DM-10319: _filename functions return first mappable repository even when file does not exist

python/lsst/daf/persistence/butler.py

@@ -1536,6 +1536,56 @@ def dataRef(self, datasetType, level=None, dataId={}, **rest):
                                (str(datasetType), str(level), str(dataId), str(rest)))
         return ButlerDataRef(subset, subset.cache[0])
 
+    def getUri(self, datasetType, dataId=None, write=False, **rest):
+        """Return the URI for a dataset
+
+        .. warning:: This is intended only for debugging. The URI should
+        never be used for anything other than printing.
+
+        .. note:: In the event there are multiple URIs for read, we return only
+        the first.
+
+        .. note:: getUri() does not currently support composite datasets.
+
+        Parameters
+        ----------
+        datasetType : `str`
+           The dataset type of interest.
+        dataId : `dict`, optional
+           The data identifier.
+        write : `bool`, optional
+           Return the URI for writing?
+        rest : `dict`, optional
+           Keyword arguments for the data id.
+
+        Returns
+        -------
+        uri : `str`
+           URI for dataset.
+        """
+        datasetType = self._resolveDatasetTypeAlias(datasetType)
+        dataId = DataId(dataId)
+        dataId.update(**rest)
+        locations = self._locate(datasetType, dataId, write=write)
+        if locations is None:
+            raise NoResults("No locations for getUri: ", datasetType, dataId)
+
+        if write:
+            # Follow the write path
+            # Return the first valid write location.
+            for location in locations:
+                if isinstance(location, ButlerComposite):
+                    for name, info in location.componentInfo.items():
+                        if not info.inputOnly:
+                            return self.getUri(info.datasetType, location.dataId, write=True)
+                else:
+                    return location.getLocationsWithRoot()[0]
+            # fall back to raise
+            raise NoResults("No locations for getUri(write=True): ", datasetType, dataId)
+        else:
+            # Follow the read path, only return the first valid read
+            return locations.getLocationsWithRoot()[0]
+
     def _read(self, location):
         """Unpersist an object using data inside a ButlerLocation or ButlerComposite object.
 

python/lsst/daf/persistence/butlerSubset.py

@@ -215,6 +215,36 @@ def put(self, obj, datasetType=None, doBackup=False, **rest):
             datasetType = self.butlerSubset.datasetType
         self.butlerSubset.butler.put(obj, datasetType, self.dataId, doBackup=doBackup, **rest)
 
+    def getUri(self, datasetType=None, write=False, **rest):
+        """Return the URL for a dataset
+
+        .. warning:: This is intended only for debugging. The URI should
+        never be used for anything other than printing.
+
+        .. note:: In the event there are multiple URIs, we return only
+        the first.
+
+        .. note:: getUri() does not currently support composite datasets.
+
+        Parameters
+        ----------
+        datasetType : `str`, optional
+           The dataset type of interest.
+        write : `bool`, optional
+           Return the URI for writing?
+        rest : `dict`, optional
+           Keyword arguments for the data id.
+
+        Returns
+        -------
+        uri : `str`
+           URI for dataset
+        """
+
+        if datasetType is None:
+            datasetType = self.butlerSubset.datasetType
+        return self.butlerSubset.butler.getUri(datasetType, self.dataId, write=write, **rest)
+
     def subLevels(self):
         """
         Return a list of the lower levels of the hierarchy than this

tests/test_butlerSubset.py

@@ -144,6 +144,12 @@ def testSingleIteration(self):
             self.assertEqual(type(image), list)
             self.assertEqual(image, inputList)
 
+            # Tests for new getUri
+            imageUri = iterator.getUri(self.calexpTypeName)
+            fileName = 'calexp_v%(visit)d_R%(raft)s_S%(sensor)s.pickle' % iterator.dataId
+            self.assertEqual(imageUri, os.path.join(self.tmpRoot, fileName))
+            self.assertEqual(os.path.isfile(imageUri), True)
+
         for fileName in inputList:
             os.unlink(os.path.join(self.tmpRoot, fileName))
 

tests/test_repository.py

@@ -172,6 +172,18 @@ def testGet(self):
         # in this case the width is known to be 1026:
         self.assertEqual(raw_image[1].header["NAXIS1"], 1026)
 
+    def testGetUri(self):
+        raw_uri = self.butler.getUri('raw', {'visit': '2', 'filter': 'g'})
+        self.assertEqual(raw_uri,
+                         os.path.join(ROOT, 'butlerAlias', 'data', 'input', 'raw', 'raw_v2_fg.fits.gz'))
+        self.assertEqual(os.path.isfile(raw_uri), True)
+
+    def testGetUriWrite(self):
+        raw_uri = self.butler.getUri('raw', {'visit': '9', 'filter': 'g'}, write=True)
+        self.assertEqual(raw_uri,
+                         os.path.join(self.testDir, 'repoA', 'raw', 'raw_v9_fg.fits.gz'))
+        self.assertEqual(os.path.isfile(raw_uri), False)
+
     def testSubset(self):
         subset = self.butler.subset('raw')
         self.assertEqual(len(subset), 3)