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.

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

5 files changed, 138 insertions, 33 deletions

diff --git a/lib/hashserv/client.py b/lib/hashserv/client.py
index e6dc41791..daf1e1284 100644
--- a/lib/hashserv/client.py
+++ b/lib/hashserv/client.py
@@ -16,6 +16,7 @@ logger = logging.getLogger("hashserv.client")
 class AsyncClient(bb.asyncrpc.AsyncClient):
     MODE_NORMAL = 0
     MODE_GET_STREAM = 1
+    MODE_EXIST_STREAM = 2
 
     def __init__(self, username=None, password=None):
         super().__init__("OEHASHEQUIV", "1.1", logger)
@@ -49,19 +50,36 @@ class AsyncClient(bb.asyncrpc.AsyncClient):
             await self.socket.send("END")
             return await self.socket.recv()
 
-        if new_mode == self.MODE_NORMAL and self.mode == self.MODE_GET_STREAM:
+        async def normal_to_stream(command):
+            r = await self.invoke({command: None})
+            if r != "ok":
+                raise ConnectionError(
+                    f"Unable to transition to stream mode: Bad response from server {r!r}"
+                )
+
+            self.logger.debug("Mode is now %s", command)
+
+        if new_mode == self.mode:
+            return
+
+        self.logger.debug("Transitioning mode %s -> %s", self.mode, new_mode)
+
+        # Always transition to normal mode before switching to any other mode
+        if self.mode != self.MODE_NORMAL:
             r = await self._send_wrapper(stream_to_normal)
             if r != "ok":
                 self.check_invoke_error(r)
-                raise ConnectionError("Unable to transition to normal mode: Bad response from server %r" % r)
-        elif new_mode == self.MODE_GET_STREAM and self.mode == self.MODE_NORMAL:
-            r = await self.invoke({"get-stream": None})
-            if r != "ok":
-                raise ConnectionError("Unable to transition to stream mode: Bad response from server %r" % r)
-        elif new_mode != self.mode:
-            raise Exception(
-                "Undefined mode transition %r -> %r" % (self.mode, new_mode)
-            )
+                raise ConnectionError(
+                    f"Unable to transition to normal mode: Bad response from server {r!r}"
+                )
+            self.logger.debug("Mode is now normal")
+
+        if new_mode == self.MODE_GET_STREAM:
+            await normal_to_stream("get-stream")
+        elif new_mode == self.MODE_EXIST_STREAM:
+            await normal_to_stream("exists-stream")
+        elif new_mode != self.MODE_NORMAL:
+            raise Exception("Undefined mode transition {self.mode!r} -> {new_mode!r}")
 
         self.mode = new_mode
 
@@ -95,6 +113,11 @@ class AsyncClient(bb.asyncrpc.AsyncClient):
             {"get": {"taskhash": taskhash, "method": method, "all": all_properties}}
         )
 
+    async def unihash_exists(self, unihash):
+        await self._set_mode(self.MODE_EXIST_STREAM)
+        r = await self.send_stream(unihash)
+        return r == "true"
+
     async def get_outhash(self, method, outhash, taskhash, with_unihash=True):
         await self._set_mode(self.MODE_NORMAL)
         return await self.invoke(
@@ -236,6 +259,7 @@ class Client(bb.asyncrpc.Client):
             "report_unihash",
             "report_unihash_equiv",
             "get_taskhash",
+            "unihash_exists",
             "get_outhash",
             "get_stats",
             "reset_stats",
diff --git a/lib/hashserv/server.py b/lib/hashserv/server.py
index 5ed852d1f..68f64f983 100644
--- a/lib/hashserv/server.py
+++ b/lib/hashserv/server.py
@@ -234,6 +234,7 @@ class ServerClient(bb.asyncrpc.AsyncServerConnection):
                 "get": self.handle_get,
                 "get-outhash": self.handle_get_outhash,
                 "get-stream": self.handle_get_stream,
+                "exists-stream": self.handle_exists_stream,
                 "get-stats": self.handle_get_stats,
                 "get-db-usage": self.handle_get_db_usage,
                 "get-db-query-columns": self.handle_get_db_query_columns,
@@ -377,8 +378,7 @@ class ServerClient(bb.asyncrpc.AsyncServerConnection):
         await self.db.insert_unihash(data["method"], data["taskhash"], data["unihash"])
         await self.db.insert_outhash(data)
 
