Interesting, will maybe pursue at a later date - Jeffrey's suggestion above works for us, and we've also got organisational constraints on what browser extensions we are allowed to install, which makes trying this non-trivial.

This is fantastic - exactly what we were looking for. Thanks!

Yeah, should have said we've used that - but we've not figured out how to use VDoc specifications or their equivalent to output specific fields from the HL7 message as you can in the message viewer. In the SQL text shown by "Show Query" you get something like:

null As FieldName

where the column specified in the message viewer via a VDoc display specification would be.

Query in Message Viewer includes display item: 

This produces SQL query below:

A basic pass-through can be achieved by:

• HL7 TCP Service with Ack Mode set to Application
• no message router/business process
• HL7 TCP Operation, with Reply Code Actions set to :?R=C,:?E=C,:~=C,:?A=C,:*=C,:I?=W,:T?=C
• this basically says that the pass-through interface will treat every message which receives an ACK (of any kind) from the downstream as Completed (C), and so pass the received ACK back to the upstream.

Thanks @Eduard Lebedyuk for replying - we've already got ACK Mode set to Application.

Further investigation has revealed that:

• an "AA" (successful) ACK is passed back from the downstream to the pass-through interface and from the pass-through to the upstream when the business service (HL7 TCP) is connected directly to the business operation (HL7 TCP). This is (successful message) behaviour we want.
• an "AE" (unsuccessful) ACK from the downstream causes the business operation in the pass-through to suspend the message under default Reply Code Actions, and no ACK is send back from pass-through to the upstream. We want the AE ACK to be passed back through the pass-through to the upstream. 
• When a Message Router business process sits between the business service and the business process in the pass-through interface then (with current settings) then an ACK is generated by the Message Router and sent back to the upstream before any ACK (AA or AE) is received back from the downstream.

So our questions:

1. What Reply Code Actions applied to the business operation in the pass-through will not suspend messages which result in an AE (error) ACK, but pass that ACK back to the upstream? (We are continuing to experiment/read to see if we can do this.)
2. Is it possible to force an HL7 Message Router to be synchronous and wait for the ACK from the business operation, rather than defaulting to be asynchronous?

Perfect, thanks!

Thanks, that's really helpful - we'll have a play and see whether we can configure that to tell us what we are interested in.

We are using a source control solution - for the code we develop - the problem is that the other groups (an external contractor doing development, and a platform management team making config changes, mostly in the Production class) don't use our source control. So we are having to manually merge changes made by others back into active development branches - and organisationally / given the historical situation with multiple interacting interfaces built in a single namespace, there's not a lot we can do to change that context. So an audit of who changed what when is probably the best we can get for now...

Thanks Brett, that's very helpful. Have tried out the various combinations of VS Code import and export of code and also $SYSTEM.OBJ.Load() / .Export() / .ExportUDL() and what we are seeing matches your description. I suspect we'll never know how the affected classed got into our codebase in the first place, but now that we know what's going on we can make some attempt to manage the situation.

Thanks for replying:

1. Not really what @Brett Saviano, one of the ISC maintainers of the VS Code extension, said in previous discussion on the extension's github page.
2. Yup
3. But how? Try and edit, using either Studio or VS Code, to produce a '//XXX' comment (no space) outside a method definition. You can't do it - the space is generated by the editors without your intervention. Hence my question - how did that space get into Ensemble in the first place?
4. Yup
5. In principle its not just commented out Property's, it seems to be any '//' comment with no space after the '//' when that comment is not within a method (or classmethod) definition. And finding the couple of hundred classes with such comments across a 4000 class file production is a non-trivial exercise!

Sorry, should have linked earlier discussions:

• VS Code ObjectScript extension error | InterSystems Developer Community |
• Request textDocument/documentSymbol failed. Error: name must not be falsy · intersystems-community/vscode-objectscript · Discussion #1530  

Hmm, attachment isn't showing. Tried again, didn't work, so have pasted the text of the export file below:

<?xml version="1.0" encoding="UTF-8"?>
<Export generator="Cache" version="25" zv="Cache for Windows (x86-64) 2018.1 (Build 184U)" ts="2025-04-30 08:23:56">
<Class name="SCI81.s1.PatientNotification">
<Description>
Created from: http://fv-testscistore/storews/store81/scistoreservices.asmx?WSDL</Descr...
<ProcedureBlock>1</ProcedureBlock>
<Super>%SerialObject,%XML.Adaptor</Super>
<TimeChanged>63768,58466.681212</TimeChanged>
<TimeCreated>63767,58804.718434</TimeCreated>

<Parameter name="ELEMENTQUALIFIED">
<Default>1</Default>
</Parameter>

<Parameter name="NAMESPACE">
<Default>http://www.show.scot.nhs.uk/isd/SCIStore</Default>
</Parameter>

<Parameter name="XMLNAME">
<Default>PatientNotification</Default>
</Parameter>

<Parameter name="XMLSEQUENCE">
<Default>1</Default>
</Parameter>

<Property name="PatientID">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="PatientID"/>
</Property>

<Property name="MergeID">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="MergeID"/>
</Property>

<Property name="EventType">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="EventType"/>
</Property>

<Property name="Consent">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="Consent"/>
</Property>

<Property name="TransactionType">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="TransactionType"/>
</Property>

<Property name="CHI">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="CHI"/>
</Property>

<Property name="RecordType">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="RecordType"/>
</Property>

<Property name="RecordKey">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="RecordKey"/>
</Property>

<Property name="ProcessEvents">
<Type>%String</Type>
<Parameter name="MAXLEN"/>
<Parameter name="XMLNAME" value="ProcessEvents"/>
</Property>

<UDLText name="T">
<Content><![CDATA[
//Property any As list Of %XML.String(XMLNAME = "any", XMLPROJECTION = "ANY") [ SqlFieldName = _any ];

]]></Content>
</UDLText>

<Storage name="Default">
<Type>%Library.CacheSerialState</Type>
<State>PatientNotificationState</State>
<StreamLocation>^SCI81.s1.PatientNotificationS</StreamLocation>
<Data name="PatientNotificationState">
<Structure>listnode</Structure>
<Subscript/>
<Value name="1">
<Value>PatientID</Value>
</Value>
<Value name="2">
<Value>MergeID</Value>
</Value>
<Value name="3">
<Value>EventType</Value>
</Value>
<Value name="4">
<Value>Consent</Value>
</Value>
<Value name="5">
<Value>TransactionType</Value>
</Value>
<Value name="6">
<Value>CHI</Value>
</Value>
<Value name="7">
<Value>RecordType</Value>
</Value>
<Value name="8">
<Value>RecordKey</Value>
</Value>
<Value name="9">
<Value>ProcessEvents</Value>
</Value>
<Value name="10">
<Value>any</Value>
</Value>
</Data>
</Storage>
</Class>
</Export>

I'm also seeing the Language Server output disappearing from the drop-down now! @Brett Saviano is responding more fully on the GitHub forum linked above.

Thanks for looking. Realised that I gave the version number for the ObjectScript extension (3.0.1), but not for the Language Server (2.7.2). And as you've highlighted its the language server which is giving me the error.

Thanks, @Enrico Parisi, that looks a good starter for the kind of thing we are exploring.  

Thanks for the link, but as we are stuck on Ensemble (not Iris), we can't make use of this.