Define GeometryBackend for DD4Hep and DetDesc and use DataType=2024/Run3 when DetDesc is picked up from Run2Support

• Issue: As https://lhcb-nightlies.web.cern.ch/nightly/lhcb-sim11-run5/10/Gauss/x86_64_v2-el9-gcc12-opt/tests showned, all dd4hep tests are failred as they are trying to access git:///Conditions/Online/valid_runs.txt. It is unreasonable because DD4hep does not use conditions.

• Reason: In LHCb, UseDD4Hep is a compile time constant, while in Gauss it is decided at runtime.

• Solution: DDDB should be removed form Run2Support, keep it only at LHCb, but it will take a long time to implement as some Gauss/Gaussion tasks are still rely on that. And this issue is blocking the progress of DD4hep related work, especially blocking the merge request for Upgrade2 new sub-detector's merge requst in Detector (we can not test them). A kind of temporary solution is introduce a new properties, Geometrybackend, for the Geometry.

• Another change: Use DataType=2024/Run3 when DetDesc is picked up from Run2Support

Work with Run2Support!58 (merged) and Gauss!1056 (merged)

Includes !4388 (closed)

@gcorti @clemenci

Det/DDDB/python/DDDB/Configuration.py

@@ -24,11 +24,6 @@ from datetime import datetime, timedelta
 from DDDB.CheckDD4Hep import UseDD4Hep
 from Gaudi.Configuration import *
 
-if not UseDD4Hep:
-    from DetCond.Configuration import CondDB
-    from Configurables import (XmlCnvSvc, XmlParserSvc,
-                               EntityResolverDispatcher, GitEntityResolver)
-
 GIT_CONDDBS = {}
 
 
@@ -95,6 +90,8 @@ class DDDBConf(ConfigurableUser):
         "run3/trunk",
         "GeometryMain":
         "LHCb.xml",
+        "GeometryBackend":
+        "DD4Hep" if UseDD4Hep else "DetDesc",
         "ConditionsLocation":
         "",
         "DD4HepDetectorList": [
@@ -108,7 +105,7 @@ class DDDBConf(ConfigurableUser):
         'DbRoot':
         """ Root file of the detector description """,
         'DataType':
-        """ Symbolic name for the data type. Allowed values: ["2023", "2022", "2018", "2017", "2016", "2015", "2013", "2012", "2011", "2010", "2009","2008","Upgrade"] """,
+        """ Symbolic name for the data type. Allowed values: ["2024", "2023", "2022", "2018", "2017", "2016", "2015", "2013", "2012", "2011", "2010", "2009", "2008", "Run3", "Upgrade"] """,
         'Simulation':
         """ Boolean flag to select the simulation or real-data configuration """,
         'InitialTime':
@@ -125,23 +122,34 @@ class DDDBConf(ConfigurableUser):
         """ Version of the DD4hep geometry that should be used """,
         'GeometryMain':
         """ Main compact file to be loaded """,
+        'GeometryBackend':
+        """ Backend to be used for the geometry, must be DD4Hep or DetDesc """,
         'ConditionsLocation':
         "Location of the conditions repository (lookup from CMAKE_PREFIX_PATH if not specified)",
         'ConditionsVersion':
         """ Tag for the conditions database """,
     }
 
-    __used_configurables__ = [] if UseDD4Hep else [CondDB]
-
     def __apply_configuration__(self):
         """
         Converts the high-level information passed as properties into low-level configuration.
         """
+        assert self.getProp("GeometryBackend") in (
+            "DetDesc",
+            "DD4Hep"), "GeometryBackend has to be one of 'DetDesc' or 'DD4Hep'"
+        backend = self.getProp("GeometryBackend")
+        if backend == "DetDesc":
+            from DetCond.Configuration import CondDB
+            from Configurables import (XmlCnvSvc, XmlParserSvc,
+                                       EntityResolverDispatcher,
+                                       GitEntityResolver)
+            __used_configurables__ = [CondDB]
         ##########################################################################
         # DD4hep Detector Configuration
         ##########################################################################
         ##########################################################################
-        if UseDD4Hep:
+        elif backend == "DD4Hep":
+            __used_configurables__ = []
             from Configurables import LHCb__Det__LbDD4hep__DD4hepSvc as DD4hepSvc
             dd4hepSvc = DD4hepSvc()
 
@@ -311,7 +319,8 @@ class DDDBConf(ConfigurableUser):
         # by default, use the latest DQFLAGS tag for the requested data type
         # (unless already set by a data type handler)
         if not self.getProp("Simulation") and dataType not in ("Upgrade",
-                                                               "2022", "2023"):
+                                                               "2022", "2023",
+                                                               "2024", "Run3"):
             self.__set_tag__(["DQFLAGS"], "<latest:{0}>".format(dataType))
 
         # Get particle properties table from condDB
@@ -379,6 +388,13 @@ class DDDBConf(ConfigurableUser):
                 "EventClockSvc().InitialTime already set to %s UTC (requested %s UTC)",
                 t.isoformat(), utcDatetime.isoformat())
 
+    def __2024_conf__(self):
+        """
+        Default configuration for 2024 data
+        to be updated after final configuration is taken
+        """
+        pass
+
     def __2023_conf__(self):
         """
         Default configuration for 2023 data
@@ -513,6 +529,12 @@ class DDDBConf(ConfigurableUser):
         else:
             self.__set_tag__(["SIMCOND"], "sim-20090212")
 
+    def __Run3_conf__(self):
+        """
+        Default database for Run3 MonteCarlo production and analysis
+        """
+        pass  # nothing special here
+
     def __Upgrade_conf__(self):
         """
         Default database for Upgrade MonteCarlo production and analysis
@@ -520,6 +542,7 @@ class DDDBConf(ConfigurableUser):
         pass  # nothing special here
 
     __data_types_handlers__ = {
+        "2024": __2024_conf__,
         "2023": __2023_conf__,
         "2022": __2022_conf__,
         "2018": __2018_conf__,
@@ -532,5 +555,6 @@ class DDDBConf(ConfigurableUser):
         "2010": __2010_conf__,
         "2009": __2009_conf__,
         "2008": __2008_conf__,
+        "Run3": __Run3_conf__,
         "Upgrade": __Upgrade_conf__
     }