| <!-- |
| ~ Licensed to the Apache Software Foundation (ASF) under one |
| ~ or more contributor license agreements. See the NOTICE file |
| ~ distributed with this work for additional information |
| ~ regarding copyright ownership. The ASF licenses this file |
| ~ to you under the Apache License, Version 2.0 (the |
| ~ "License"); you may not use this file except in compliance |
| ~ with the License. You may obtain a copy of the License at |
| ~ |
| ~ http://www.apache.org/licenses/LICENSE-2.0 |
| ~ |
| ~ Unless required by applicable law or agreed to in writing, |
| ~ software distributed under the License is distributed on an |
| ~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| ~ KIND, either express or implied. See the License for the |
| ~ specific language governing permissions and limitations |
| ~ under the License. |
| --> |
| |
| #### Problem |
| The idea of this test group is to simulate issues that can arise during rolling upgrade/downgrade. |
| |
| #### Implementation |
| In this test group, the docker compose cluster is launched with services on different versions. |
| The docker image for the previous version is built by downloading the previous version druid tar. |
| Currently, the case where Coordinator and Overlord is on the previous version is tested. |
| |
| #### Test coverage |
| Existing |
| - MSQ ingestion |
| - Native ingestion |
| - Stream ingestion |
| - Querying |
| |
| Pending |
| - Compaction |
| |
| #### Limitations |
| * `druid-testing-tools` jar is not published. The image for the previous version still uses the |
| extension from the current build. |
| This could break in case of incompatible changes in this extension. |
| In such a scenario the test should be disabled. However, this extension is primarily used to |
| test specific error scenarios and launch custom node role service (used in HighAvailability test group). |
