httpx

Warnings

• breaking proxies= argument was removed in 0.28.0. Using it raises TypeError.
  Fix: Use proxy='http://...' for a single proxy, or mounts={'https://': httpx.HTTPTransport(proxy='...')} for per-scheme configuration.
• breaking app= shortcut argument was removed in 0.28.0. It was deprecated in 0.27.0.
  Fix: Use transport=httpx.WSGITransport(app=app) or transport=httpx.ASGITransport(app=app) explicitly.
• breaking Redirects are NOT followed by default (changed in 0.20.0). Requests that previously auto-redirected now return the 3xx response directly.
  Fix: Pass follow_redirects=True per-request or at the Client level: httpx.Client(follow_redirects=True).
• deprecated verify='path/to/ca-bundle' (string) and cert=('cert', 'key') arguments are deprecated in 0.28.0 and will raise DeprecationWarning.
  Fix: Build an ssl.SSLContext manually and pass it via verify=ssl_context. See https://www.python-httpx.org/advanced/ssl/
• gotcha httpx is pre-1.0. Minor version bumps (e.g. 0.27 → 0.28) can and do introduce breaking changes. The maintainers recommend pinning the minor version.
  Fix: Pin with httpx>=0.28.1,<0.29 in requirements. Review the CHANGELOG before upgrading.
• gotcha HTTP/2 is disabled by default. Installing httpx alone does not enable it.
  Fix: pip install 'httpx[http2]' then pass http2=True: httpx.Client(http2=True)
• gotcha Top-level functions (httpx.get, httpx.post, etc.) open a new TCP connection on every call. For more than one request to the same host this is inefficient.
  Fix: Use httpx.Client() or httpx.AsyncClient() as a context manager for connection pooling, keep-alive, and shared configuration.

Install

• pip install httpx Core (HTTP/1.1 only)
• pip install 'httpx[http2]' With HTTP/2 support
• pip install 'httpx[cli]' With command-line client
• pip install 'httpx[brotli]' With Brotli decoding
• pip install 'httpx[zstd]' With Zstandard decoding

Imports

• httpx

  import httpx

  Top-level module import. All public symbols (Client, AsyncClient, Request, Response, etc.) are available under httpx.*
• httpx.Client

  with httpx.Client() as client:
      r = client.get('https://example.com')

  Always use Client as a context manager (with statement) to ensure connections are properly closed and pooled.
• httpx.AsyncClient

  async with httpx.AsyncClient() as client:
      r = await client.get('https://example.com')

  Always use AsyncClient as an async context manager. Failing to do so leaks connections. Do not instantiate a new AsyncClient per request — reuse one instance.
• httpx.Timeout

  httpx.Client(timeout=httpx.Timeout(5.0, connect=2.0))

  Passing a plain number sets all timeout phases equally. Use httpx.Timeout() for granular control of connect, read, write, and pool timeouts.
• httpx.BasicAuth / httpx.Auth

  httpx.Client(auth=('user', 'pass'))
  # or
  httpx.Client(auth=httpx.BasicAuth('user', 'pass'))

  Auth can be a (user, pass) tuple or an httpx.Auth subclass. NetRC auth is no longer automatic; use httpx.NetRCAuth() explicitly.

Quickstart

Minimal sync and async HTTP GET requests using httpx 0.28.x. Uses Client/AsyncClient as context managers for proper connection management.

import httpx

# One-off request (new connection each time — fine for scripts)
r = httpx.get('https://httpbin.org/get', timeout=10.0)
r.raise_for_status()
print(r.status_code)       # 200
print(r.json())            # parsed JSON body

# Recommended: reuse a Client for multiple requests (connection pooling)
with httpx.Client(base_url='https://httpbin.org', timeout=10.0) as client:
    resp = client.get('/get', params={'key': 'value'})
    resp.raise_for_status()
    print(resp.json())

# Async variant
import asyncio

async def main():
    async with httpx.AsyncClient(base_url='https://httpbin.org', timeout=10.0) as client:
        resp = await client.get('/get')
        resp.raise_for_status()
        print(resp.json())

asyncio.run(main())