Update class-keys.rst

docs/webapp/properties/class-keys.rst

@@ -5,4 +5,16 @@ Specify keys for the classes in your data model by adding them to the `class_key
 
 Keys defined in the `class_keys.properties` file are also used to boost the search visibility of their associated classes.
 
+The `class_keys.properties` file specifies the keys used to generate the permanent navigable URL which is used in the "SHARE" button in the report pages. If not specified, the primaryidentifier key is used.
+
+=============== ================
+key             value
+=============== ================
+Protein_URI     primaryAccession
+Organism_URI    taxonId
+Publication_URI pubMedId
+=============== ================
+
+Given the above configuration, in FlyMine, the URL of the report page for the protein ARRB_DROME, with UniProt accession P19107, will be http://flymine.org/protein:P19107.
+
 .. index:: class keys, list upload classes