A command-line tool to check if domains are filtered (blocked) in Iran by analyzing DNS responses.

This tool checks if a domain is blocked by Iranian ISPs by:

1. Resolving the domain's A record using DNS
2. Comparing the resolved IP addresses against known blocking IPs used by Iranian ISPs
3. Reporting whether the domain is blocked or accessible

Note: This tool can only detect DNS-based blocking and does not have the power to detect other types of filtering or network disorders.

• 🚀 Fast async DNS resolution - Check multiple domains concurrently
• 📋 Multiple input methods - Single domain, comma-separated list, or file
• 🎨 Beautiful CLI output - Rich formatted tables with live updates
• 🔧 Configurable - Custom DNS servers and timeout settings

• Python 3.10+

pip install check-filter

git clone https://github.com/hatamiarash7/CheckFiltering.git cd CheckFiltering poetry install

You can also download the wheel package from the release page.

check-filter domain github.com

check-filter domains github.com,google.com,twitter.com

Create a file with domain names (one per line). Lines starting with # are treated as comments:

# Social media github.com twitter.com facebook.com # Development gitlab.com stackoverflow.com 

Then run:

check-filter file domains.txt

check-filter --version # or check-filter -v

check-filter --help check-filter domain --help check-filter domains --help check-filter file --help

import asyncio from check_filter import DomainChecker, FilterStatus async def main(): checker = DomainChecker() # Check a single domain result = await checker.acheck("google.com") print(f"{result.domain}: {result.status.value}") print(f"Blocked: {result.is_blocked}") print(f"IPs: {result.ips}") # Check multiple domains concurrently results = await checker.acheck_many([ "google.com", "twitter.com", "github.com", ]) for result in results: status = "🚫 Blocked" if result.is_blocked else "✅ Free" print(f"{result.domain}: {status}") asyncio.run(main())

from check_filter import DomainChecker # Use custom blocked IPs and DNS servers checker = DomainChecker( blocked_ips={"10.10.34.34", "10.10.34.35"}, nameservers=["8.8.8.8", "8.8.4.4"], timeout=10.0, )

from check_filter import CheckResult, FilterStatus # CheckResult is a dataclass with useful properties result = await checker.acheck("example.com") # Access properties print(result.domain) # "example.com" print(result.status) # FilterStatus.FREE print(result.is_free) # True print(result.is_blocked) # False print(result.ips) # frozenset({'93.184.216.34'}) print(result.error) # None (or error message if failed) # Backward compatible tuple unpacking domain, is_free = result

# Clone the repository git clone https://github.com/hatamiarash7/CheckFiltering.git cd CheckFiltering # Install dependencies with dev tools make install-dev

make help # Show all available commands make test # Run tests make test-cov # Run tests with coverage report make lint # Run all linters make lint-fix # Run linters with auto-fix make format # Format code with black and isort make type-check # Run type checking with mypy make check # Run all checks (format, lint, type-check, test) make build # Build package make clean # Clean build artifacts

# Run all tests make test # Run tests with coverage make test-cov # Run fast tests (exclude slow/integration tests) make test-fast

Main class for checking domain filtering status.

DomainChecker( blocked_ips: Set[str] | None = None, # Custom blocked IPs nameservers: list[str] | None = None, # DNS servers to use timeout: float = 5.0, # DNS query timeout )

Methods:

• acheck(domain: str) -> CheckResult - Check a single domain
• acheck_many(domains: list[str]) -> list[CheckResult] - Check multiple domains

Dataclass containing the result of a domain check.

Attributes:

• domain: str - The checked domain
• status: FilterStatus - The filtering status
• ips: frozenset[str] - Resolved IP addresses
• error: str | None - Error message if check failed

Properties:

• is_blocked: bool - True if domain is blocked
• is_free: bool - True if domain is not blocked

Enum with possible filtering statuses:

• FREE - Domain is accessible
• BLOCKED - Domain is blocked
• ERROR - Check failed (timeout, etc.)
• UNKNOWN - Domain doesn't exist (NXDOMAIN)

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch: git checkout -b feature/my-new-feature
3. Install development dependencies: make install-dev
4. Make your changes and add tests
5. Run checks: make check
6. Commit your changes: git commit -am 'Add some feature'
7. Push to the branch: git push origin feature/my-new-feature
8. Submit a pull request

Found a bug or have a suggestion? Please open an issue.

This project is licensed under the MIT License - see the LICENSE file for details.