AnyRFC

Complete, RFC-compliant protocol clients built with AnyIO structured concurrency

AnyRFC provides RFC-compliant protocol clients that prioritize correctness, security, and modern async patterns. Built exclusively with AnyIO for structured concurrency.

Why AnyRFC?

🎯 RFC Compliance First - Every implementation passes comprehensive RFC test suites
⚡ Modern Async - Structured concurrency with AnyIO (no asyncio dependency hell)
🔒 Security by Default - TLS everywhere, proper certificate validation, secure authentication
🧪 Battle-Tested - Real-world interoperability testing against major servers
📝 Type Safe - Full mypy compliance with strict typing
🚀 Complete - Full implementations, not toys or demos

Quick Start

pip install anyrfc

import anyio
from anyrfc import WebSocketClient

async def main():
    async with WebSocketClient("wss://echo.websocket.org/") as ws:
        await ws.send_text("Hello, AnyRFC!")
        async for message in ws.receive():
            print(f"Received: {message}")
            break  # Just get the first message

anyio.run(main)

What's Included

🌐 WebSocket Client (RFC 6455)

Complete WebSocket implementation with all RFC 6455 features:

from anyrfc import WebSocketClient, CloseCode

async with WebSocketClient("wss://api.example.com/ws") as ws:
    # Send different message types
    await ws.send_text("Hello!")
    await ws.send_binary(b"\\x00\\x01\\x02\\x03")

    # Handle incoming messages
    async for message in ws.receive():
        if isinstance(message, str):
            print(f"Text: {message}")
        else:
            print(f"Binary: {message.hex()}")

        if should_close:
            await ws.close(CloseCode.NORMAL_CLOSURE)
            break

Features:

• ✅ All frame types (text, binary, ping, pong, close)
• ✅ Message fragmentation and reassembly
• ✅ Proper client-side frame masking
• ✅ Extension support framework
• ✅ Graceful connection handling
• ✅ Real-server compatibility

📧 Email Clients (IMAP & SMTP)

Battle-tested email clients with full RFC compliance and real-world Gmail compatibility:

from anyrfc import IMAPClient, SMTPClient

# IMAP - Complete email operations
async with IMAPClient("imap.gmail.com", use_tls=True) as imap:
    await imap.authenticate({"username": "user", "password": "app_password"})
    await imap.select_mailbox("INBOX")

    # Search and read emails
    messages = await imap.search_messages("UNSEEN")
    for msg_id in messages[:5]:
        email = await imap.fetch_messages(str(msg_id), "BODY[]")
        
        # Mark as read
        await imap.store_message_flags(str(msg_id), [b"\\Seen"], "FLAGS")

    # Create drafts with proper literal continuation
    await imap.append_message("Drafts", email_content, [b"\\Draft"])

    # Extract attachments as binary BLOBs
    bodystructure = await imap.fetch_messages(str(msg_id), "BODYSTRUCTURE")
    # Parse structure and fetch binary parts...

# SMTP - Send emails with authentication
async with SMTPClient("smtp.gmail.com", use_starttls=True) as smtp:
    await smtp.authenticate({"username": "user", "password": "app_password"})
    await smtp.send_message(
        from_addr="sender@example.com",
        to_addrs=["recipient@example.com"],
        message="""Subject: Hello from AnyRFC!

This email was sent using AnyRFC's SMTP client!
"""
    )

IMAP Features (RFC 9051 Compliant):

• ✅ Complete email operations: Read, flag, search, delete
• ✅ Draft creation: APPEND with proper literal continuation
• ✅ Real-time monitoring: Live email detection with polling
• ✅ Attachment extraction: Binary BLOB downloads (PDFs, images, etc.)
• ✅ Gmail compatibility: Tested with live Gmail IMAP servers
• ✅ Extension support: IDLE, SORT, THREAD, CONDSTORE, QRESYNC
• ✅ Battle-tested: Handles 178KB+ attachments and complex operations

Architecture Highlights

AnyIO Structured Concurrency

Every I/O operation uses AnyIO's structured concurrency primitives:

async def websocket_with_timeout():
    async with anyio.create_task_group() as tg:
        # Connection with automatic cleanup
        tg.start_soon(websocket_handler)

        # Heartbeat with cancellation scope
        with anyio.move_on_after(30):
            tg.start_soon(heartbeat_sender)

RFC Compliance Testing

from anyrfc.websocket import WebSocketClient

client = WebSocketClient("wss://example.com")
compliance_report = await client.validate_compliance()

# Returns detailed RFC 6455 test results
assert compliance_report["handshake_validation"] == True
assert compliance_report["frame_parsing"] == True
assert compliance_report["close_sequence"] == True

Type Safety

from anyrfc import WebSocketClient
from anyrfc.websocket import WSFrame, OpCode

# Fully typed interfaces
client: WebSocketClient = WebSocketClient("wss://api.example.com")
frame: WSFrame = WSFrame(fin=True, opcode=OpCode.TEXT, payload=b"test")

# MyPy validates everything
reveal_type(client.websocket_state)  # WSState
reveal_type(await client.receive())  # Union[str, bytes]

Installation & Setup

Basic Installation

pip install anyrfc

Development Setup

git clone https://github.com/elgertam/anyrfc.git
cd anyrfc

# Install with uv (recommended)
uv sync --all-extras

# Or with pip
pip install -e ".[dev]"

Requirements

• Python: 3.11+
• Core: anyio>=4.0.0
• HTTP: httpx>=0.25.0 (approved dependency)
• Types: typing-extensions>=4.0.0

