misc: truncate schema_temp to 63 characters (#43165)

wcs_olap/feeder.py

@@ -20,6 +20,17 @@ psycopg2.extensions.register_type(psycopg2.extensions.UNICODE)
 psycopg2.extensions.register_type(psycopg2.extensions.UNICODEARRAY)
 
 
+def truncate_pg_identifier(identifier, hash_length=6, force_hash=False):
+    if len(identifier) < 64 and not force_hash:
+        return identifier
+    else:
+        # insert hash in the middle, to keep some readability
+        return (
+            identifier[:(63 - hash_length) // 2]
+            + hashlib.md5(identifier.encode('utf-8')).hexdigest()[:hash_length]
+            + identifier[-(63 - hash_length) // 2:])
+
+
 def quote(name):
     return '"%s"' % name
 
@@ -79,7 +90,7 @@ class WcsOlapFeeder(object):
         self.ctx = Context()
         self.ctx.push({
             'schema': self.schema,
-            'schema_temp': self.schema + '_temp',
+            'schema_temp': truncate_pg_identifier(schema + '_temp'),
             'role_table': 'role',
             'channel_table': 'channel',
             'category_table': 'category',