bitbake: hashserv: Support read-only server

The -r/--readonly argument is added to the bitbake-hashserv app. If this
argument is given then clients may only perform read operations against
the server. The read-only mode is implemented by simply not installing
handlers for write operations, this keeps the permission model simple
and reduces the risk of accidentally allowing write operations.

As a sqlite database can be safely opened by multiple processes in
parallel, it's possible to start two hashserv instances against a single
database if you wish to export both a read-only port and a read-write
port.

(Bitbake rev: 492bb02eb0e071c792407ac3113f92492da1a9cc)

Signed-off-by: Paul Barker <pbarker@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/bitbake-hashserv

@@ -33,6 +33,7 @@ def main():
     parser.add_argument('--bind', default=DEFAULT_BIND, help='Bind address (default "%(default)s")')
     parser.add_argument('--database', default='./hashserv.db', help='Database file (default "%(default)s")')
     parser.add_argument('--log', default='WARNING', help='Set logging level')
+    parser.add_argument('-r', '--read-only', action='store_true', help='Disallow write operations from clients')
 
     args = parser.parse_args()
 
@@ -47,7 +48,7 @@ def main():
     console.setLevel(level)
     logger.addHandler(console)
 
-    server = hashserv.create_server(args.bind, args.database)
+    server = hashserv.create_server(args.bind, args.database, read_only=args.read_only)
     server.serve_forever()
     return 0