bitbake: bitbake: Rework hash equivalence

Reworks the hash equivalence server to address performance issues that
were encountered with the REST mechanism used previously, particularly
during the heavy request load encountered during signature generation.
Notable changes are:

1) The server protocol is no longer HTTP based. Instead, it uses a
   simpler JSON over a streaming protocol link. This protocol has much
   lower overhead than HTTP since it eliminates the HTTP headers.
2) The hash equivalence server can either bind to a TCP port, or a Unix
   domain socket. Unix domain sockets are more efficient for local
   communication, and so are preferred if the user enables hash
   equivalence only for the local build. The arguments to the
   'bitbake-hashserve' command have been updated accordingly.
3) The value to which BB_HASHSERVE should be set to enable a local hash
   equivalence server is changed to "auto" instead of "localhost:0". The
   latter didn't make sense when the local server was using a Unix
   domain socket.
4) Clients are expected to keep a persistent connection to the server
   instead of creating a new connection each time a request is made for
   optimal performance.
5) Most of the client logic has been moved to the hashserve module in
   bitbake. This makes it easier to share the client code.
6) A new bitbake command has been added called 'bitbake-hashclient'.
   This command can be used to query a hash equivalence server, including
   fetching the statistics and running a performance stress test.
7) The table indexes in the SQLite database have been updated to
   optimize hash lookups. This change is backward compatible, as the
   database will delete the old indexes first if they exist.
8) The server has been reworked to use python async to maximize
   performance with persistently connected clients. This requires Python
   3.5 or later.

(Bitbake rev: 2124eec3a5830afe8e07ffb6f2a0df6a417ac973)

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

1 files changed, 85 insertions, 74 deletions

diff --git a/bitbake/lib/hashserv/tests.py b/bitbake/lib/hashserv/tests.py
index 6845b53884..6584ff57b4 100644
--- a/bitbake/lib/hashserv/tests.py
+++ b/bitbake/lib/hashserv/tests.py
@@ -1,29 +1,40 @@
 #! /usr/bin/env python3
 #
-# Copyright (C) 2018 Garmin Ltd.
+# Copyright (C) 2018-2019 Garmin Ltd.
 #
 # SPDX-License-Identifier: GPL-2.0-only
 #
 
-import unittest
-import multiprocessing
-import sqlite3
+from . import create_server, create_client
 import hashlib
-import urllib.request
-import json
+import logging
+import multiprocessing
+import sys
 import tempfile
-from . import create_server
+import threading
+import unittest
+
+
+class TestHashEquivalenceServer(object):
+    METHOD = 'TestMethod'
+
+    def _run_server(self):
+        # logging.basicConfig(level=logging.DEBUG, filename='bbhashserv.log', filemode='w',
+        #                     format='%(levelname)s %(filename)s:%(lineno)d %(message)s')
+        self.server.serve_forever()
 
-class TestHashEquivalenceServer(unittest.TestCase):
     def setUp(self):
-        # Start a hash equivalence server in the background bound to
-        # an ephemeral port
-        self.dbfile = tempfile.NamedTemporaryFile(prefix="bb-hashserv-db-")
-        self.server = create_server(('localhost', 0), self.dbfile.name)
-        self.server_addr = 'http://localhost:%d' % self.server.socket.getsockname()[1]
-        self.server_thread = multiprocessing.Process(target=self.server.serve_forever)
+        if sys.version_info < (3, 5, 0):
+            self.skipTest('Python 3.5 or later required')
+
+        self.temp_dir = tempfile.TemporaryDirectory(prefix='bb-hashserv')
+        self.dbfile = os.path.join(self.temp_dir.name, 'db.sqlite')
+
+        self.server = create_server(self.get_server_addr(), self.dbfile)
+        self.server_thread = multiprocessing.Process(target=self._run_server)
         self.server_thread.daemon = True
         self.server_thread.start()
+        self.client = create_client(self.server.address)
 
     def tearDown(self):
         # Shutdown server
@@ -31,19 +42,8 @@ class TestHashEquivalenceServer(unittest.TestCase):
         if s is not None:
             self.server_thread.terminate()
             self.server_thread.join()
-
-    def send_get(self, path):
-        url = '%s/%s' % (self.server_addr, path)
-        request = urllib.request.Request(url)
-        response = urllib.request.urlopen(request)
-        return json.loads(response.read().decode('utf-8'))
-
-    def send_post(self, path, data):
-        headers = {'content-type': 'application/json'}
-        url = '%s/%s' % (self.server_addr, path)
-        request = urllib.request.Request(url, json.dumps(data).encode('utf-8'), headers)
-        response = urllib.request.urlopen(request)
-        return json.loads(response.read().decode('utf-8'))
+        self.client.close()
+        self.temp_dir.cleanup()
 
     def test_create_hash(self):
         # Simple test that hashes can be created
@@ -51,16 +51,11 @@ class TestHashEquivalenceServer(unittest.TestCase):
         outhash = '2765d4a5884be49b28601445c2760c5f21e7e5c0ee2b7e3fce98fd7e5970796f'
         unihash = 'f46d3fbb439bd9b921095da657a4de906510d2cd'
 
-        d = self.send_get('v1/equivalent?method=TestMethod&taskhash=%s' % taskhash)
-        self.assertIsNone(d, msg='Found unexpected task, %r' % d)
+        result = self.client.get_unihash(self.METHOD, taskhash)
+        self.assertIsNone(result, msg='Found unexpected task, %r' % result)
 
