a better solution.

2020 UPDATE.

I think I found a better solution.

1. Extend EnsPortal.MsgFilter.Assistant class.

2. In this class redefine EnumerateExecute method to provide the desired format. Replace this line:

Do ..addTerm(.aSelect,"{fn RIGHT(%EXTERNAL(head.TimeCreated),"_dateLen_"
)} As TimeCreated")

to provide the format you need.

Alternatively redefine OnFinalizeSQL to replace

{fn RIGHT(%EXTERNAL(head.TimeCreated),999)}

with something else.

3. Set the global

^EnsPortal.Settings("MessageViewer","AssistantClass")

to the value of your class.

This looks like an official way to modify MessageViewer behavior.

Sorry, I forgot that SYS.Database is deployed. You'll need to match $zu(49) to properties manually. But the macros usually have the same name. For example field 14 is sfnpiece macro ("piece" part of the name is irrelevant, so just sfn it is) and it corresponds to SFN property in SYS.Database.

To test, you can write the following method:

ClassMethod Test( Directory )

{
    Set db=##Class(SYS.Database).%OpenId(Directory)
    Write db.SFN = $p($zu(49),",",$$$sfnpiece) //14th piece
    // More checks
}

I export/import ^DeepSee.Variables global.

I imported your example, executed:

Do ##class(Wendy.LTCodes).SetData()

Then executed this sql:

SELECT
ID, Code, Description, Invalid
FROM Wendy.LTCodes

and received the following results:

seems to be working.

But then I didn't really understand the use of Parameter InvalidGLVN = "^Utils.GlobalPropP";

it's for use with indirection.  Example:

set ^Utils.GlobalPropP = 123
set glvn = "^Utils.GlobalPropP"
write glvn
> ^Utils.GlobalPropP
write @glvn
> 123

Your error:

<INVALID 0REF>zSrvGetData+2

Points to the line;

set item = ..%GetComponentById("Item").value

And means that the result of this call:

..%GetComponentById("Item") 

Is not an object, so you can't access a property "value".

Why not use %Stream.FileBinary and %Stream.FileCharacter?  It would store the file outside of the database.

If our SVN repository already is storing discrete .cls files, does Atelier do any conversion when we load from SVN into our server instance?

No, except maybe for repository structure. That depends is Atelier + EGit support repository structure you use. For how to use EGit with Atelier check this article.

At what point would I see .udl files? I am thinking I would only see that if SVN was storing .xml and each of those would be converted to .udl.

There are no .udl files. There are just cls/mac/inc etc files in udl format, meaning they are represented on disk as is and not in the xml format. The extension would be .cls and so on. Here's the sample repository created with Atelier.

Here's the documentation detailing  the process.

Or do you have more specific questions?

%Label is the way to go.

Its fifth argument is a CSS applied to a cell. So the following MDX:

SELECT NON EMPTY %LABEL([Measures].[%COUNT],,,,"width:100%") ON 1 FROM [HOLEFOODS]

Would be displayed like this in analyzer:

And its sixth argument is a CSS applied to the cell header:

SELECT NON EMPTY %LABEL([Measures].[%COUNT],,,,,"width:80%") ON 1 FROM [HOLEFOODS]

Alternatively you can use DeepSeeWeb to display dashboards with pivots. In there cells width can be easily modified.

You can close the cursor and open it again:

ClassMethod Test()
{
     &sql(  DECLARE C1 CURSOR FOR
            SELECT TOP 10 ID
            INTO :id
            FROM Sample.Person
    )

    &sql(OPEN C1)
    &sql(FETCH C1)
    
    Set first = $$$YES

    While (SQLCODE = 0) {
        Write id,!       
        &sql(FETCH C1)
        If id=9 && first {
            Set first = $$$NO
                &sql(CLOSE C1)
                &sql(OPEN C1)
                &sql(FETCH C1)
        }
    }

    &sql(CLOSE C1)
}

write $System.Util.CreateGUID()

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