AllAccepted answers
Julius Kavay · Oct 12, 2020

it's easy, without AM/PM

write $tr("abcd-ef-gh ij:kl:00","abcdefghijkl",202010011000),! // ODBC-Format
write $tr("gh.ef.abcd ij:kl:00","abcdefghijkl",202010011000),! // German-Format
write $tr("ef/gh/abcd ij:kl:00","abcdefghijkl",202010011000),! // US-Format

but if you need AM/PM, then the shortest way is using $zd()/$zth() functions

set datetime=202010011000
set tmp=$tr("abcdefgh ij:kl:00","abcdefghijkl",datetime) // or using $e(...)
set tmp=$e(datetime,1,8)_" "_$e(datetime,9,10)_":"_$e(datetime,11,12)_":00" write $zdt($zdth(tmp,3),1,3)

Julius Kavay · Oct 8, 2020

To make your (and others) life easier... here is a simple class to display a dynamic object (or dynamic array).

/// A general class for various helper functions
/// 
Class %zapi.utils Extends %RegisteredObject
{ /// Show an dynamic array or object
/// 
/// obj : the dynamic object (or array) you want to display
/// deep: max path depth, 0 (default) = display all
/// find: if given, (a part of) a property name
ClassMethod ShowObj(obj, deep = 0, find = "")
 {
   new %seen
   do ..shObj(obj,deep-1,find,"<obj>")
 }
ClassMethod shObj(obj, deep, find, path) [ Internal, Private ]
 {
   set path=path_"."
   set itr=obj.%GetIterator()
   while itr.%GetNext(.prop,.val) {
      set:obj.%IsA("%DynamicArray") prop="%Get("_prop_")"
      set prop=path_prop
      if $isobject(val) {
         if $data(%seen(+val)) { set val="same as --> "_%seen(+val)
         } else { set %seen(+val)=prop }
      }
      if $isobject(val),deep { do ..shObj(val,deep-1,find,prop)
      } else { write:prop[find prop,": ",val,! }
   }
 }
}

With our old pData,  use it as follows:

write pData 
[{"patient":{"guid":"12345","id":12345,"forename":"Joe","surname":"Bloggs","dateOfBirth":"2002-12-10T00:00:00Z"},"visit":[{"guid":45678,"date":"2020-01-10","reason":"other"},{"guid":45679,"date":"2020-01-11","reason":"routine"}],"
documentAttachments":[{"guid":"23432","id":152,"catergory":"notes"},{"guid":"23433","id":153,"catergory":"summary"}]}]

set obj={}.%FromJSON(pData)
do ##class(%zapi.utils).ShowObj(obj)

If you don't want to write each time a novel, you can create your own "show object" command too.
Insert the following line into %ZLANGC00 routine (if %ZLANG doesn't exists, create it):

ZSHO(obj, deep=0, find="") Public { do ##class(%zapi.utils).ShowObj(obj,deep,find) }

and Voila!, you got a short command to display dynamic objects

zsho obj              // display the whole object
zsho obj:2            // display up to  second nesting level
zsho obj::"visit"     // display all occurrences of property visit
zsho obj::"guid"      // display all occurrences of property guid

The outputs of the above commands are

USER>zsho obj
<obj>.%Get(0).patient.guid: 12345
<obj>.%Get(0).patient.id: 12345
<obj>.%Get(0).patient.forename: Joe
<obj>.%Get(0).patient.surname: Bloggs
<obj>.%Get(0).patient.dateOfBirth: 2002-12-10T00:00:00Z
<obj>.%Get(0).visit.%Get(0).guid: 45678
<obj>.%Get(0).visit.%Get(0).date: 2020-01-10
<obj>.%Get(0).visit.%Get(0).reason: other
<obj>.%Get(0).visit.%Get(1).guid: 45679
<obj>.%Get(0).visit.%Get(1).date: 2020-01-11
<obj>.%Get(0).visit.%Get(1).reason: routine
<obj>.%Get(0).documentAttachments.%Get(0).guid: 23432
<obj>.%Get(0).documentAttachments.%Get(0).id: 152
<obj>.%Get(0).documentAttachments.%Get(0).catergory: notes
<obj>.%Get(0).documentAttachments.%Get(1).guid: 23433
<obj>.%Get(0).documentAttachments.%Get(1).id: 153
<obj>.%Get(0).documentAttachments.%Get(1).catergory: summary

