enable support for backup and restore operations in SQL Server (ticket 19687)

2 files changed, 74 insertions, 0 deletions

diff --git a/adbh.py b/adbh.py
index 9537ad8..1dbb979 100644
--- a/adbh.py
+++ b/adbh.py
@@ -16,6 +16,8 @@ Helpers are provided for postgresql, mysql and sqlite.
 """
 __docformat__ = "restructuredtext en"
 
+import os
+import sys
 
 class BadQuery(Exception): pass
 class UnsupportedFunction(BadQuery): pass
@@ -175,6 +177,7 @@ class _GenericAdvFuncHelper:
         """return a list of commands to restore a backup of the given database"""
         raise NotImplementedError('not supported by this DBMS')
 
+
     # helpers to standardize SQL according to the database
 
     def sql_current_date(self):
@@ -595,6 +598,59 @@ class _SqlServer2005FuncHelper(_GenericAdvFuncHelper):
         return StringIO.StringIO(value)
 
 
+    def backup_command(self, dbname, dbhost, dbuser, backupfile,
+                       keepownership=True):
+        """return a command to backup the given database"""
+        return [sys.executable, os.path.normpath(__file__), 
+                "_SqlServer2005FuncHelper._do_backup", dbhost, dbname, backupfile]
+
+    def restore_commands(self, dbname, dbhost, dbuser, backupfile,
+                         encoding='utf-8', keepownership=True, drop=True):
+        """return a list of commands to restore a backup of the given database"""
+        return [[sys.executable, os.path.normpath(__file__), 
+                "_SqlServer2005FuncHelper._do_restore", dbhost, dbname, backupfile],
+                ]
+    
+    @staticmethod
+    def _do_backup():
+        import time
+        from logilab.common.db import get_connection
+        dbhost = sys.argv[2]
+        dbname = sys.argv[3]
+        filename = sys.argv[4]
+        cnx = get_connection(driver='sqlserver2005', host=dbhost, database=dbname, extra_args='autocommit;trusted_connection')
+        cursor = cnx.cursor()
+        cursor.execute("BACKUP DATABASE ? TO DISK= ? ", (dbname, filename,))
+        prev_size = -1
+        err_count = 0
+        same_size_count = 0
+        while err_count < 10 and same_size_count < 10:
+            time.sleep(1)
+            try:
+                size = os.path.getsize(filename)
+            except OSError, exc:
+                err_count +=1
+                print exc
+            if size > prev_size:
+                same_size_count = 0
+                prev_size = size
+            else:
+               same_size_count += 1
+        cnx.close()
+        sys.exit(0)
+        
+    @staticmethod
+    def _do_restore():
+        """return the SQL statement to restore a backup of the given database"""
+        from logilab.common.db import get_connection
+        dbhost = sys.argv[2]
+        dbname = sys.argv[3]
+        filename = sys.argv[4]
+        cnx = get_connection(driver='sqlserver2005', host=dbhost, database='master', extra_args='autocommit;trusted_connection')
+        cursor = cnx.cursor()
+        cursor.execute("RESTORE DATABASE ? FROM DISK= ? WITH REPLACE", (dbname, filename,))
+        sys.exit(0)
+
 ADV_FUNC_HELPER_DIRECTORY = {'postgres': _PGAdvFuncHelper(),
                              'sqlite': _SqliteAdvFuncHelper(),
                              'mysql': _MyAdvFuncHelper(),
@@ -616,3 +672,7 @@ def auto_register_function(funcdef):
     """register the function `funcdef` on supported backends"""
     for driver in  funcdef.supported_backends:
         register_function(driver, funcdef)
+
+if __name__ == "__main__": # used to backup sql server db
+    func_call = sys.argv[1]
+    eval(func_call+'()')
diff --git a/db.py b/db.py
index 45ff04c..c51190d 100644
--- a/db.py
+++ b/db.py
@@ -604,6 +604,7 @@ class _MySqlDBAdapter(DBAPIAdapter):
 class _BaseSqlServerAdapter(DBAPIAdapter):
     driver = 'Override in subclass'
     _use_trusted_connection = False
+    _use_autocommit = False
     _fetch_lock = threading.Lock()
 
     @classmethod
@@ -613,11 +614,22 @@ class _BaseSqlServerAdapter(DBAPIAdapter):
         Authentication (i.e. passwordless auth)
         """
         klass._use_trusted_connection = use_trusted
+
+    @classmethod
+    def use_autocommit(klass, use_autocommit=False):
+        """
+        pass True to this class method to enable autocommit (required
+        for backup and restore)
+        """
+        klass._use_autocommit = use_autocommit
+
     @classmethod
     def _process_extra_args(klass, arguments):
         arguments = arguments.lower().split(';')
         if 'trusted_connection' in arguments:
             klass.use_trusted_connection(True)
+        if 'autocommit' in arguments:
+            klass.use_autocommit(True)
 
     def connect(self, host='', database='', user='', password='', port=None, extra_args=None):
         """Handles pyodbc connection format
@@ -750,6 +762,8 @@ class _PyodbcAdapter(_BaseSqlServerAdapter):
             variables['Trusted_Connection'] = 'yes'
             del variables['user']
             del variables['password']
+        if self._use_autocommit:
+            variables['autocommit'] = True
         return self._native_module.connect(**variables)
 
 class _PyodbcSqlServer2000Adapter(_PyodbcAdapter):