bitbake: hashserv: Add db-usage API

Adds an API to query the server for the usage of the database (e.g. how
many rows are present in each table)

(Bitbake rev: c9c1224447e147e0de92953bc85cea75670b898c)

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

bitbake/lib/hashserv/sqlalchemy.py

@@ -27,6 +27,7 @@ from sqlalchemy import (
     and_,
     delete,
     update,
+    func,
 )
 import sqlalchemy.engine
 from sqlalchemy.orm import declarative_base
@@ -401,3 +402,16 @@ class Database(object):
         async with self.db.begin():
             result = await self.db.execute(statement)
             return result.rowcount != 0
+
+    async def get_usage(self):
+        usage = {}
+        async with self.db.begin() as session:
+            for name, table in Base.metadata.tables.items():
+                statement = select(func.count()).select_from(table)
+                self.logger.debug("%s", statement)
+                result = await self.db.execute(statement)
+                usage[name] = {
+                    "rows": result.scalar(),
+                }
+
+        return usage