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/lib/hashserv/tests.py

@@ -6,6 +6,7 @@
 #
 
 from . import create_server, create_client
+from .client import HashConnectionError
 import hashlib
 import logging
 import multiprocessing
@@ -29,7 +30,7 @@ class HashEquivalenceTestSetup(object):
 
     server_index = 0
 
-    def start_server(self, dbpath=None, upstream=None):
+    def start_server(self, dbpath=None, upstream=None, read_only=False):
         self.server_index += 1
         if dbpath is None:
             dbpath = os.path.join(self.temp_dir.name, "db%d.sqlite" % self.server_index)
@@ -38,7 +39,10 @@ class HashEquivalenceTestSetup(object):
             thread.terminate()
             thread.join()
 
-        server = create_server(self.get_server_addr(self.server_index), dbpath, upstream=upstream)
+        server = create_server(self.get_server_addr(self.server_index),
+                               dbpath,
+                               upstream=upstream,
+                               read_only=read_only)
         server.dbpath = dbpath
 
         server.thread = multiprocessing.Process(target=_run_server, args=(server, self.server_index))
@@ -242,6 +246,31 @@ class HashEquivalenceCommonTests(object):
         self.assertClientGetHash(side_client, taskhash4, unihash4)
         self.assertClientGetHash(self.client, taskhash4, None)
 
+    def test_ro_server(self):
+        (ro_client, ro_server) = self.start_server(dbpath=self.server.dbpath, read_only=True)
+
+        # Report a hash via the read-write server
+        taskhash = '35788efcb8dfb0a02659d81cf2bfd695fb30faf9'
+        outhash = '2765d4a5884be49b28601445c2760c5f21e7e5c0ee2b7e3fce98fd7e5970796f'
+        unihash = 'f46d3fbb439bd9b921095da657a4de906510d2cd'
+
+        result = self.client.report_unihash(taskhash, self.METHOD, outhash, unihash)
+        self.assertEqual(result['unihash'], unihash, 'Server returned bad unihash')
+
+        # Check the hash via the read-only server
+        self.assertClientGetHash(ro_client, taskhash, unihash)
+
+        # Ensure that reporting via the read-only server fails
+        taskhash2 = 'c665584ee6817aa99edfc77a44dd853828279370'
+        outhash2 = '3c979c3db45c569f51ab7626a4651074be3a9d11a84b1db076f5b14f7d39db44'
+        unihash2 = '90e9bc1d1f094c51824adca7f8ea79a048d68824'
+
+        with self.assertRaises(HashConnectionError):
+            ro_client.report_unihash(taskhash2, self.METHOD, outhash2, unihash2)
+
+        # Ensure that the database was not modified
+        self.assertClientGetHash(self.client, taskhash2, None)
+
 
 class TestHashEquivalenceUnixServer(HashEquivalenceTestSetup, HashEquivalenceCommonTests, unittest.TestCase):
     def get_server_addr(self, server_idx):