Enforce Astropy compatible units

An optional (but default on) checkUnits is added to the constructors of:

- CharacterizeImageTask
- CalibrateTask
- MeasureMergedCoaddSourcesTask

python/lsst/pipe/tasks/calibrate.py

@@ -96,6 +96,11 @@ class CalibrateConfig(pexConfig.Config):
         default = 3,
         doc = "Match radius for matching icSourceCat objects to sourceCat objects (pixels)",
     )
+    checkUnitsParseStrict = pexConfig.Field(
+        doc = "Strictness of Astropy unit compatibility check, can be 'raise', 'warn' or 'silent'",
+        dtype = str,
+        default = "raise",
+    )
 
     def setDefaults(self):
         pexConfig.Config.setDefaults(self)
@@ -269,6 +274,7 @@ def __init__(self, icSourceSchema=None, **kwargs):
         if self.schemaMapper is not None:
             # finalize the schema
             self.schema = self.schemaMapper.getOutputSchema()
+        self.schema.checkUnits(parse_strict=self.config.checkUnitsParseStrict)
 
     @pipeBase.timeMethod
     def run(self, dataRef, exposure=None, background=None, icSourceCat=None, doUnpersist=True):

python/lsst/pipe/tasks/characterizeImage.py

@@ -92,6 +92,11 @@ class CharacterizeImageConfig(pexConfig.Config):
         target = RepairTask,
         doc = "Remove cosmic rays",
     )
+    checkUnitsParseStrict = pexConfig.Field(
+        doc = "Strictness of Astropy unit compatibility check, can be 'raise', 'warn' or 'silent'",
+        dtype = str,
+        default = "raise",
+    )
 
     def setDefaults(self):
         pexConfig.Config.setDefaults(self)
@@ -253,6 +258,7 @@ def __init__(self, schema=None, **kwargs):
         self.makeSubtask("detectAndMeasure", schema=self.schema)
         self._initialFrame = getDebugFrame(self._display, "frame") or 1
         self._frame = self._initialFrame
+        self.schema.checkUnits(parse_strict=self.config.checkUnitsParseStrict)
 
     @pipeBase.timeMethod
     def run(self, dataRef, exposure=None, background=None, doUnpersist=True):

python/lsst/pipe/tasks/multiBand.py

@@ -846,6 +846,11 @@ class MeasureMergedCoaddSourcesConfig(Config):
     doMatchSources = Field(dtype=bool, default=True, doc="Match sources to reference catalog?")
     astrometry = ConfigurableField(target=AstrometryTask, doc="Astrometric matching")
     coaddName = Field(dtype=str, default="deep", doc="Name of coadd")
+    checkUnitsParseStrict = Field(
+        doc = "Strictness of Astropy unit compatibility check, can be 'raise', 'warn' or 'silent'",
+        dtype = str,
+        default = "raise",
+    )
 
     def setDefaults(self):
         Config.setDefaults(self)
@@ -1017,6 +1022,7 @@ def __init__(self, butler=None, schema=None, peakSchema=None, **kwargs):
             self.makeSubtask("astrometry", schema=self.schema)
         if self.config.doPropagateFlags:
             self.makeSubtask("propagateFlags", schema=self.schema)
+        self.schema.checkUnits(parse_strict=self.config.checkUnitsParseStrict)
 
     def run(self, patchRef):
         """!