Merge pull request #4996 from legiongis/cherry_pick_PR_4945_to_master

Cherry pick pr 4945 to master

arches/management/commands/setup_db.py

@@ -137,7 +137,22 @@ def drop_and_recreate_db(self, cursor):
         CONNECTION LIMIT=-1
         TEMPLATE = {};""".format(arches_db['NAME'], arches_db['USER'], arches_db['POSTGIS_TEMPLATE'])
         print(create_query+"\n")
-        cursor.execute(create_query)
+
+        try:
+            cursor.execute(create_query)
+        except psycopg2.ProgrammingError as e:
+            print(e.pgerror)
+            if "template database" in e.pgerror:
+                msg = """It looks like your PostGIS template database is not correctly referenced in
+settings.py/settings_local.py, or it has not yet been created.
+
+To create it, use:
+
+    psql -U {0} -c "CREATE DATABASE {1};"
+    psql -U {0} -d {1} -c "CREATE EXTENSION postgis;"
+""".format(arches_db['USER'], arches_db['POSTGIS_TEMPLATE'])
+                print(msg)
+            exit()
 
     def setup_db(self):
         """