USER>zsho obj:2
<obj>.%Get(0).patient: 11@%Library.DynamicObject
<obj>.%Get(0).visit: 2@%Library.DynamicArray
<obj>.%Get(0).documentAttachments: 21@%Library.DynamicArray

USER>zsho obj::"visit"
<obj>.%Get(0).visit.%Get(0).guid: 45678
<obj>.%Get(0).visit.%Get(0).date: 2020-01-10
<obj>.%Get(0).visit.%Get(0).reason: other
<obj>.%Get(0).visit.%Get(1).guid: 45679
<obj>.%Get(0).visit.%Get(1).date: 2020-01-11
<obj>.%Get(0).visit.%Get(1).reason: routine

USER>zsho obj::"guid"
<obj>.%Get(0).patient.guid: 12345
<obj>.%Get(0).visit.%Get(0).guid: 45678
<obj>.%Get(0).visit.%Get(1).guid: 45679
<obj>.%Get(0).documentAttachments.%Get(0).guid: 23432
<obj>.%Get(0).documentAttachments.%Get(1).guid: 23433

Have a nice day...

Julius Kavay · Oct 7, 2020

It's simple and easy... just follow the picture (I meant, the JSON string):

[
  {
    "patient":
      {
        "guid":"12345",
        "id":12345,
        "forename":"Joe",
        "surname":"Bloggs",
        "dateOfBirth":"2002-12-10T00:00:00Z",
        "NOK":[
                {
                   "NOKname":"Alison Bloggs",
                   "NOKrelationship":"Wife",
                   "telephone":"02081234567",
                   "email":"alison@bloggs.com"
                }
              ]
      }
  }
]

Now we create a dynamic Object:

set obj = {}.%FromJSON(pData)

Your pData is a JSON-Array, where the (array)elements/items are objects

 (we have just one elemment), so we can say:

set item = obj.%Get(0)

This  item object has a patient property, which is an object, so we go one step deeper

set item = obj.%Get(0)
set patient = item.patient 
set patient = obj.%Get(0).patient  // same as above

Our patient object has properties like guid,  id,  forename, surname, dateOfBirth and NOK. 

The property NOK itself is, again, an array where the array elements/items are objects.

set nok = patient.NOK
set nok = obj.%Get(0).patient.NOK // same as above

Now, we know, our property NOK is an array, so we have to take of those elements. This nok elements are objects, so we can take the properties (NOKname, ...email):

set nokItem = nok.%Get(0)
write nokItem.NOKname," ",nokItem.email,!

or, all in one line

write obj.%Get(0).patient.NOK.%Get(0).NOKname,!

Now all together, a small routine to print out all NOKxxxx properties:

set obj = {}.%FromJSON(pData)
for i=0:1:obj.%Size()-1 { // loop over pData items grabbing patient props
    set patient = obj.%Get(i).patient
    for j=0:1:patient.NOK.%Size()-1 { // now we loop over all NOK items
        set nok = patient.NOK.%Get(j)
        write nok.NOKname,!
        write nok.NOKrelationship,!
    }
}

So I hope, you see the light at the end of the tunnel...

Julius Kavay · Oct 6, 2020

According to above sample data, your JSON-Data (pData) is :

- an array of one or more objects

- the object(s) have "patient", "visit" and "documentAttachments" as properties

- the "patient" property is an object and has "guid", "id", "forename", "surname", and "dateOfBirth" as properties

So, to get the "forename" property, you have to do something like:

set object = {}.%FromJSON(pData)  // create a JSON-Object from JSON string
write object.%Get(0).patient.forename  // 

or step by step

set firstArrayItem = object.%Get(0) // first array item is 0
set patient = firstArrayItem.patient // this is the patioent object
write patient.forename  // now you have the name
write patient.surname // and other properties

By the way, the "visit" property is also an array! To list all the "reason" properties, you have to write a loop:

set visit = firstArrayItem.visit  // the first visit 
for i=0:1:visit.%Size()-1 {
  write visit.%Get(i).reason,!
}

Your output will be:

other

routine

I hope, things are now more clear? 

