allow empty user for kerberos ticket usage

fix syntax problems:
* it is possible that sql injection is done, therefore the [DBNAME] syntax is used.
* it is not possible to use default escape on cursor.execute for DBNAME, since it will insert single quotes around the name and this will cause syntax problems / single quotes within the actual DBNAME

implement autocommit setting, since some content can not be imported within transaction

fix for automatic tests

fix problems with named instances, corrected error message regarding configuration file

remove unused placeholder

lib/ansible/modules/extras/database/mssql/mssql_db.py

@@ -26,7 +26,7 @@ module: mssql_db
 short_description: Add or remove MSSQL databases from a remote host.
 description:
    - Add or remove MSSQL databases from a remote host.
-version_added: "2.1"
+version_added: "2.2"
 options:
   name:
     description:
@@ -64,6 +64,12 @@ options:
       - Location, on the remote host, of the dump file to read from or write to. Uncompressed SQL
         files (C(.sql)) files are supported.
     required: false
+  autocommit:
+    description:
+      - Automatically commit the change only if the import succeed. Sometimes it is necessary to use autocommit=true, since some content can't be changed within a transaction.
+    required: false
+    default: false
+    choices: [ "false", "true" ]
 notes:
    - Requires the pymssql Python package on the remote host. For Ubuntu, this
      is as easy as pip install pymssql (See M(pip).)
@@ -79,6 +85,10 @@ EXAMPLES = '''
 - mssql_db: name=my_db state=import target=/tmp/dump.sql
 '''
 
+RETURN  = '''
+#
+'''
+
 import os
 try:
     import pymssql
@@ -89,44 +99,41 @@ else:
 
 
 def db_exists(conn, cursor, db):
-    cursor.execute("SELECT name FROM master.sys.databases WHERE name = N'%s'", db)
+    cursor.execute("SELECT name FROM master.sys.databases WHERE name = %s", db)
     conn.commit()
     return bool(cursor.rowcount)
 
 
 def db_create(conn, cursor, db):
-    conn.autocommit(True)
-    cursor.execute("CREATE DATABASE %s", db)
-    conn.autocommit(False)
+    cursor.execute("CREATE DATABASE [%s]" % db)
     return db_exists(conn, cursor, db)
 
 
 def db_delete(conn, cursor, db):
-    conn.autocommit(True)
     try:
-        single_user = "alter database %s set single_user with rollback immediate" % db
-        cursor.execute(single_user)
+        cursor.execute("ALTER DATABASE [%s] SET single_user WITH ROLLBACK IMMEDIATE" % db)
     except:
         pass
-    cursor.execute("DROP DATABASE %s", db)
-    conn.autocommit(False)
+    cursor.execute("DROP DATABASE [%s]" % db)
     return not db_exists(conn, cursor, db)
 
-
 def db_import(conn, cursor, module, db, target):
     if os.path.isfile(target):
-        with open(target, 'r') as backup:
-            sqlQuery = "USE %s\n"
+        backup = open(target, 'r')
+        try:
+            sqlQuery = "USE [%s]\n" % db
             for line in backup:
                 if line is None:
                     break
                 elif line.startswith('GO'):
-                    cursor.execute(sqlQuery, db)
-                    sqlQuery = "USE %s\n"
+                    cursor.execute(sqlQuery)
+                    sqlQuery = "USE [%s]\n" % db
                 else:
                     sqlQuery += line
-            cursor.execute(sqlQuery, db)
+            cursor.execute(sqlQuery)
             conn.commit()
+        finally:
+            backup.close()
         return 0, "import successful", ""
     else:
         return 1, "cannot find target file", "cannot find target file"
@@ -136,11 +143,12 @@ def main():
     module = AnsibleModule(
         argument_spec=dict(
             name=dict(required=True, aliases=['db']),
-            login_user=dict(required=True),
-            login_password=dict(required=True),
+            login_user=dict(default=''),
+            login_password=dict(default=''),
             login_host=dict(required=True),
-            login_port=dict(default="1433"),
+            login_port=dict(default='1433'),
             target=dict(default=None),
+            autocommit=dict(type='bool', default=False),
             state=dict(
                 default='present', choices=['present', 'absent', 'import'])
         )
@@ -151,16 +159,20 @@ def main():
 
     db = module.params['name']
     state = module.params['state']
+    autocommit = module.params['autocommit']
     target = module.params["target"]
 
     login_user = module.params['login_user']
     login_password = module.params['login_password']
     login_host = module.params['login_host']
     login_port = module.params['login_port']
+    
+    login_querystring = login_host
+    if login_port != "1433":
         login_querystring = "%s:%s" % (login_host, login_port)
 
-    if login_password is None or login_user is None:
-        module.fail_json(msg="when supplying login arguments, both login_user and login_password must be provided")
+    if login_user != "" and login_password == "":
+        module.fail_json(msg="when supplying login_user arguments login_password must be provided")
 
     try:
         conn = pymssql.connect(user=login_user, password=login_password, host=login_querystring, database='master')
@@ -170,9 +182,11 @@ def main():
                 errno, errstr = e.args
                 module.fail_json(msg="ERROR: %s %s" % (errno, errstr))
         else:
-                module.fail_json(msg="unable to connect, check login_user and login_password are correct, or alternatively check ~/.my.cnf contains credentials")
+                module.fail_json(msg="unable to connect, check login_user and login_password are correct, or alternatively check your @sysconfdir@/freetds.conf / ${HOME}/.freetds.conf")
 
+    conn.autocommit(True)
     changed = False
+
     if db_exists(conn, cursor, db):
         if state == "absent":
             try:
@@ -180,7 +194,9 @@ def main():
             except Exception, e:
                 module.fail_json(msg="error deleting database: " + str(e))
         elif state == "import":
+            conn.autocommit(autocommit)
             rc, stdout, stderr = db_import(conn, cursor, module, db, target)
+
             if rc != 0:
                 module.fail_json(msg="%s" % stderr)
             else:
@@ -196,7 +212,10 @@ def main():
                 changed = db_create(conn, cursor, db)
             except Exception, e:
                 module.fail_json(msg="error creating database: " + str(e))
+
+            conn.autocommit(autocommit)
             rc, stdout, stderr = db_import(conn, cursor, module, db, target)
+
             if rc != 0:
                 module.fail_json(msg="%s" % stderr)
             else: