simonbence opened a new pull request #4839: URL: https://github.com/apache/nifi/pull/4839
_Note: this review is a successor of [PR 4821](https://github.com/apache/nifi/pull/4821). In order to keep the changes readable I decided to abandon that one and start a fresh pull request._ This would be a proposal for having persistent status history for both component and node level metrics. I decided to approach the question using `QuestDB` which is an embeddable time series database written in Java. During my tests, the performance and the memory footprint are looked reasonable. As for code organisation of the new implementation I worked with three concepts: repository is the top level entity, provides the service for the clients (`FlowController`, etc.). In general, this is the same as before, with minor changes (the name has been changed to `StatusHistoryRepostiory` to server the intent better, also start and stop hooks were added). The storage classes are part of the repositories and are responsible for manage the details of a given type, like processor status, node status, etc. Finally the `WriterTemplates` and `ReaderTemplates` are merely helpers exist to deal with `QuestDB` API calls. Some remarks on design decisions: - The PR contains a small fix on ProcessGroupStatusDescriptor#calculateTaskMillis(): previously every subsequent level makes a nano->milli conversion, which accumulates, reducing the task time in children groups into 0. Now this should be fixed (The QuestDB tests are implicitly proves this as well) - Configuration contains the new parameters but they are commented out. These are relevant for the QuestDB implementation and if not used the implementation will go with default values. At this point I think, the VolatileComponentStatusRepository should be kept as default implementation - The implementation depends on the latest of the 4.X version of QuestDB. Currently QuestDB is at 5.0.5, but the 5.X line depends on Java 11. There are some non vital features in 5.X (all_tables request, dropping partition using WHERE closure), but these are not unavoidable for us. - QuestDB can be called using `PostrgeSQL` driver via `JDBC` if it is not embedded. Also it provides supports `InfluxDB` protocol. These are possibilities were not utilised: QuestDB's own API seems to be sufficient and robust for our purposes. In order to streamline the review of the contribution we ask you to ensure the following steps have been taken: ### For all changes: - [ ] Is there a JIRA ticket associated with this PR? Is it referenced in the commit message? - [ ] Does your PR title start with **NIFI-XXXX** where XXXX is the JIRA number you are trying to resolve? Pay particular attention to the hyphen "-" character. - [ ] Has your PR been rebased against the latest commit within the target branch (typically `main`)? - [ ] Is your initial contribution a single, squashed commit? _Additional commits in response to PR reviewer feedback should be made on this branch and pushed to allow change tracking. Do not `squash` or use `--force` when pushing to allow for clean monitoring of changes._ ### For code changes: - [ ] Have you ensured that the full suite of tests is executed via `mvn -Pcontrib-check clean install` at the root `nifi` folder? - [ ] Have you written or updated unit tests to verify your changes? - [ ] Have you verified that the full build is successful on JDK 8? - [ ] Have you verified that the full build is successful on JDK 11? - [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0](http://www.apache.org/legal/resolved.html#category-a)? - [ ] If applicable, have you updated the `LICENSE` file, including the main `LICENSE` file under `nifi-assembly`? - [ ] If applicable, have you updated the `NOTICE` file, including the main `NOTICE` file found under `nifi-assembly`? - [ ] If adding new Properties, have you added `.displayName` in addition to .name (programmatic access) for each of the new properties? ### For documentation related changes: - [ ] Have you ensured that format looks appropriate for the output in which it is rendered? ### Note: Please ensure that once the PR is submitted, you check GitHub Actions CI for build issues and submit an update to your PR as soon as possible. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