Julius Kavay · Oct 5, 2020

The problem is obvious, your set object = ##class(%DynamicAbstractObject).%FromJSON(pData) won't work, because pData contains an invalid JSON!

1) "visit":[{"guid":45678" <-- surplus QUOTE-char, maybe a typo

2) reason":"other"} {"guid":45679    missing comma between } and {

3) "catergory":"notes"} {"guid":"23433" missing comma between } and {

You  can use https://jsonlint.com/ to check your JSON string.

Julius Kavay · Oct 2, 2020

The above should work, so the question is, what is the content of pData. Do you can share a sample with us?

Also, you can write the above somewhat shorter too and you can access all the properties either via propertyname or via the %Get() method.

I assume, you have a string like this:

set pData="{""Name"":""Joe"", ""Age"":50}"

the you can do this

set object={}.%FromJSON(pData)
write object.Name // Joe
write object.%Get("Name") // Joe
write pData // {"Name":"Joe", "Age":50}
Julius Kavay · Sep 27, 2020

Now we have the year 2020 (but I will discard this year from my life because of Covid-19) but our loved COS wasn't in this year nor in  the very past years invented.

COS (better, the predecessor, M ) has more then 50 years under his belt, it was created in the late sixties - in a time, where RAM was rare, expensive and therefore it was measured in units of kilobyte!

If I recall correctly, at end of the seventies, we had some customers on a PDP-11/34 with less then 64KB of memory, one or two 2kb partitions and some "big" partitions with 4KB or 6KB, the rest was for disk buffers (512 byte each) and DEC's V4b (which acted as OS, database and language interpreter).

Hence the ability of COS for excessive abbreviations and if you get an old routine, written by an old school programmer (like me) then you will see there (mostly) abbreviated commands,  postconditions and (local-/globalvariable, label and routine) names, consisting just a few letters (one to three, maybe four).

Unfortunately, this (abbreviated commands, short names) happens to me in this days too - you know, old habits never die.

There is a wonderful (and at the same time a horrific) example of such a routine: one letter names, everything abbreviated:
https://stackoverflow.com/questions/4151554/need-mumps-sample-code/4430996

clock ;; a digital clock from
;; https://stackoverflow.com/questions/4151554/need-mumps-sample-code/4430996
;;
Q N R,Q,C,D,E,W,B,G,H,S,T,U,V,F,L,P,N,J,A S N=$G(N),Q='N,F=Q+Q,P=F+F,W=$L($T(Q))
 S W=$E(W,Q),S='N_+N,W=W-F*S,L=$G(L),R=$C(Q_F_P),R(F)=$C(F+Q_F),R(P)=$C(W-F) W #
 S T=$E($T(Q+F),F,W\S)_$C(W+S+F) X T S B=$P(T,$C(P_P),F),C=B\(W*W),D=B-(C*W*W)\W
 F G=S-Q:F:S+F+Q S E=B-(C*W*W+(D*W)),H=$E($T(Q),G),@H=$S(@H<S:'Q,Q:N)_@H,T=C_D_E
 F A=Q:Q:W\S S J=$E(T,A),C(F)=$S(J>(F+Q)&(J<(S-F)):Q,Q:+N),C(P)=$S(J#F:Q,Q:+N) D
 .S C(Q)=$S(J<(S-F):+N,Q:Q),C(F+Q)=$S(J>Q&(J<(S-F))&(J'=(P+'L))&(J'=(P)):Q,Q:+N)
 .S H('L)=L F  S H(N?.E)=$O(C(H('$G(N)))) Q:H('+L)=L  S F(A,H('L))=C(H(W[(W\S)))
 F U=Q:Q:P W !,R F V=Q:Q:P+F W $S(F(V,U):'Q,Q:$C(P_(W\S))) W:'(V#F) $C('N_F_F+F)
 W !!,R(F)_C_R(P)_D_R(P)_E_R(F) X $RE($E($T(Q),Q+F,P+Q))_R(P)_'N W # G:N=L Q+F Q

It's not only tricky to read but has an attractive form too

Julius Kavay · Aug 31, 2020

First, I think, you should check the above method...
You use the date variable two times

set date = $piece(...)
return date_" "...