Real-World Examples

WebSocket Trading Client

from anyrfc import WebSocketClient
import json

async def crypto_prices():
    # Binance public data stream (no authentication required)
    uri = "wss://data-stream.binance.vision/ws/btcusdt@ticker"

    # Use relaxed validation for real-world servers
    async with WebSocketClient(uri, strict_rfc_validation=False) as ws:
        async for message in ws.receive():
            data = json.loads(message)
            if 'c' in data:  # Current price
                price = float(data['c'])
                change = float(data['P'])  # 24hr change %
                print(f"💰 BTC-USDT: ${price:,.2f} ({change:+.2f}%)")

Email Monitoring Service

from anyrfc import IMAPClient
import anyio
import re

async def email_monitor():
    """Real-time email monitoring with secret code extraction."""
    async with IMAPClient("imap.gmail.com", use_tls=True) as imap:
        await imap.authenticate({"username": "user", "password": "app_password"})
        await imap.select_mailbox("INBOX")

        while True:
            # Check for new emails every 5 seconds (production-tested)
            unread = await imap.search_messages("UNSEEN")
            if unread:
                print(f"📧 {len(unread)} new emails!")
                
                for msg_id in unread:
                    # Fetch email content
                    email_data = await imap.fetch_messages(str(msg_id), "BODY[]")
                    email_text = email_data[str(msg_id)][b"BODY[]"].decode()
                    
                    # Extract verification codes (6 digits)
                    codes = re.findall(r'\b\d{6}\b', email_text)
                    if codes:
                        print(f"🔐 Verification code found: {codes[0]}")
                    
                    # Mark as read
                    await imap.store_message_flags(str(msg_id), [b"\\Seen"], "FLAGS")

            await anyio.sleep(5)  # 5-second polling proven effective

Testing & Quality

Comprehensive Test Suite

# Run all tests
uv run pytest

# RFC compliance tests
uv run pytest tests/rfc_compliance/ -v

# Real-server interoperability
uv run pytest tests/interop/ -v

# Type checking
uv run mypy src/

# Linting
uv run ruff check src/

Real-Server Testing

AnyRFC is extensively tested against production servers:

• ✅ WebSocket: echo.websocket.org, Binance WebSocket API, major services
• ✅ IMAP: Live Gmail operations (read, flag, drafts, attachments)
• ✅ SMTP: Gmail, SendGrid, major SMTP services
• ✅ Production verified: Real-time email monitoring, 178KB+ file transfers
• ✅ Compliance tested: Autobahn WebSocket suite, RFC test vectors

Protocol Roadmap

✅ Phase 1: WebSocket Foundation (Complete)

• WebSocket Client (RFC 6455)
• Autobahn test suite compliance
• Real-world server compatibility

✅ Phase 2: Email Infrastructure (Complete)

• IMAP Client (RFC 9051)
  • Complete email operations (read, flag, search, delete)
  • Draft creation with literal continuation
  • Attachment extraction (binary BLOBs)
  • Real-time email monitoring
  • Gmail production testing
  • Extensions: IDLE, SORT, THREAD, CONDSTORE, QRESYNC
• SMTP Client Foundation (RFC 5321)
• SASL authentication framework (RFC 4422)

🚧 Phase 3: OAuth & Modern Auth (In Progress)

• OAuth 2.0 client (RFC 6749/6750)
• JWT handling (RFC 7519)
• PKCE support (RFC 7636)
• Device authorization flow (RFC 8628)
• MIME message composition (RFC 2045-2049)
• Advanced SMTP features (DKIM, SPF validation)

🔮 Phase 4: Advanced Protocols

• SSH client suite (RFC 4251-4254)
• SFTP file transfer
• DNS-over-HTTPS (RFC 8484)
• CoAP for IoT (RFC 7252)

Performance

AnyRFC is built for high-performance workloads:

# Concurrent WebSocket connections
async def stress_test():
    async with anyio.create_task_group() as tg:
        for i in range(100):
            tg.start_soon(websocket_worker, f"wss://api{i}.example.com")

# Memory-efficient message streaming
async def large_mailbox():
    async with IMAPClient("imap.example.com") as imap:
        # Stream large mailboxes without loading everything into memory
        async for message in imap.fetch_messages("1:*", "BODY[]"):
            await process_message(message)  # Process one at a time

Contributing

We welcome contributions! AnyRFC follows strict quality standards:

1. RFC Compliance: All features must be RFC-compliant
2. AnyIO Only: No asyncio imports allowed
3. Type Safety: Full mypy compliance required
4. Real-World Testing: Test against actual servers
5. Security First: Secure by default

See CONTRIBUTING.md for detailed guidelines.

Security

• 🔒 TLS Everywhere: Secure connections by default
• 🛡️ Input Validation: Strict RFC-compliant parsing
• 🔐 Credential Safety: Never logs or stores credentials insecurely
• 📋 Security Audits: Regular dependency and code security reviews

Report security issues to: andrew@elgert.org

License

MIT License - see LICENSE for details.

Why "AnyRFC"?

Any + RFC = Protocol clients that work with any server implementing the RFC standard. Built on AnyIO for structured concurrency.

Built by Andrew M. Elgert • Documentation • Issues • PyPI