Database Connection String with Credentials Regex for Python

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching database connection string with credentials, ported and verified for Python. In security-sensitive code, using an unverified regex can open the door to both false positives and denial-of-service attacks. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

# Database Connection String with Credentials
# ReDoS-safe | RegexVault — Security > Secrets & Config

import re

database_connection_string_with_credentials_pattern = re.compile(r'^(postgres(?:ql)?|mysql|mongodb(?:\+srv)?|redis|mssql|sqlserver|mariadb|oracle):\/\/([^:]+):([^@]+)@([^/?]+)(?:\/([^?]+))?(?:\?(.+))?$')

def validate_database_connection_string_with_credentials(value: str) -> bool:
    return bool(database_connection_string_with_credentials_pattern.fullmatch(value))

# Example
print(validate_database_connection_string_with_credentials("postgresql://user:password@localhost:5432/mydb"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Security > Secrets & Config category and carries a ReDoS-safe certification. That matters for Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Capture groups: 1=scheme, 2=username, 3=password, 4=host:port, 5=database, 6=query params. Passwords may be URL-encoded (e.g., P%40ssw0rd). Extract and rotate any credentials found in this format in code or config files.