Fix the "create" action with the "--dry-run" flag querying for databases when a PostgreSQL/MySQL "all" database is configured.

NEWS

@@ -4,6 +4,8 @@
    This lines up with the new behavior in Borg 2.0.0b5.
  * Internally support new Borg 2.0.0b5 "--filter" status characters / item flags for the "create"
    action.
+ * Fix the "create" action with the "--dry-run" flag querying for databases when a PostgreSQL/MySQL
+   "all" database is configured. Now, these queries are skipped due to the dry run.
 
 1.7.7
  * #642: Add MySQL database hook "add_drop_database" configuration option to control whether dumped

borgmatic/hooks/mysql.py

@@ -24,7 +24,7 @@ def make_dump_path(location_config):  # pragma: no cover
 SYSTEM_DATABASE_NAMES = ('information_schema', 'mysql', 'performance_schema', 'sys')
 
 
-def database_names_to_dump(database, extra_environment, log_prefix, dry_run_label):
+def database_names_to_dump(database, extra_environment, log_prefix, dry_run):
     '''
     Given a requested database config, return the corresponding sequence of database names to dump.
     In the case of "all", query for the names of databases on the configured host and return them,
@@ -32,6 +32,8 @@ def database_names_to_dump(database, extra_environment, log_prefix, dry_run_labe
     '''
     if database['name'] != 'all':
         return (database['name'],)
+    if dry_run:
+        return ()
 
     show_command = (
         ('mysql',)
@@ -43,9 +45,7 @@ def database_names_to_dump(database, extra_environment, log_prefix, dry_run_labe
         + ('--skip-column-names', '--batch')
         + ('--execute', 'show schemas')
     )
-    logger.debug(
-        '{}: Querying for "all" MySQL databases to dump{}'.format(log_prefix, dry_run_label)
-    )
+    logger.debug(f'{log_prefix}: Querying for "all" MySQL databases to dump')
     show_output = execute_command_and_capture_output(
         show_command, extra_environment=extra_environment
     )
@@ -125,9 +125,13 @@ def dump_databases(databases, log_prefix, location_config, dry_run):
         dump_path = make_dump_path(location_config)
         extra_environment = {'MYSQL_PWD': database['password']} if 'password' in database else None
         dump_database_names = database_names_to_dump(
-            database, extra_environment, log_prefix, dry_run_label
+            database, extra_environment, log_prefix, dry_run
         )
+
         if not dump_database_names:
+            if dry_run:
+                continue
+
             raise ValueError('Cannot find any MySQL databases to dump.')
 
         if database['name'] == 'all' and database.get('format'):

borgmatic/hooks/postgresql.py

@@ -43,7 +43,7 @@ def make_extra_environment(database):
 EXCLUDED_DATABASE_NAMES = ('template0', 'template1')
 
 
-def database_names_to_dump(database, extra_environment, log_prefix, dry_run_label):
+def database_names_to_dump(database, extra_environment, log_prefix, dry_run):
     '''
     Given a requested database config, return the corresponding sequence of database names to dump.
     In the case of "all" when a database format is given, query for the names of databases on the
@@ -56,6 +56,8 @@ def database_names_to_dump(database, extra_environment, log_prefix, dry_run_labe
         return (requested_name,)
     if not database.get('format'):
         return ('all',)
+    if dry_run:
+        return ()
 
     list_command = (
         ('psql', '--list', '--no-password', '--csv', '--tuples-only')
@@ -64,9 +66,7 @@ def database_names_to_dump(database, extra_environment, log_prefix, dry_run_labe
         + (('--username', database['username']) if 'username' in database else ())
         + (tuple(database['list_options'].split(' ')) if 'list_options' in database else ())
     )
-    logger.debug(
-        '{}: Querying for "all" PostgreSQL databases to dump{}'.format(log_prefix, dry_run_label)
-    )
+    logger.debug(f'{log_prefix}: Querying for "all" PostgreSQL databases to dump')
     list_output = execute_command_and_capture_output(
         list_command, extra_environment=extra_environment
     )
@@ -99,10 +99,13 @@ def dump_databases(databases, log_prefix, location_config, dry_run):
         extra_environment = make_extra_environment(database)
         dump_path = make_dump_path(location_config)
         dump_database_names = database_names_to_dump(
-            database, extra_environment, log_prefix, dry_run_label
+            database, extra_environment, log_prefix, dry_run
         )
 
         if not dump_database_names:
+            if dry_run:
+                continue
+
             raise ValueError('Cannot find any PostgreSQL databases to dump.')
 
         for database_name in dump_database_names:

tests/unit/hooks/test_mysql.py

@@ -9,26 +9,36 @@ from borgmatic.hooks import mysql as module
 def test_database_names_to_dump_passes_through_name():
     extra_environment = flexmock()
     log_prefix = ''
-    dry_run_label = ''
 
     names = module.database_names_to_dump(
-        {'name': 'foo'}, extra_environment, log_prefix, dry_run_label
+        {'name': 'foo'}, extra_environment, log_prefix, dry_run=False
     )
 
     assert names == ('foo',)
 
