Scrooge-McDucks opened a new pull request, #11583:
URL: https://github.com/apache/nifi/pull/11583
Adds DetectBase64Content, a processor that determines whether FlowFile
content is Base64 encoded by inspecting its characters rather than attempting a
decode. The result is written as true or false to a configurable attribute, and
the FlowFile is always routed to success — downstream flows can branch with
RouteOnAttribute instead of relying on a decode failure as the signal.
Detection Scope selects between two modes:
Entire Content — reads the full FlowFile for a definitive result.
Sample Size — reads a configurable number of bytes for a bounded check on
large content.
Content is streamed in both modes, so heap usage stays constant regardless
of FlowFile size.
Detection rules
Content is reported as Base64 when all of the following hold:
It contains at least one character from the standard alphabet defined in RFC
4648 §4.
It contains no characters outside that alphabet, other than line separators
and terminating padding.
It has no more than two padding characters.
When the entire content is read, the character count is a multiple of four.
Alternatives considered
ValidatingBase64InputStream — considered, but doesn't fit this use case. It
delegates to Commons Codec's Base64.isBase64(), which only checks alphabet
membership and treats whitespace as valid — so plain text like hello world
passes. It also doesn't check padding placement, padding count, or content
length. Detection still needs to inspect every byte against those additional
rules, so the wrapper would only be useful for rejecting out-of-alphabet
characters — not for the rest of the validation.
<!-- 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. -->
# Summary
[NIFI-00000](https://issues.apache.org/jira/browse/NIFI-00000)
# Tracking
Please complete the following tracking steps prior to pull request creation.
### Issue Tracking
- [Apache NiFi Jira](https://issues.apache.org/jira/browse/NIFI) issue
created
### Pull Request Tracking
- Pull Request title starts with Apache NiFi Jira issue number, such as
`NIFI-00000`
- Pull Request commit message starts with Apache NiFi Jira issue number, as
such `NIFI-00000`
- 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
- Pull Request based on current revision of the `main` branch
- 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`
- [ X] JDK 21
- [ X] JDK 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
- [ X] Documentation formatting appears as expected in rendered files
--
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]