-    @permissions(READ_PERM)
-    async def handle_get_stream(self, request):
+    async def _stream_handler(self, handler):
         await self.socket.send_message("ok")
 
         while True:
@@ -400,35 +400,50 @@ class ServerClient(bb.asyncrpc.AsyncServerConnection):
                 if l == "END":
                     break
 
-                (method, taskhash) = l.split()
-                # self.logger.debug('Looking up %s %s' % (method, taskhash))
-                row = await self.db.get_equivalent(method, taskhash)
-
-                if row is not None:
-                    msg = row["unihash"]
-                    # self.logger.debug('Found equivalent task %s -> %s', (row['taskhash'], row['unihash']))
-                elif self.upstream_client is not None:
-                    upstream = await self.upstream_client.get_unihash(method, taskhash)
-                    if upstream:
-                        msg = upstream
-                    else:
-                        msg = ""
-                else:
-                    msg = ""
-
+                msg = await handler(l)
                 await self.socket.send(msg)
             finally:
                 request_measure.end()
                 self.request_sample.end()
 
-            # Post to the backfill queue after writing the result to minimize
-            # the turn around time on a request
-            if upstream is not None:
-                await self.server.backfill_queue.put((method, taskhash))
-
         await self.socket.send("ok")
         return self.NO_RESPONSE
 
+    @permissions(READ_PERM)
+    async def handle_get_stream(self, request):
+        async def handler(l):
+            (method, taskhash) = l.split()
+            # self.logger.debug('Looking up %s %s' % (method, taskhash))
+            row = await self.db.get_equivalent(method, taskhash)
+
+            if row is not None:
+                # self.logger.debug('Found equivalent task %s -> %s', (row['taskhash'], row['unihash']))
+                return row["unihash"]
+
+            if self.upstream_client is not None:
+                upstream = await self.upstream_client.get_unihash(method, taskhash)
+                if upstream:
+                    await self.server.backfill_queue.put((method, taskhash))
+                    return upstream
+
+            return ""
+
+        return await self._stream_handler(handler)
+
+    @permissions(READ_PERM)
+    async def handle_exists_stream(self, request):
+        async def handler(l):
+            if await self.db.unihash_exists(l):
+                return "true"
+
+            if self.upstream_client is not None:
+                if await self.upstream_client.unihash_exists(l):
+                    return "true"
+
+            return "false"
+
+        return await self._stream_handler(handler)
+
     async def report_readonly(self, data):
         method = data["method"]
         outhash = data["outhash"]
diff --git a/lib/hashserv/sqlalchemy.py b/lib/hashserv/sqlalchemy.py
index 873547809..0e28d738f 100644
--- a/lib/hashserv/sqlalchemy.py
+++ b/lib/hashserv/sqlalchemy.py
@@ -48,6 +48,7 @@ class UnihashesV3(Base):
     __table_args__ = (
         UniqueConstraint("method", "taskhash"),
         Index("taskhash_lookup_v4", "method", "taskhash"),
+        Index("unihash_lookup_v1", "unihash"),
     )
 
 
@@ -279,6 +280,16 @@ class Database(object):
             )
             return map_row(result.first())
 
