bitbake: hashserv: Add unihash-exists API

Adds API to check if the server is aware of the existence of a given
unihash. This can be used as an optimization for sstate where a client
can query the hash equivalence server to check if a unihash exists
before querying the sstate cache. If the hash server isn't aware of the
existence of a unihash, then there is very likely not a matching sstate
object, so this should be able to significantly cut down on the number
of negative hits on the sstate cache.

(Bitbake rev: cfe0ac071cfb998e4a1dd263f8860b140843361a)

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/bitbake-hashclient

@@ -217,6 +217,14 @@ def main():
         print("Removed %d rows" % result["count"])
         return 0
 
+    def handle_unihash_exists(args, client):
+        result = client.unihash_exists(args.unihash)
+        if args.quiet:
+            return 0 if result else 1
+
+        print("true" if result else "false")
+        return 0
+
     parser = argparse.ArgumentParser(description='Hash Equivalence Client')
     parser.add_argument('--address', default=DEFAULT_ADDRESS, help='Server address (default "%(default)s")')
     parser.add_argument('--log', default='WARNING', help='Set logging level')
@@ -309,6 +317,11 @@ def main():
     gc_sweep_parser.add_argument("mark", help="Mark for this garbage collection operation")
     gc_sweep_parser.set_defaults(func=handle_gc_sweep)
 
+    unihash_exists_parser = subparsers.add_parser('unihash-exists', help="Check if a unihash is known to the server")
+    unihash_exists_parser.add_argument("--quiet", action="store_true", help="Don't print status. Instead, exit with 0 if unihash exists and 1 if it does not")
+    unihash_exists_parser.add_argument("unihash", help="Unihash to check")
+    unihash_exists_parser.set_defaults(func=handle_unihash_exists)
+
     args = parser.parse_args()
 
     logger = logging.getLogger('hashserv')