Fix big job binary objects in mysql

Fixes bug: #1302579

Change-Id: I3acc13864c41127c341875e350b4611ff7035e29

doc/source/userdoc/installation.guide.rst

@@ -115,14 +115,28 @@ To install into a virtual environment
 
     check each option in sahara-venv/etc/sahara.conf, and make necessary changes
 
-5. Create database schema:
+5. If you use Sahara with MySQL database, then for storing big Job Binaries
+   in Sahara Internal Database you must configure size of max allowed packet.
+   Edit ``my.cnf`` and change parameter:
+
+.. sourcecode:: ini
+
+   ...
+   [mysqld]
+   ...
+   max_allowed_packet          = 256M
+..
+
+    and restart mysql server.
+
+6. Create database schema:
 
 .. sourcecode:: console
 
     $ sahara-venv/bin/python sahara-venv/bin/sahara-db-manage --config-file sahara-venv/etc/sahara.conf upgrade head
 ..
 
-6. To start Sahara call:
+7. To start Sahara call:
 
 .. sourcecode:: console
 

sahara/db/base.py

@@ -33,3 +33,7 @@ class Base(object):
 
     def __init__(self):
         self.db = importutils.import_module(CONF.db_driver)
+
+
+def is_mysql_avail():
+    return CONF.database.connection.startswith('mysql')

sahara/db/migration/alembic_migrations/versions/001_icehouse.py

@@ -111,7 +111,7 @@ def upgrade():
                     sa.Column('tenant_id', sa.String(length=36),
                               nullable=True),
                     sa.Column('name', sa.String(length=80), nullable=False),
-                    sa.Column('data', sa.LargeBinary(), nullable=True),
+                    sa.Column('data', st.LargeBinary(), nullable=True),
                     sa.Column('datasize', sa.BIGINT(), nullable=True),
                     sa.PrimaryKeyConstraint('id'),
                     sa.UniqueConstraint('name', 'tenant_id'),

sahara/db/sqlalchemy/models.py

@@ -331,8 +331,7 @@ class JobBinaryInternal(mb.SaharaBase):
     id = _id_column()
     tenant_id = sa.Column(sa.String(36))
     name = sa.Column(sa.String(80), nullable=False)
-
-    data = sa.orm.deferred(sa.Column(sa.LargeBinary))
+    data = sa.orm.deferred(sa.Column(st.LargeBinary()))
     datasize = sa.Column(sa.BIGINT)
 
 

sahara/db/sqlalchemy/types.py

@@ -14,8 +14,10 @@
 # limitations under the License.
 
 import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
 from sqlalchemy.ext import mutable
 
+from sahara.db import base
 from sahara.openstack.common import jsonutils
 
 
@@ -108,3 +110,9 @@ def JsonDictType():
 def JsonListType():
     """Returns an SQLAlchemy Column Type suitable to store a Json array."""
     return MutableList.as_mutable(JsonEncoded)
+
+
+def LargeBinary():
+    if base.is_mysql_avail():
+        return mysql.LONGBLOB
+    return sa.LargeBinary

sahara/tests/unit/db/migration/test_migrations.py

@@ -37,6 +37,8 @@ postgres=# create database openstack_citest with owner openstack_citest;
 
 """
 
+import os
+
 from oslo.config import cfg
 
 from sahara.openstack.common.db.sqlalchemy import utils as db_utils
@@ -323,6 +325,17 @@ class TestMigrations(base.BaseWalkMigrationTestCase, base.CommonTestsMixIn):
         self.assertColumnsExists(engine, 'instances', instances_columns)
         self.assertColumnCount(engine, 'instances', instances_columns)
 
+        self._data_001(engine, data)
+
+    def _data_001(self, engine, data):
+        datasize = 512 * 1024  # 512kB
+        data = os.urandom(datasize)
+        t = db_utils.get_table(engine, 'job_binary_internal')
+        engine.execute(t.insert(), data=data, id='123', name='name')
+        new_data = engine.execute(t.select()).fetchone().data
+        self.assertEqual(data, new_data)
+        engine.execute(t.delete())
+
     def _check_002(self, engine, data):
         # currently, 002 is just a placeholder
         self._check_001(engine, data)