+    async def unihash_exists(self, unihash):
+        async with self.db.begin():
+            result = await self._execute(
+                select(UnihashesV3)
+                .where(UnihashesV3.unihash == unihash)
+                .limit(1)
+            )
+
+            return result.first() is not None
+
     async def get_outhash(self, method, outhash):
         async with self.db.begin():
             result = await self._execute(
diff --git a/lib/hashserv/sqlite.py b/lib/hashserv/sqlite.py
index 608490730..da2e844a0 100644
--- a/lib/hashserv/sqlite.py
+++ b/lib/hashserv/sqlite.py
@@ -145,6 +145,9 @@ class DatabaseEngine(object):
                 "CREATE INDEX IF NOT EXISTS taskhash_lookup_v4 ON unihashes_v3 (method, taskhash)"
             )
             cursor.execute(
+                "CREATE INDEX IF NOT EXISTS unihash_lookup_v1 ON unihashes_v3 (unihash)"
+            )
+            cursor.execute(
                 "CREATE INDEX IF NOT EXISTS outhash_lookup_v3 ON outhashes_v2 (method, outhash)"
             )
             cursor.execute("CREATE INDEX IF NOT EXISTS config_lookup ON config (name)")
@@ -255,6 +258,19 @@ class Database(object):
             )
             return cursor.fetchone()
 
+    async def unihash_exists(self, unihash):
+        with closing(self.db.cursor()) as cursor:
+            cursor.execute(
+                """
+                SELECT * FROM unihashes_v3 WHERE unihash=:unihash
+                LIMIT 1
+                """,
+                {
+                    "unihash": unihash,
+                },
+            )
+            return cursor.fetchone() is not None
+
     async def get_outhash(self, method, outhash):
         with closing(self.db.cursor()) as cursor:
             cursor.execute(
diff --git a/lib/hashserv/tests.py b/lib/hashserv/tests.py
index aeedab357..fbbe81512 100644
--- a/lib/hashserv/tests.py
+++ b/lib/hashserv/tests.py
@@ -442,6 +442,11 @@ class HashEquivalenceCommonTests(object):
         self.assertEqual(result['taskhash'], taskhash9, 'Server failed to copy unihash from upstream')
         self.assertEqual(result['method'], self.METHOD)
 
+    def test_unihash_exsits(self):
+        taskhash, outhash, unihash = self.create_test_hash(self.client)
+        self.assertTrue(self.client.unihash_exists(unihash))
+        self.assertFalse(self.client.unihash_exists('6662e699d6e3d894b24408ff9a4031ef9b038ee8'))
+
     def test_ro_server(self):
         rw_server = self.start_server()
         rw_client = self.start_client(rw_server.address)
@@ -1031,6 +1036,40 @@ class TestHashEquivalenceClient(HashEquivalenceTestSetup, unittest.TestCase):
     def test_stress(self):
         self.run_hashclient(["--address", self.server_address, "stress"], check=True)
 
+    def test_unihash_exsits(self):
+        taskhash, outhash, unihash = self.create_test_hash(self.client)
+
+        p = self.run_hashclient([
+            "--address", self.server_address,
+            "unihash-exists", unihash,
+        ], check=True)
+        self.assertEqual(p.stdout.strip(), "true")
+
+        p = self.run_hashclient([
+            "--address", self.server_address,
+            "unihash-exists", '6662e699d6e3d894b24408ff9a4031ef9b038ee8',
+        ], check=True)
+        self.assertEqual(p.stdout.strip(), "false")
+
+    def test_unihash_exsits_quiet(self):
+        taskhash, outhash, unihash = self.create_test_hash(self.client)
+
+        p = self.run_hashclient([
+            "--address", self.server_address,
+            "unihash-exists", unihash,
+            "--quiet",
+        ])
+        self.assertEqual(p.returncode, 0)
+        self.assertEqual(p.stdout.strip(), "")
+
+        p = self.run_hashclient([
+            "--address", self.server_address,
+            "unihash-exists", '6662e699d6e3d894b24408ff9a4031ef9b038ee8',
+            "--quiet",
+        ])
+        self.assertEqual(p.returncode, 1)
+        self.assertEqual(p.stdout.strip(), "")
+
     def test_remove_taskhash(self):
         taskhash, outhash, unihash = self.create_test_hash(self.client)
         self.run_hashclient([