Add CordaRPCOps.notaryPartyFromX500Name (#1786)

core/src/main/kotlin/net/corda/core/messaging/CordaRPCOps.kt

@@ -256,6 +256,14 @@ interface CordaRPCOps : RPCOps {
     /** Returns the [Party] with the X.500 principal as it's [Party.name]. */
     fun wellKnownPartyFromX500Name(x500Name: CordaX500Name): Party?
 
+    /**
+     * Get a notary identity by name.
+     *
+     * @return the notary identity, or null if there is no notary by that name. Note that this will return null if there
+     * is a peer with that name but they are not a recognised notary service.
+     */
+    fun notaryPartyFromX500Name(x500Name: CordaX500Name): Party?
+
     /**
      * Returns a list of candidate matches for a given string, with optional fuzzy(ish) matching. Fuzzy matching may
      * get smarter with time e.g. to correct spelling errors, so you should not hard-code indexes into the results

node/src/main/kotlin/net/corda/node/internal/CordaRPCOpsImpl.kt

@@ -200,6 +200,8 @@ class CordaRPCOpsImpl(
         }
     }
 
+    override fun notaryPartyFromX500Name(x500Name: CordaX500Name): Party? = services.networkMapCache.getNotary(x500Name)
+
     override fun partiesFromName(query: String, exactMatch: Boolean): Set<Party> {
         return database.transaction {
             services.identityService.partiesFromName(query, exactMatch)