Okay, I found my error. Somehow my catch-all construction had become empty instead of triggering an Ens.Alert....

I figured out there is a function called SendFormDataURL where you can include the tURL as the first parameter:

set tURL = ..Adapter.URL_"login/login"

set httpRequest = ##class(%Net.HttpRequest).%New()
    set httpRequest.ContentType="application/json"
    do ..ObjectToJSONStream(pRequest,.jsonStream,"aeliw")
    set httpRequest.EntityBody = jsonStream
    
    set tSC = ..Adapter.SendFormDataURL(tURL,.tHttpResponse,"POST",httpRequest)
    

Ok, I figured it out. Turns out I had to set the context of the business rule to BusinessProces.Context (and context with a capital C). The business rule then detected all my context variables when filling out the rules. Importantly I found that if you return a string value you must include "" and when you return a boolean you must use 0 or 1 (true or false doesn't work). Here is the code i used:

<ruleDefinition alias="" context="CareHome.NewEventRouter.Context" production="">
<ruleSet name="" effectiveBegin="" effectiveEnd="">
<rule name="Assess Event Code" disabled="false">
<when condition="EventCode=2103">
<assign property="EventDescription" value="&quot;Omschrijving&quot;"></assign>
<return>1</return>
</when>
<otherwise>
<assign property="EventDescription" value="&quot;Onbekende event-code&quot;"></assign>
<return>1</return>
</otherwise>
</rule>
</ruleSet>
</ruleDefinition>

When calling the rule from the business process I used:

<rule name='Fire Rule' rule='CareHome.DetermineEventFollowUp'  resultLocation='context.CreateCase' ruleContext='context' xpos='200' ypos='350' >
</rule>

Important here is that if you include a resultLocation, you must give a return value in the business rule otherwise the value context.CreateCase is cleared (it had a default value of 0). Also, notice that the resultLocation is not required. An alternative implementation is to leave it empty and use assign in the business rule for both EventDescription and CreateCase.

Ok I have updated my question with the actual code.

I figured out how to work with the <return> value, and I think that the assign might work as well, but I just can't get the condition to work. I doesn't seem to trigger on "request.EventCode=2103" even though the BPL processes a message where the request.EventCode=2103.

Yes, I am aware that you can call a Transform and then fill the context in a BPL-process. It is very important trick I think. However, I have the feeling that a business rule will be more manageable than a data transformation assigning values to 150 different codes.

Ok I updated the apache.conf and it seems to work now. This is what I ended up with:

<Directory "/home/ubuntu/intersystems/fcoffice/csp/healthshare/fcoffice/rest">
    CSP On
        SetHandler csp-handler-sa
</Directory>
<Directory "/home/ubuntu/intersystems/fcoffice/csp">
    CSPFileTypes csp cls
    AllowOverride None
    Options MultiViews FollowSymLinks ExecCGI
    Require all granted
    <FilesMatch "\.(log|ini|pid|exe)$">
        Require all denied
    </FilesMatch>
</Directory>

I found this in the apache2.conf

<Directory "/home/ubuntu/intersystems/fcoffice/csp">
    CSPFileTypes csp cls zen cxw
    AllowOverride None
    Options MultiViews FollowSymLinks ExecCGI
    Require all granted
    <FilesMatch "\.(log|ini|pid|exe)$">
        Require all denied
    </FilesMatch>
</Directory>

I presume I somehow need to add url's here. How? I can't find any suggestions/examples in the documentation.