The Problem

HAR files contain everything your browser sends and receives—passwords, API keys, tokens, emails, IP addresses. Support teams need them for debugging, but sharing them raw is a security nightmare. Manually editing is error-prone: miss one token in a 10MB file and you have a breach. Even automated tools can't catch everything—domain-specific secrets require domain-specific patterns.

The Solution

har-capture helps identify and remove common sensitive data patterns from HAR files while preserving their debugging value. Interactive review mode shows you what was flagged so you can verify before sharing. Extensible API lets you add custom patterns for your domain.

⚠️ Important: Use at Your Own Risk

har-capture is a development tool that helps identify common PII patterns. It is NOT a substitute for manual security review, domain-specific sanitization, or production security workflows.

This tool uses heuristics that cannot anticipate every pattern. Domain-specific secrets, proprietary formats, and unusual auth schemes may not be detected. You are responsible for verifying all sanitized output before sharing.

Always use interactive mode (--interactive) to review what was flagged. For production use, extend the detection patterns for your specific domain. Assume HAR files may still contain sensitive data after sanitization.

This tool reduces but does not eliminate the risk of PII exposure. Provided "as-is" under MIT License without warranty of any kind.

See It In Action

Basic Usage Comparison Interactive Review

Capture and automatically sanitize HAR files with a single command:

$ har-capture get http://localhost:8080/api/user -o demo.har

============================================================
HAR CAPTURE
============================================================

  Target:     http://localhost:8080/api/user
  Browser:    chromium
  Output:     demo.har

Checking connectivity...
  Connected:  http://localhost:8080/

Checking authentication type...
  Detected: Form-based or no auth required

============================================================
CAPTURE COMPLETE
============================================================

  Compressed: demo.sanitized.har.gz
  Sanitized:  demo.sanitized.har
  Removed 3 bloat entries (7 -> 4)

Next steps:
  • Share the file (PII removed): demo.sanitized.har.gz
  • Validate for secrets: har-capture validate demo.sanitized.har.gz

Validation

Verify HAR files are safe to share:

$ har-capture validate demo.sanitized.har.gz

[OK] demo.sanitized.har.gz: Clean

Summary: 0 errors, 0 warnings

See how sensitive data is automatically detected and removed:

Original (Unlabeled Pipe Data)

var deviceConfig = '
  NETGEAR-C7000|
  192.168.0.1|
  admin|
  TK421_1977!|
  MatrixNet-5G|
  sk_live_a8f2k9m3p7x1n6v4b2|
  SN827194729|
  WPA3|
  10.31.41.5
';
var systemInfo = '
  Router7|
  GRID_NET_2024|
  00:1A:2B:3C:4D:5E|
  enabled|
  tok_1982flynn
';

Sanitized (PII Removed)

var deviceConfig = '
  NETGEAR-C7000|
  10.255.186.84|
  admin|
  FIELD_a8b9c0d1|
  MatrixNet-5G|
  FIELD_7b609581|
  SN: SERIAL_c1673a31|
  WPA3|
  10.255.186.84
';
var systemInfo = '
  Router7|
  GRID_NET_2024|
  02:21:96:a3:9b:4b|
  enabled|
  FIELD_9d8e7f6g
';

When ambiguous values are detected (like unlabeled pipe-delimited data), har-capture prompts for manual review:

Interactive review mode showing flagged values for manual selection

Why It Matters

Security teams can share HAR files with vendors without exposing credentials.

Support teams can collect diagnostics from users safely and confidently.

Developers can automate HAR sanitization in CI/CD pipelines without dependencies.

One leaked API key can cost thousands in breach response. har-capture prevents that.

Key Features

Common PII detection (passwords, tokens, emails, IPs, MACs)
Format-preserving redaction (keeps valid test data)
Correlation-preserving hashes
Zero dependencies (stdlib only)
CLI and Python API
Interactive review mode for verification

Use Cases

Support teams collecting diagnostics from users
Security teams reviewing web traffic
Test automation with sensitive data
Bug reports requiring HAR files

Why har-capture?

Feature	har-capture	Google har-sanitizer	Manual Editing
Programmable (API/CLI)	✅	❌	❌
Format-preserving redaction	✅	❌	❌
Actively maintained	✅	❌ (Last updated 2017)	—
Zero dependencies	✅	❌ (Python 2.7, Flask, etc.)	—

Documentation

Full documentation available on GitHub

Learn more about the HAR specification

Installation

Install

pip install har-capture

Usage

CLI Python API

# Capture and sanitize with interactive review
har-capture get https://example.com --interactive -o sanitized.har.gz

# Or sanitize existing file
har-capture sanitize input.har -o clean.har

# Interactive review mode
har-capture sanitize input.har --interactive

from har_capture import sanitize_har
import json

# Sanitize HAR data
with open('input.har') as f:
    har_data = json.load(f)

clean_har = sanitize_har(har_data)

with open('clean.har', 'w') as f:
    json.dump(clean_har, f)

Ready to Share HAR Files Safely?

View on GitHub Install from PyPI