Using Proxies in Python with httpx

Using Proxies in Python with httpx

httpx and Proxies

httpx is a modern HTTP library for Python that supports both synchronous and asynchronous modes of operation. A key advantage is its built-in support for HTTP/2 and SOCKS proxies without additional libraries.

Installation

pip install httpx
# For SOCKS support:
pip install httpx[socks]
# For HTTP/2:
pip install httpx[http2]

Synchronous Mode

HTTP Proxy

import httpx

proxy = "http://user:pass@proxy_ip:port"
response = httpx.get("https://httpbin.org/ip", proxy=proxy)
print(response.json())

Different Proxies for HTTP and HTTPS

proxies = {
    "http://": "http://proxy1:port",
    "https://": "http://proxy2:port",
}

with httpx.Client(proxy=proxies) as client:
    response = client.get("https://httpbin.org/ip")
    print(response.json())

SOCKS5 Proxy

import httpx

proxy = "socks5://user:pass@proxy_ip:port"
with httpx.Client(proxy=proxy) as client:
    response = client.get("https://httpbin.org/ip")
    print(response.json())

Asynchronous Mode

Basic Example

import httpx
import asyncio

async def fetch():
    proxy = "http://user:pass@proxy_ip:port"
    async with httpx.AsyncClient(proxy=proxy) as client:
        response = await client.get("https://httpbin.org/ip")
        print(response.json())

asyncio.run(fetch())

Parallel Requests

import httpx
import asyncio

async def fetch_url(client, url):
    try:
        response = await client.get(url, timeout=10)
        return response.text
    except Exception as e:
        return None

async def main():
    proxy = "http://user:pass@proxy_ip:port"
    urls = [f"https://example.com/page/{i}" for i in range(50)]

    async with httpx.AsyncClient(proxy=proxy) as client:
        tasks = [fetch_url(client, url) for url in urls]
        results = await asyncio.gather(*tasks)
        success = sum(1 for r in results if r)
        print(f"Success: {success}/{len(urls)}")

asyncio.run(main())

HTTP/2 via Proxy

httpx is one of the few Python libraries with HTTP/2 support:

import httpx

proxy = "http://user:pass@proxy_ip:port"
with httpx.Client(proxy=proxy, http2=True) as client:
    response = client.get("https://httpbin.org/ip")
    print(f"HTTP version: {response.http_version}")
    print(response.json())

HTTP/2 via proxy works through the CONNECT method — the proxy creates a TCP tunnel through which an HTTP/2 connection to the server is established.

Proxy Rotation

import httpx
import random

PROXIES = [
    "http://user:pass@proxy1:port",
    "http://user:pass@proxy2:port",
    "http://user:pass@proxy3:port",
]

def get_random_proxy():
    return random.choice(PROXIES)

# Synchronous rotation
for i in range(10):
    proxy = get_random_proxy()
    with httpx.Client(proxy=proxy) as client:
        resp = client.get("https://httpbin.org/ip")
        print(resp.json())

Asynchronous Rotation

import httpx
import asyncio
import random

PROXIES = [
    "http://user:pass@proxy1:port",
    "http://user:pass@proxy2:port",
    "http://user:pass@proxy3:port",
]

async def fetch_with_rotation(url):
    proxy = random.choice(PROXIES)
    async with httpx.AsyncClient(proxy=proxy) as client:
        try:
            resp = await client.get(url, timeout=10)
            return resp.text
        except Exception:
            return None

async def main():
    urls = ["https://example.com"] * 20
    tasks = [fetch_with_rotation(url) for url in urls]
    results = await asyncio.gather(*tasks)
    print(f"Success: {sum(1 for r in results if r)}")

asyncio.run(main())

Client Configuration

Timeout

timeout = httpx.Timeout(
    connect=5.0,    # connection to proxy and server
    read=10.0,      # reading the response
    write=5.0,      # sending the request
    pool=5.0        # waiting in the connection pool
)

client = httpx.Client(proxy=proxy, timeout=timeout)

Headers and Cookies

headers = {
    "User-Agent": "Mozilla/5.0 ...",
    "Accept-Language": "en-US,en;q=0.9",
}

client = httpx.Client(
    proxy=proxy,
    headers=headers,
    follow_redirects=True,
    max_redirects=10
)

Connection Pool

limits = httpx.Limits(
    max_connections=100,          # total connections
    max_keepalive_connections=20  # keep-alive connections
)

client = httpx.AsyncClient(proxy=proxy, limits=limits)

Error Handling

import httpx

async def safe_fetch(client, url):
    try:
        response = await client.get(url)
        response.raise_for_status()
        return response.text
    except httpx.ProxyError as e:
        print(f"Proxy error: {e}")
    except httpx.ConnectTimeout:
        print("Connection timeout")
    except httpx.ReadTimeout:
        print("Read timeout")
    except httpx.HTTPStatusError as e:
        print(f"HTTP {e.response.status_code}")
    except httpx.RequestError as e:
        print(f"Request error: {e}")
    return None

httpx vs requests vs aiohttp

Migration from requests

httpx is designed as a drop-in replacement for requests. Migration is minimal:

# requests
import requests
resp = requests.get(url, proxies={"https": proxy})

# httpx
import httpx
resp = httpx.get(url, proxy=proxy)

The main difference: in httpx, the proxy parameter (singular) is used instead of proxies.

Conclusion

httpx is the best choice for new Python projects requiring proxy functionality. Its built-in support for HTTP/2, SOCKS5, and both synchronous and asynchronous modes makes it a versatile tool. The requests-compatible API simplifies migration for existing projects.