 
+def test_database_names_to_dump_bails_for_dry_run():
+    extra_environment = flexmock()
+    log_prefix = ''
+    flexmock(module).should_receive('execute_command_and_capture_output').never()
+
+    names = module.database_names_to_dump(
+        {'name': 'all'}, extra_environment, log_prefix, dry_run=True
+    )
+
+    assert names == ()
+
+
 def test_database_names_to_dump_queries_mysql_for_database_names():
     extra_environment = flexmock()
     log_prefix = ''
-    dry_run_label = ''
     flexmock(module).should_receive('execute_command_and_capture_output').with_args(
         ('mysql', '--skip-column-names', '--batch', '--execute', 'show schemas'),
         extra_environment=extra_environment,
     ).and_return('foo\nbar\nmysql\n').once()
 
     names = module.database_names_to_dump(
-        {'name': 'all'}, extra_environment, log_prefix, dry_run_label
+        {'name': 'all'}, extra_environment, log_prefix, dry_run=False
     )
 
     assert names == ('foo', 'bar')
@@ -323,7 +333,6 @@ def test_execute_dump_command_with_dry_run_skips_mysqldump():
 
 def test_dump_databases_errors_for_missing_all_databases():
     databases = [{'name': 'all'}]
-    process = flexmock()
     flexmock(module).should_receive('make_dump_path').and_return('')
     flexmock(module.dump).should_receive('make_database_dump_filename').and_return(
         'databases/localhost/all'
@@ -331,7 +340,18 @@ def test_dump_databases_errors_for_missing_all_databases():
     flexmock(module).should_receive('database_names_to_dump').and_return(())
 
     with pytest.raises(ValueError):
-        assert module.dump_databases(databases, 'test.yaml', {}, dry_run=False) == [process]
+        assert module.dump_databases(databases, 'test.yaml', {}, dry_run=False)
+
+
+def test_dump_databases_does_not_error_for_missing_all_databases_with_dry_run():
+    databases = [{'name': 'all'}]
+    flexmock(module).should_receive('make_dump_path').and_return('')
+    flexmock(module.dump).should_receive('make_database_dump_filename').and_return(
+        'databases/localhost/all'
+    )
+    flexmock(module).should_receive('database_names_to_dump').and_return(())
+
+    assert module.dump_databases(databases, 'test.yaml', {}, dry_run=True) == []
 
 
 def test_restore_database_dump_runs_mysql_to_restore():

tests/unit/hooks/test_postgresql.py

@@ -9,19 +9,32 @@ from borgmatic.hooks import postgresql as module
 def test_database_names_to_dump_passes_through_individual_database_name():
     database = {'name': 'foo'}
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == ('foo',)
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
+        'foo',
+    )
 
 
 def test_database_names_to_dump_passes_through_individual_database_name_with_format():
     database = {'name': 'foo', 'format': 'custom'}
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == ('foo',)
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
+        'foo',
+    )
 
 
 def test_database_names_to_dump_passes_through_all_without_format():
     database = {'name': 'all'}
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == ('all',)
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
+        'all',
+    )
+
+
+def test_database_names_to_dump_with_all_and_format_and_dry_run_bails():
+    database = {'name': 'all', 'format': 'custom'}
+    flexmock(module).should_receive('execute_command_and_capture_output').never()
+
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=True) == ()
 
 
 def test_database_names_to_dump_with_all_and_format_lists_databases():
@@ -30,7 +43,7 @@ def test_database_names_to_dump_with_all_and_format_lists_databases():
         'foo,test,\nbar,test,"stuff and such"'
     )
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == (
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
         'foo',
         'bar',
     )
@@ -53,7 +66,7 @@ def test_database_names_to_dump_with_all_and_format_lists_databases_with_hostnam
         extra_environment=object,
     ).and_return('foo,test,\nbar,test,"stuff and such"')
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == (
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
         'foo',
         'bar',
     )
@@ -66,7 +79,7 @@ def test_database_names_to_dump_with_all_and_format_lists_databases_with_usernam
         extra_environment=object,
     ).and_return('foo,test,\nbar,test,"stuff and such"')
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == (
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
         'foo',
         'bar',
     )
@@ -79,7 +92,7 @@ def test_database_names_to_dump_with_all_and_format_lists_databases_with_options
         extra_environment=object,
     ).and_return('foo,test,\nbar,test,"stuff and such"')
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == (
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
         'foo',
         'bar',
     )
@@ -91,7 +104,9 @@ def test_database_names_to_dump_with_all_and_format_excludes_particular_database
         'foo,test,\ntemplate0,test,blah'
     )
 
-    assert module.database_names_to_dump(database, flexmock(), flexmock(), flexmock()) == ('foo',)
+    assert module.database_names_to_dump(database, flexmock(), flexmock(), dry_run=False) == (
+        'foo',
+    )
 
 
 def test_dump_databases_runs_pg_dump_for_each_database():
@@ -139,6 +154,15 @@ def test_dump_databases_raises_when_no_database_names_to_dump():
         module.dump_databases(databases, 'test.yaml', {}, dry_run=False)
 
 
+def test_dump_databases_does_not_raise_when_no_database_names_to_dump():
+    databases = [{'name': 'foo'}, {'name': 'bar'}]
+    flexmock(module).should_receive('make_extra_environment').and_return({'PGSSLMODE': 'disable'})
+    flexmock(module).should_receive('make_dump_path').and_return('')
+    flexmock(module).should_receive('database_names_to_dump').and_return(())
+
+    module.dump_databases(databases, 'test.yaml', {}, dry_run=True) == []
+
+
 def test_dump_databases_with_duplicate_dump_skips_pg_dump():
     databases = [{'name': 'foo'}, {'name': 'bar'}]
     flexmock(module).should_receive('make_extra_environment').and_return({'PGSSLMODE': 'disable'})