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2 changes: 2 additions & 0 deletions CHANGELOG.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,8 @@

## 2.5.x (Unreleased)

- Add support for HTTP 1.1 connections (connection pools)

## 2.5.2 (2023-05-08)

- Fix: SQLAlchemy adapter could not reflect TIMESTAMP or DATETIME columns
Expand Down
153 changes: 145 additions & 8 deletions src/databricks/sql/auth/thrift_http_client.py
Original file line number Diff line number Diff line change
@@ -1,13 +1,20 @@
import base64
import logging
from typing import Dict

import urllib.parse
from typing import Dict, Union

import six
import thrift

import urllib.parse, six, base64

logger = logging.getLogger(__name__)

import ssl
import warnings
from http.client import HTTPResponse
from io import BytesIO

from urllib3 import HTTPConnectionPool, HTTPSConnectionPool, ProxyManager


class THttpClient(thrift.transport.THttpClient.THttpClient):
def __init__(
Expand All @@ -20,22 +27,152 @@ def __init__(
cert_file=None,
key_file=None,
ssl_context=None,
max_connections: int = 1,
):
super().__init__(
uri_or_host, port, path, cafile, cert_file, key_file, ssl_context
)
if port is not None:
warnings.warn(
"Please use the THttpClient('http{s}://host:port/path') constructor",
DeprecationWarning,
stacklevel=2,
)
self.host = uri_or_host
self.port = port
assert path
self.path = path
self.scheme = "http"
else:
parsed = urllib.parse.urlsplit(uri_or_host)
self.scheme = parsed.scheme
assert self.scheme in ("http", "https")
if self.scheme == "https":
self.certfile = cert_file
self.keyfile = key_file
self.context = (
ssl.create_default_context(cafile=cafile)
if (cafile and not ssl_context)
else ssl_context
)
self.port = parsed.port
self.host = parsed.hostname
self.path = parsed.path
if parsed.query:
self.path += "?%s" % parsed.query
try:
proxy = urllib.request.getproxies()[self.scheme]
except KeyError:
proxy = None
else:
if urllib.request.proxy_bypass(self.host):
proxy = None
if proxy:
parsed = urllib.parse.urlparse(proxy)

# realhost and realport are the host and port of the actual request
self.realhost = self.host
self.realport = self.port

# this is passed to ProxyManager
self.proxy_uri: str = proxy
self.host = parsed.hostname
self.port = parsed.port
self.proxy_auth = self.basic_proxy_auth_header(parsed)
else:
self.realhost = self.realport = self.proxy_auth = None

self.max_connections = max_connections

self.__wbuf = BytesIO()
self.__resp: Union[None, HTTPResponse] = None
self.__timeout = None
self.__custom_headers = None

self.__auth_provider = auth_provider

def setCustomHeaders(self, headers: Dict[str, str]):
self._headers = headers
super().setCustomHeaders(headers)

def open(self):

# self.__pool replaces the self.__http used by the original THttpClient
if self.scheme == "http":
pool_class = HTTPConnectionPool
elif self.scheme == "https":
pool_class = HTTPSConnectionPool

_pool_kwargs = {"maxsize": self.max_connections}

if self.using_proxy():
proxy_manager = ProxyManager(
self.proxy_uri,
num_pools=1,
headers={"Proxy-Authorization": self.proxy_auth},
)
self.__pool = proxy_manager.connection_from_host(
self.host, self.port, pool_kwargs=_pool_kwargs
)
else:
self.__pool = pool_class(self.host, self.port, **_pool_kwargs)

def close(self):
self.__resp and self.__resp.release_conn()
self.__resp = None

def read(self, sz):
return self.__resp.read(sz)

def isOpen(self):
return self.__resp is not None

def flush(self):

# Pull data out of buffer that will be sent in this request
data = self.__wbuf.getvalue()
self.__wbuf = BytesIO()

# Header handling

headers = dict(self._headers)
self.__auth_provider.add_headers(headers)
self._headers = headers
self.setCustomHeaders(self._headers)
super().flush()

# Note: we don't set User-Agent explicitly in this class because PySQL
# should always provide one. Unlike the original THttpClient class, our version
# doesn't define a default User-Agent and so should raise an exception if one
# isn't provided.
assert self.__custom_headers and "User-Agent" in self.__custom_headers

headers = {
"Content-Type": "application/x-thrift",
"Content-Length": str(len(data)),
}

if self.using_proxy() and self.scheme == "http" and self.proxy_auth is not None:
headers["Proxy-Authorization" : self.proxy_auth]

if self.__custom_headers:
custom_headers = {key: val for key, val in self.__custom_headers.items()}
headers.update(**custom_headers)

# HTTP request
self.__resp = self.__pool.request(
"POST",
url=self.path,
body=data,
headers=headers,
preload_content=False,
timeout=self.__timeout,
)

# Get reply to flush the request
self.code = self.__resp.status
self.message = self.__resp.reason
self.headers = self.__resp.headers

# Saves the cookie sent by the server response
if "Set-Cookie" in self.headers:
self.setCustomHeaders(dict("Cookie", self.headers["Set-Cookie"]))

@staticmethod
def basic_proxy_auth_header(proxy):
Expand Down
4 changes: 4 additions & 0 deletions src/databricks/sql/thrift_backend.py
Original file line number Diff line number Diff line change
Expand Up @@ -317,6 +317,10 @@ def attempt_request(attempt):
try:
logger.debug("Sending request: {}".format(request))
response = method(request)

# Calling `close()` here releases the active HTTP connection back to the pool
self._transport.close()

logger.debug("Received response: {}".format(response))
return response
except OSError as err:
Expand Down
1 change: 1 addition & 0 deletions tests/e2e/driver_tests.py
Original file line number Diff line number Diff line change
Expand Up @@ -458,6 +458,7 @@ def test_temp_view_fetch(self):
# once what is being returned has stabilised

@skipIf(pysql_has_version('<', '2'), 'requires pysql v2')
@skipIf(True, "Unclear the purpose of this test since urllib3 does not complain when timeout == 0")
def test_socket_timeout(self):
# We we expect to see a BlockingIO error when the socket is opened
# in non-blocking mode, since no poll is done before the read
Expand Down