def _perform_migration(search_app):
app_name = search_app.name
es_model = search_app.es_model
logger.info(f'Migrating the {app_name} search app')
read_alias_name = es_model.get_read_alias()
write_alias_name = es_model.get_write_alias()
new_index_name = es_model.get_target_index_name()
current_read_indices, current_write_index = es_model.get_read_and_write_indices(
)
if current_write_index not in current_read_indices:
raise DataHubException(
'Cannot migrate Elasticsearch index with a read alias referencing '
'a different index to the write alias', )
logger.info(f'Updating aliases for the {app_name} search app')
create_index(new_index_name, es_model._doc_type.mapping)
with start_alias_transaction() as alias_transaction:
alias_transaction.associate_indices_with_alias(read_alias_name,
[new_index_name])
alias_transaction.associate_indices_with_alias(write_alias_name,
[new_index_name])
alias_transaction.dissociate_indices_from_alias(
write_alias_name, [current_write_index])
_schedule_resync(search_app)
def test_update_alias(mock_es_client, add_actions, remove_actions,
expected_body):
"""Test get_aliases_for_index()."""
client = mock_es_client.return_value
with elasticsearch.start_alias_transaction() as alias_transaction:
for action in add_actions:
alias_transaction.associate_indices_with_alias(
action[0], action[1])
for action in remove_actions:
alias_transaction.dissociate_indices_from_alias(
action[0], action[1])
client.indices.update_aliases.assert_called_with(body=expected_body)
def _clean_up_aliases_and_indices(search_app):
es_model = search_app.es_model
read_alias = es_model.get_read_alias()
read_indices, write_index = es_model.get_read_and_write_indices()
if write_index not in read_indices:
raise DataHubException(
'Write index not in read alias, aborting mapping migration...')
indices_to_remove = read_indices - {write_index}
if indices_to_remove:
with start_alias_transaction() as alias_transaction:
alias_transaction.dissociate_indices_from_alias(
read_alias, indices_to_remove)
else:
logger.warning(f'No indices to remove for the {read_alias} alias')
for index in indices_to_remove:
if not get_aliases_for_index(index):
delete_index(index)