Maceo - Analyze and anonymize data in real-time

Maceo is an OpenFaaS serverless function designed to analyze and anonymize personally identifiable information (PII) in real-time. It leverages the powerful capabilities of Microsoft Presidio to detect and redact sensitive data such as names, phone numbers, emails, and more.

Features

• 🧠 PII Detection – Uses Presidio Analyzer to identify PII in text
• 🛡️ Anonymization – Applies Presidio Anonymizer to redact detected PII
• ⚡ Real-Time Functionality – Runs as an OpenFaaS function for scalable, on-demand usage
• 🔧 Configurable – Customize what types of PII to detect

Use Cases

• Data privacy compliance (e.g., GDPR, HIPAA)
• Real-time chat or support log redaction
• Secure logging or auditing pipelines
• Anonymizing customer feedback or user-generated content

Architecture

Maceo serves as a wrapper function that accepts a plain text, sends the input to Presidio for analysis and anonymization and returns the redacted version of the original text.

Getting Started

Prerequisites

• OpenFaaS installed and running
• Microsoft Presidio - For PII anonymization in text installed and running

Deploying with OpenFaaS

export OPENFAAS_URL=https://openfaas.example.com
faas-cli secret create --from-literal='{}' maceo
faas-cli deploy --image=ghcr.io/tschaefer/maceo:0.1.0 --name=maceo

This creates the required empty configuration secret for the function and deploys the function to your OpenFaaS instance.

See Blog Post for a detailed guide on how to set up with faasd.

Usage

Send a POST request to the function with a plain text payload.

curl --include --request POST https://maceo.example.com \
  --header "Content-Type: text/plain; charset=utf-8" \
  --data-binary  "@contrib/sample"
HTTP/2 200
content-type: text/plain; charset=utf-8
date: Tue, 13 May 2025 05:47:25 GMT
x-call-id: fa2bf983-869a-4bca-b68b-cfb7a3140d0c
x-duration-seconds: 0.078652
x-maceo-commit: ca7eea42494e47927860f2493ef05f54fbfd3a1f
x-maceo-version: 0.1.0
x-openfaas-eula: openfaas-ce
x-served-by: openfaas-ce/0.27.12
x-start-time: 1747115245869918778
content-length: 1157

Sample Job Application Letter
Ms. <PERSON>
DSC Company
68 <LOCATION>, CA 09045
<PHONE_NUMBER>

May 11, 2025

Dear Ms. <PERSON>,

I am writing this letter to apply for a junior programmer position advertised in your organisation. As requested, I am enclosing a completed job application, my certificates, my resumes, and four references in this letter.

The opportunity presented in this listing is exciting. I believe that my firm and years of technical experiences and education will make me a competent person for the position. The main strengths that I have, which I will contribute to this position include:

I have designed, developed and supported many different live use applications.
I continuously work towards achieving my goals through hard work and excellence.
I provide exceptional contributions to the needs and wants of the consumers.
I have a Bachelor of Science degree in Computer Programming. Additionally, I have in-depth knowledge of the complete cycle of a soft development project. Whenever the need arises, I learn new technologies.
I can be reached on <PHONE_NUMBER>.
Thank you for your time and consideration.

Sincerely,

<PERSON>

Configuration

The function can be configured using a secret. The secret is a JSON object containing the following keys:

• upstreams: The URLs of the Presidio Analyzer and Anonymizer services.
  • analyze: The URL for the Presidio Analyzer service. (default: http://10.62.0.1:5001)
  • anonymize: The URL for the Presidio Anonymizer service. (default: http://10.62.0.1:5002)
• entities: The list of PII entities to detect and anonymize. (default: nil)
• language: The language to use for PII detection. (default: en)
• score_threshold: The minimum score for a PII entity to be considered detected. (default: 0.0)
• anonymizers: The anonymizer to use for value replacement. (default: nil)
• ad_hoc_recognizers: The list of ad-hoc recognizers to use for PII detection. (default: nil)

Find an example configuration in the contrib/config file.

Health Check

The function exposes a health check endpoint at /health. The check verifies the syntax of the configuration secret and the availability of the Presidio services. It returns a 200 OK status if everything is working correctly and a 500 status if there are any issues.

curl --include --request GET https://maceo.example.com/health
HTTP/2 200
content-type: text/plain
date: Tue, 13 May 2025 06:43:24 GMT
x-call-id: 0985e928-fc7d-454a-aab2-620c4c32e533
x-duration-seconds: 0.007149
x-maceo-commit: ca7eea42494e47927860f2493ef05f54fbfd3a1f
x-maceo-version: 0.1.0
x-openfaas-eula: openfaas-ce
x-served-by: openfaas-ce/0.27.12
x-start-time: 1747118604460379210
content-length: 0

Contributing

Contributions are welcome! Please fork the repository and submit a pull request. For major changes, open an issue first to discuss what you would like to change.

Ensure that your code adheres to the existing style and includes appropriate tests.

License

This project is licensed under the MIT License.