Using your code (simplified by me) from terminal it works fine using a sample CCDA from here.

set ccdaStream = ##class(%Stream.FileBinary).%OpenId("c:\temp\CCDA_CCD_b1_Ambulatory_v2.xml")
write "Size of CCDA Stream: ", ccdaStream.Size,!
set xsltTransform = "SDA3/CCDA-to-SDA.xsl"
set tTransformer = ##class(HS.Util.XSLTTransformer).%New()
set tSC = tTransformer.Transform(ccdaStream, xsltTransform, .sdaStream)
if 'tSC write "Transformation to SDA3 failed with error ",$system.Status.GetErrorText(tSC),!
set fhirStream = ##class(%Stream.TmpBinary).%New()
set SDA3ToFHIRObject = ##class(HS.FHIR.DTL.Util.API.Transform.SDA3ToFHIR).TransformStream(sdaStream, "HS.SDA3.Container", "R4")
if '$isobject(SDA3ToFHIRObject.bundle) write "Failed to transform SDA3 to FHIR",!
do SDA3ToFHIRObject.bundle.%ToJSON()

The result/output is a pretty long JSON FHIR bundle with CCDA data (I didn't check the content!)

Does your code works with that sample CCDA?

If not, then maybe there is something wrong in your CCDA.

For my test I used: IRIS for Windows (x86-64) 2024.1 (Build 267_2U) Tue Apr 30 2024 16:35:10 EDT

In my opinion, if you need to encode a file/stream "as is", without any conversion, so that the counterpart receiver get EXACTLY what your source file/stream is/was, then use %Stream.FileBinary.

If you need some character conversion (say, Unicode/UTF8 or others), then use %Stream.FileCharacter (with appropriate parameters...) that can handle the conversion.

I'm a little puzzled, according to documentation the method %FromJSONFile() it's not implemented in version 2022.3, it has been implemented in 2024.1, so I don't understand why you get that error, I'd expect a <METHOD DOES NOT EXISTS> error, but I don't have version 2022.3 at hand to test.

In any case, for IRIS versions that implement the %FromJSONFile() method, please note that the parameter to pass is the filename, not a %File object instance.

Form class reference of the %Library.DynamicAbstractObject class the first parameter is documented as:

filename A file URI where the source can be read.

So, the code should be:

set newObject = {}.%FromJSONFile("/tmp/longObjectFile.txt")

Why define and reference an outbound adaptor when you don't use it in your code?
I'd suggest to have a look to the documentation Using the HTTP Outbound Adapter.

Anyway, given your code, you don't need a stream, it's just waste of resources and make your code more complicated for no reason, you can simply:

....
Set httpRequest.ContentType = "application/xml"
Do httpRequest.EntityBody.Write("<?xml version=""1.0"" encoding=""UTF-8""?><getURL>"_pRequest.getURL_"</getURL>")
Set sc = httpRequest.Post("", 2)
....

Note that I assume that <Url1></Url1> is contained in the getURL string property content, as your first post suggest.

I'm not sure if this apply to your case but in the past we found that a very old database (20+ years) that has been upgraded many time over the years had bitmap indices "not compacted" and we gained a lot of space and, more importantly, huge performance improvement running %SYS.Maint.Bitmap documented here:

This utility is used to compact bitmap/bitslice indices. Over time in a volatile table (think lots of INSERTs and DELETEs) the storage for a bitmap index may become less efficient. To a lesser extent index value changes, i.e. UPDATES, can also degrade bitmap performance.

The first parameter (Lookup Table Name) of Exists function must be quoted: Exists("HologicProcedureFilter",.....)

If you want, you can switch to the old zen based rule editor, in the upper right of the page click on the user icon and select Open in Zen rule editor:

Note that it will open the rule in new tab, leaving the old tab open, make sure you use only one tab to edit the rule!

Assuming response1 json ALWAYS contain a single entry, then:

    ; import stream into Dynamic Object
    Set Response1=##class(%DynamicObject).%FromJSON(response1.informesAutorizadosRangoFechas)
    Set Response2=##class(%DynamicObject).%FromJSON(response2.informesAutorizadosRangoFechas)
    
    Write "Response1 has ",Response1.entry.%Size()," entries",!
    Write "Response2 has ",Response2.entry.%Size()," entries",!

    ; loop all the entries in Response2
    Set EntryIter=Response2.entry.%GetIterator()
    While EntryIter.%GetNext(.EntryKey, .Entry) {
        Write "Response2, entry ",EntryKey+1," has ",Entry.resource.%Size()," resources",!

        ; loop all resources within Entry
        Set ResourceIter=Entry.resource.%GetIterator()
        While ResourceIter.%GetNext(.ResourceKey, .Resource) {

            ; add resource from Result2 in first entry of Result1
            Do Response1.entry.%Get(0).resource.%Push(Resource)  
        }   
    }
    Write "Merged Response1 has ",Response1.entry.%Get(0).resource.%Size()," resources",!

Using your samples the output is:

Response1 has 1 entries
Response2 has 7 entries
Response2, entry 1 has 1 resources
Response2, entry 2 has 1 resources
Response2, entry 3 has 1 resources
Response2, entry 4 has 1 resources
Response2, entry 5 has 1 resources
Response2, entry 6 has 1 resources
Response2, entry 7 has 1 resources
Merged Response1 has 8 resources

The resulting json is different than your manual merge.......