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash,
-            'method': 'TestMethod',
-            'outhash': outhash,
-            'unihash': unihash,
-            })
-        self.assertEqual(d['unihash'], unihash, 'Server returned bad unihash')
+        result = self.client.report_unihash(taskhash, self.METHOD, outhash, unihash)
+        self.assertEqual(result['unihash'], unihash, 'Server returned bad unihash')
 
     def test_create_equivalent(self):
         # Tests that a second reported task with the same outhash will be
@@ -68,25 +63,16 @@ class TestHashEquivalenceServer(unittest.TestCase):
         taskhash = '53b8dce672cb6d0c73170be43f540460bfc347b4'
         outhash = '5a9cb1649625f0bf41fc7791b635cd9c2d7118c7f021ba87dcd03f72b67ce7a8'
         unihash = 'f37918cc02eb5a520b1aff86faacbc0a38124646'
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash,
-            'method': 'TestMethod',
-            'outhash': outhash,
-            'unihash': unihash,
-            })
-        self.assertEqual(d['unihash'], unihash, 'Server returned bad unihash')
+
+        result = self.client.report_unihash(taskhash, self.METHOD, outhash, unihash)
+        self.assertEqual(result['unihash'], unihash, 'Server returned bad unihash')
 
         # Report a different task with the same outhash. The returned unihash
         # should match the first task
         taskhash2 = '3bf6f1e89d26205aec90da04854fbdbf73afe6b4'
         unihash2 = 'af36b199320e611fbb16f1f277d3ee1d619ca58b'
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash2,
-            'method': 'TestMethod',
-            'outhash': outhash,
-            'unihash': unihash2,
-            })
-        self.assertEqual(d['unihash'], unihash, 'Server returned bad unihash')
+        result = self.client.report_unihash(taskhash2, self.METHOD, outhash, unihash2)
+        self.assertEqual(result['unihash'], unihash, 'Server returned bad unihash')
 
     def test_duplicate_taskhash(self):
         # Tests that duplicate reports of the same taskhash with different
@@ -95,38 +81,63 @@ class TestHashEquivalenceServer(unittest.TestCase):
         taskhash = '8aa96fcffb5831b3c2c0cb75f0431e3f8b20554a'
         outhash = 'afe240a439959ce86f5e322f8c208e1fedefea9e813f2140c81af866cc9edf7e'
         unihash = '218e57509998197d570e2c98512d0105985dffc9'
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash,
-            'method': 'TestMethod',
-            'outhash': outhash,
-            'unihash': unihash,
-            })
+        self.client.report_unihash(taskhash, self.METHOD, outhash, unihash)
 
-        d = self.send_get('v1/equivalent?method=TestMethod&taskhash=%s' % taskhash)
-        self.assertEqual(d['unihash'], unihash)
+        result = self.client.get_unihash(self.METHOD, taskhash)
+        self.assertEqual(result, unihash)
 
         outhash2 = '0904a7fe3dc712d9fd8a74a616ddca2a825a8ee97adf0bd3fc86082c7639914d'
         unihash2 = 'ae9a7d252735f0dafcdb10e2e02561ca3a47314c'
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash,
-            'method': 'TestMethod',
-            'outhash': outhash2,
-            'unihash': unihash2
-            })
+        self.client.report_unihash(taskhash, self.METHOD, outhash2, unihash2)
 
-        d = self.send_get('v1/equivalent?method=TestMethod&taskhash=%s' % taskhash)
-        self.assertEqual(d['unihash'], unihash)
+        result = self.client.get_unihash(self.METHOD, taskhash)
+        self.assertEqual(result, unihash)
 
         outhash3 = '77623a549b5b1a31e3732dfa8fe61d7ce5d44b3370f253c5360e136b852967b4'
         unihash3 = '9217a7d6398518e5dc002ed58f2cbbbc78696603'
-        d = self.send_post('v1/equivalent', {
-            'taskhash': taskhash,
-            'method': 'TestMethod',
-            'outhash': outhash3,
-            'unihash': unihash3
-            })
+        self.client.report_unihash(taskhash, self.METHOD, outhash3, unihash3)
+
+        result = self.client.get_unihash(self.METHOD, taskhash)
+        self.assertEqual(result, unihash)
+
+    def test_stress(self):
+        def query_server(failures):
+            client = Client(self.server.address)
+            try:
+                for i in range(1000):
+                    taskhash = hashlib.sha256()
+                    taskhash.update(str(i).encode('utf-8'))
+                    taskhash = taskhash.hexdigest()
+                    result = client.get_unihash(self.METHOD, taskhash)
+                    if result != taskhash:
+                        failures.append("taskhash mismatch: %s != %s" % (result, taskhash))
+            finally:
+                client.close()
+
+        # Report hashes
+        for i in range(1000):
+            taskhash = hashlib.sha256()
+            taskhash.update(str(i).encode('utf-8'))
+            taskhash = taskhash.hexdigest()
+            self.client.report_unihash(taskhash, self.METHOD, taskhash, taskhash)
+
+        failures = []
+        threads = [threading.Thread(target=query_server, args=(failures,)) for t in range(100)]
+
+        for t in threads:
+            t.start()
+
+        for t in threads:
+            t.join()
+
+        self.assertFalse(failures)
+
 
-        d = self.send_get('v1/equivalent?method=TestMethod&taskhash=%s' % taskhash)
-        self.assertEqual(d['unihash'], unihash)
+class TestHashEquivalenceUnixServer(TestHashEquivalenceServer, unittest.TestCase):
+    def get_server_addr(self):
+        return "unix://" + os.path.join(self.temp_dir.name, 'sock')
 
 
+class TestHashEquivalenceTCPServer(TestHashEquivalenceServer, unittest.TestCase):
+    def get_server_addr(self):
+        return "localhost:0"