I'm pretty shure, if the time in Vienna (Europe) is 00:30:00 then the coresponding UTC time is 23:30:00 previous day (standard time). But you never change the date variable!
As a timestamp:
2020-08-31T00:30:00+01:00 (Vienna, 31. August)
2020-08-30Z23:30:00 (UTC,  30.August)

Second (but this is just my very privete view), checking time(stamp) format should be done BEFORE calling the ConvertW3CToTimestampUTC() method and not in the method itself.

The holy trinity of programming is:
1) accept data (data input)
2) check the data
3) if the data is OK use it, else back to input (or return an error)

If you accpet data without checking, it means, every time, you intend to use those data, you have to check them again and again (as above), wich is not very efficient.

Julius Kavay · Aug 27, 2020

All ISC products (Ensemble, Cache, IRIS...) have an callin and callout interface via dll/so.  As a starting point, read this

https://docs.intersystems.com/healthconnectlatest/csp/docbook/DocBook.UI...

and this

https://cedocs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?K...

You will also need some experience in C/C++ or Delphi or in other language, where you can compile *.dll (Win) or *.so (Linux) files.

See the functions $zf(-3), $zf(-4), $zf(-5) and $zf(-6)

Julius Kavay · Aug 25, 2020

Create a FindLab() method in your ListLabCenter class, something like:

Method FindLab(start = 0, LabId = "", Center = "", Code = "")

{    set nc1=LabId="", nc2=Center="", nc3=Code=""

     for i=start+1:1:..Labs.Count() {

         set tmp=..Labs.GetAt(i)

         if tmp.LabId=LabId!nc1, tmp.Center=Center!nc2, tmp.Code=Code!nc3 return i

}

   quit 0

}

Then use it as follows:

write obj.FindLab(0,"A08829848","A088298480003","") to find a specific Lab

or 

set  center=0
for  { set center = obj.FindLab(center,,"A088298480003")
       quit:'center
       /* do something with center *./
}

to find all LabCenter objects where Center = "A088298480003"

Julius Kavay · Aug 24, 2020

ISO 8601 time format is either yyyy-mm-ddZhh:mm:ss (UTC time) or yyyy-mm-ddThh:mm:ss+TZ (local time)
where TZ is the time zone.

If both times are UTC time, then just compare.
If the times are local times and both times are in the same TZ then just compare
in elsecase either convert both times to UTC or one of the times to the TZ of the another time.
Then just compare.

The compare function is just a $select(), nothing more:

t1, t2 are the times, then

if $select(t1]t2:"t1 later", t1=t2:"equal", 1:"t1 is earlier")

or more general:

set result=$select(t1]t2:1, t1=t2:0, 1:-1)
if result>0 write "t1 is later then t2"
if result>=0 write "t1 is later or equal to t2"
...
Julius Kavay · Jul 29, 2020

I assume,  your JSON is generated by converting a dynamic object to string, i.e.: 

do obj.%ToJSON()

In elsecase, it's created manually an there you could put as many quotes as you like around the numbers.

For the first case, just make a function which converts the numbers into string, see below:

test ;test for stringify
   set a={},a.Name="John",a.Age=47,a.xx="ab:1234",a.City="Boston",a.Year=2020
   set a."Arr"=[11,22,"aa","bb"]
   set a."Obj"={"aa":"bb"}

   write a.%ToJSON(),!
   write $$stringify(a).%ToJSON(),!
   quit

stringify(x)
{
   set y=x.%GetIterator()
   while y.%GetNext(.i,.v) {
     set t=x.%GetTypeOf(i)
     if t="number" { d x.%Set(i,v,"string") } elseif t="array"!(t="object") { do stringify(v) }
   }
   quit x
}

The output  is then:

do ^test
{"Name":"John","Age":47,"xx":"ab:1234","City":"Boston","Year":2020,"Arr":[11,22,"aa","bb"],"Obj":{"aa":"bb"}}
{"Name":"John","Age":"47","xx":"ab:1234","City":"Boston","Year":"2020","Arr":["11","22","aa","bb"],"Obj":{"aa":"bb"}}