Add MySQL database hook "add_drop_database" configuration option to control whether dumped MySQL databases get dropped right before restore (#642).

NEWS

@@ -1,4 +1,6 @@
 1.7.7
+ * #642: Add MySQL database hook "add_drop_database" configuration option to control whether dumped
+   MySQL databases get dropped right before restore.
  * #643: Fix for potential data loss (data not getting backed up) when dumping large "directory"
    format PostgreSQL/MongoDB databases. Prior to the fix, these dumps would not finish writing to
    disk before Borg consumed them. Now, the dumping process completes before Borg starts. This only

borgmatic/config/schema.yaml

@@ -892,6 +892,13 @@ properties:
                                 file of that format, allowing more convenient
                                 restores of individual databases.
                             example: directory
+                        add_drop_database:
+                            type: boolean
+                            description: |
+                                Use the "--add-drop-database" flag with
+                                mysqldump, causing the database to be dropped
+                                right before restore. Defaults to true.
+                            example: false
                         options:
                             type: string
                             description: |

borgmatic/hooks/mysql.py

@@ -81,7 +81,7 @@ def execute_dump_command(
     dump_command = (
         ('mysqldump',)
         + (tuple(database['options'].split(' ')) if 'options' in database else ())
-        + ('--add-drop-database',)
+        + (('--add-drop-database',) if database.get('add_drop_database', True) else ())
         + (('--host', database['hostname']) if 'hostname' in database else ())
         + (('--port', str(database['port'])) if 'port' in database else ())
         + (('--protocol', 'tcp') if 'hostname' in database or 'port' in database else ())

tests/unit/hooks/test_mysql.py

@@ -159,6 +159,33 @@ def test_execute_dump_command_runs_mysqldump():
     )
 
 
+def test_execute_dump_command_runs_mysqldump_without_add_drop_database():
+    process = flexmock()
+    flexmock(module.dump).should_receive('make_database_dump_filename').and_return('dump')
+    flexmock(module.os.path).should_receive('exists').and_return(False)
+    flexmock(module.dump).should_receive('create_named_pipe_for_dump')
+
+    flexmock(module).should_receive('execute_command').with_args(
+        ('mysqldump', '--databases', 'foo', '>', 'dump',),
+        shell=True,
+        extra_environment=None,
+        run_to_completion=False,
+    ).and_return(process).once()
+
+    assert (
+        module.execute_dump_command(
+            database={'name': 'foo', 'add_drop_database': False},
+            log_prefix='log',
+            dump_path=flexmock(),
+            database_names=('foo',),
+            extra_environment=None,
+            dry_run=False,
+            dry_run_label='',
+        )
+        == process
+    )
+
+
 def test_execute_dump_command_runs_mysqldump_with_hostname_and_port():
     process = flexmock()
     flexmock(module.dump).should_receive('make_database_dump_filename').and_return('dump')