Given an instance identifier like:
"/network-topology:network-topology/network-topology:topology/network-topology:topology[network-topology:topology-id='ovsdb:1']/network-topology:node/network-topology:node[network-topology:node-id='ovsdb://127.0.0.1:16640']"

Submitted via restconf, restconf fails to properly deserialize it (instead simple writing a null in the field containing that value).

Some preliminary debugging showed that in controller/opendaylight/md-sal/sal-rest-connector/src/main/java/org/opendaylight/controller/sal/rest/impl/RestUtil.java

what is going wrong is that on line 41 (in method asInstanceIdentifier()):

final String[] xPathParts = valueTrimmed.split("/");

This results in splitting the xpath expression mid-predicate: because the predicate:[network-topology:node-id='ovsdb://127.0.0.1:16640']

contains a number of "/" characters within the literal 'ovsdb://127.0.0.1:16640' it contains.

Looking at the XPath BNF:

http://www.w3.org/2002/11/xquery-xpath-applets/xpath-bnf.html

It appears that it is valid to have a "/" within a literal (which in this case it is.

Please fix the parsing to correctly handle string literals.