Set default value for child based on value of parent/primary specimen

Using custom configuration, users can set the default value for the child based on the value of the parent/primary specimen.

Usdecase 1: Set the default value for child level custom field 'Biobank Technician' based on the selection of value at parent/primary specimens level.
"onValueChange": {
          "specimen.extensionDetail.attrsMap.FC15": [
            "function(opts) {",
            "  angular.forEach(opts.viewCtx.spmnCtx.aliquots, ",
            "    function(aliquot) { ",
            "      var user = opts.fns.get(opts.object, opts.field);",
            "      opts.fns.set(aliquot, 'extensionDetail.attrsMap.FC15', user);",
            "    }",
            "  );",

Screenshot when the user selects the 'Biobank Technician' at Parent/Primary specimen level.

Screenshot when Biobank Technician automatically copied from primary/parent specimen level to aliquot level.

Usecase 2: Blank out related fields when updating the value for another field.

 Added the value for TubeType= 'Serum Separator Vacutainer' and assigned the values below two fields.

1. "Cardiac Troponin I (ng/L)" = 'Test Data To Be Blanked' 
2. "Cardiac Troponin T (ng/L)"= 'Test Data To Be Blanked' 
Now I have to edit the specimen and change the 'TubeType' to ='EDTA Vacutainer', the values added for the above two fields get blanked using the below code.
"onValueChange" : {
                 "specimen.collectionEvent.container" : [ 
                  "function(opts) {", 
                    " var container = opts.fns.get(opts.object, opts.field);", 
                    " if (container != 'Serum Separator Vacutainer') {", 
                    " opts.fns.set(opts.object, 'specimen.extensionDetail.attrsMap.ST28', null);", 
                  " opts.fns.set(opts.object, 'specimen.extensionDetail.attrsMap.ST29', null);", 
" }", 
"}" ]