Vinz2168 opened a new pull request, #11863: URL: https://github.com/apache/nifi/pull/11863
# Summary [NIFI-16524](https://issues.apache.org/jira/browse/NIFI-16524) This adds a new `nifi-mcp-bundle` that lets NiFi act as a client of [Model Context Protocol](https://modelcontextprotocol.io) (MCP) servers, so flows can consume MCP tools, resources and prompts deterministically, without an LLM in the loop. - `McpClientService` (API) and `StandardMcpClientService`: one MCP session per service, shared by all referencing processors, over Streamable HTTP or SSE, with an optional SSL Context Service (TLS/mTLS), Bearer Token and sensitive dynamic properties sent as HTTP headers. It connects lazily if the server is down when the service is enabled, reconnects after transport failures, and supports config verification. - `InvokeMcpServer`: Call Tool, Read Resource, Get Prompt and List Tools/Resources/Prompts. Arguments come from FlowFile content or from a property with Expression Language. Output can be the full result, text only, or the tool's `structuredContent`. Relationships: `success`, `tool error` (`isError: true`), `original` and `failure`. - Dependencies: the MCP Java SDK (MIT) plus Reactor, Jackson 3 (managed by the NiFi BOM), json-schema-validator, SnakeYAML Engine, ITU (Apache 2.0) and Reactive Streams (CC0). All are documented in the NAR's `LICENSE`/`NOTICE`. - The NAR is left out of the default assembly behind an optional `include-mcp` profile. - STDIO transport is intentionally out of scope for this PR because of its security implications. Unit tests run the processor against a fake service, and the service against a real in-process MCP Java SDK server on Jetty, so no network is needed. # Tracking Please complete the following tracking steps prior to pull request creation. ### Issue Tracking - [x] [Apache NiFi Jira](https://issues.apache.org/jira/browse/NIFI) issue created ### Pull Request Tracking - [x] Pull Request title starts with Apache NiFi Jira issue number, such as `NIFI-00000` - [x] Pull Request commit message starts with Apache NiFi Jira issue number, as such `NIFI-00000` - [x] Pull request contains [commits signed](https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits) with a registered key indicating `Verified` status ### Pull Request Formatting - [x] Pull Request based on current revision of the `main` branch - [x] Pull Request refers to a feature branch with one commit containing changes # Verification Please indicate the verification steps performed prior to pull request creation. ### Build - [x] Build completed using `./mvnw clean install -P contrib-check` (bundle modules) - [ ] JDK 21 - [ ] JDK 25 Built and tested locally on JDK 26; relying on CI for JDK 21 and 25. ### Licensing - [x] New dependencies are compatible with the [Apache License 2.0](https://apache.org/licenses/LICENSE-2.0) according to the [License Policy](https://www.apache.org/legal/resolved.html) - [x] New dependencies are documented in applicable `LICENSE` and `NOTICE` files ### Documentation - [ ] Documentation formatting appears as expected in rendered files 🤖 Generated with [Claude Code](https://claude.com/claude-code) -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
