Log-Obfuscator

Before submitting user logs (such as Nginx logs or application error logs) to analysis tools or third parties for debugging, it is essential to remove sensitive information (IP addresses, emails, credit card numbers). Manually editing large log files is time-consuming and unsafe.

🚀 Tool Idea: Log-Obfuscator

Features

• Accepts a log file path or directory.
• Identifies and obfuscates sensitive data using built-in or user-provided regular expression patterns, without affecting the log structure.
  (For example, replaces IP addresses with [IP_REDACTED], emails with [EMAIL_REDACTED].)
• Outputs the obfuscated logs to a new file or stream.

User Pain Point Solved

Automates the critical step of data privacy and compliance, ensuring sensitive information is not leaked to debugging environments or analysis services.

Why Node.js

Node.js provides excellent stream processing capabilities, allowing efficient handling of very large log files (GB-level) without loading the entire file into memory.

Usage

Install

Clone this repo or copy the tool directory, then install dependencies if needed:

npm install

Command Line

node index.js <input> [options]

Or, if you add a bin entry and install globally:

log-obfuscator <input> [options]

Arguments

• <input>: Path to a log file or directory to process.

Options

• -o, --output <output>: Output file or directory. If not specified, output will be printed to stdout.
• -p, --patterns <patternFile>: Path to a custom patterns JSON file for additional or custom obfuscation rules.

Examples

Obfuscate a single log file and print to console:

node index.js example.log

Obfuscate a log file and write to a new file:

node index.js example.log -o obfuscated.log

Obfuscate all logs in a directory and output to another directory:

node index.js ./logs -o ./logs-obfuscated

Use custom patterns:

node index.js example.log -p my-patterns.json -o obfuscated.log

Custom Patterns File Example

my-patterns.json:

[
  {
    "name": "Phone Number",
    "regex": "\\b\\d{3}[-.]?\\d{3}[-.]?\\d{4}\\b",
    "replacement": "[PHONE_REDACTED]"
  }
]

Example

Input:

2023-10-08 12:00:01 INFO User login from 192.168.1.10, email: [email protected]
2023-10-08 12:01:15 ERROR Payment failed for user [email protected], card: 4111 1111 1111 1111

Output:

2023-10-08 12:00:01 INFO User login from [IP_REDACTED], email: [EMAIL_REDACTED]
2023-10-08 12:01:15 ERROR Payment failed for user [EMAIL_REDACTED], card: [CREDIT_CARD_REDACTED]