httpx 环境变量

可以通过环境变量配置HTTPX库。默认情况下使用环境变量。要忽略环境变量，必须将​trust_env​设置为​False​。有两种方法可以设置​trust_env​以禁用环境变量：

• 在​client​上，通过 ​httpx.Client(trust_env=False)​。
• 使用顶级 API，例如 ​httpx.get("<url>", trust_env=False)​。

以下是HTTPX识别的环境变量列表以及它们所服务的功能：

HTTPX_LOG_LEVEL

有效值：​debug​、​trace​（不区分大小写）

如果设置为 ​debug​，则 HTTP 请求将记录到​stderr ​。这对于网络活动的常规用途报告非常有用。

如果设置为​trace ​，则除了调试日志行之外，有关执行 HTTP 请求的低级详细信息将被记录到​stderr ​。这可以帮助您调试问题，并查看通过网络发送的确切内容以及发送到哪个位置。

例：

# test_script.py
import httpx

with httpx.Client() as client:
    r = client.get("https://google.com")

调试输出：

$ HTTPX_LOG_LEVEL=debug python test_script.py
DEBUG [2019-11-06 19:11:24] httpx._client - HTTP Request: GET https://google.com "HTTP/1.1 301 Moved Permanently"
DEBUG [2019-11-06 19:11:24] httpx._client - HTTP Request: GET https://www.google.com/ "HTTP/1.1 200 OK"

跟踪输出：

$ HTTPX_LOG_LEVEL=trace python test_script.py
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection_pool - acquire_connection origin=Origin(scheme='https' host='google.com' port=443)
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection_pool - new_connection connection=HTTPConnection(origin=Origin(scheme='https' host='google.com' port=443))
TRACE [2019-11-06 19:18:56] httpx._config - load_ssl_context verify=True cert=None trust_env=True http_versions=HTTPVersionConfig(['HTTP/1.1', 'HTTP/2'])
TRACE [2019-11-06 19:18:56] httpx._config - load_verify_locations cafile=/Users/florimond/Developer/python-projects/httpx/venv/lib/python3.8/site-packages/certifi/cacert.pem
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection - start_connect host='google.com' port=443 timeout=Timeout(timeout=5.0)
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection - connected http_version='HTTP/2'
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - send_headers stream_id=1 method='GET' target='/' headers=[(b':method', b'GET'), (b':authority', b'google.com'), (b':scheme', b'https'), (b':path', b'/'), (b'user-agent', b'python-httpx/0.7.6'), (b'accept', b'*/*'), (b'accept-encoding', b'gzip, deflate, br'), (b'connection', b'keep-alive')]
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - end_stream stream_id=1
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<RemoteSettingsChanged changed_settings:{ChangedSetting(setting=SettingCodes.MAX_CONCURRENT_STREAMS, original_value=None, new_value=100), ChangedSetting(setting=SettingCodes.INITIAL_WINDOW_SIZE, original_value=65535, new_value=1048576), ChangedSetting(setting=SettingCodes.MAX_HEADER_LIST_SIZE, original_value=None, new_value=16384)}>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<WindowUpdated stream_id:0, delta:983041>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<SettingsAcknowledged changed_settings:{}>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=1 event=<ResponseReceived stream_id:1, headers:[(b':status', b'301'), (b'location', b'https://www.google.com/'), (b'content-type', b'text/html; charset=UTF-8'), (b'date', b'Wed, 06 Nov 2019 18:18:56 GMT'), (b'expires', b'Fri, 06 Dec 2019 18:18:56 GMT'), (b'cache-control', b'public, max-age=2592000'), (b'server', b'gws'), (b'content-length', b'220'), (b'x-xss-protection', b'0'), (b'x-frame-options', b'SAMEORIGIN'), (b'alt-svc', b'quic=":443"; ma=2592000; v="46,43",h3-Q050=":443"; ma=2592000,h3-Q049=":443"; ma=2592000,h3-Q048=":443"; ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000')]>
DEBUG [2019-11-06 19:18:56] httpx._client - HTTP Request: GET https://google.com "HTTP/2 301 Moved Permanently"
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection_pool - acquire_connection origin=Origin(scheme='https' host='www.google.com' port=443)
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection_pool - new_connection connection=HTTPConnection(origin=Origin(scheme='https' host='www.google.com' port=443))
TRACE [2019-11-06 19:18:56] httpx._config - load_ssl_context verify=True cert=None trust_env=True http_versions=HTTPVersionConfig(['HTTP/1.1', 'HTTP/2'])
TRACE [2019-11-06 19:18:56] httpx._config - load_verify_locations cafile=/Users/florimond/Developer/python-projects/httpx/venv/lib/python3.8/site-packages/certifi/cacert.pem
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection - start_connect host='www.google.com' port=443 timeout=Timeout(timeout=5.0)
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection - connected http_version='HTTP/2'
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - send_headers stream_id=1 method='GET' target='/' headers=[(b':method', b'GET'), (b':authority', b'www.google.com'), (b':scheme', b'https'), (b':path', b'/'), (b'user-agent', b'python-httpx/0.7.6'), (b'accept', b'*/*'), (b'accept-encoding', b'gzip, deflate, br'), (b'connection', b'keep-alive')]
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - end_stream stream_id=1
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<RemoteSettingsChanged changed_settings:{ChangedSetting(setting=SettingCodes.MAX_CONCURRENT_STREAMS, original_value=None, new_value=100), ChangedSetting(setting=SettingCodes.INITIAL_WINDOW_SIZE, original_value=65535, new_value=1048576), ChangedSetting(setting=SettingCodes.MAX_HEADER_LIST_SIZE, original_value=None, new_value=16384)}>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<WindowUpdated stream_id:0, delta:983041>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<SettingsAcknowledged changed_settings:{}>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=1 event=<ResponseReceived stream_id:1, headers:[(b':status', b'200'), (b'date', b'Wed, 06 Nov 2019 18:18:56 GMT'), (b'expires', b'-1'), (b'cache-control', b'private, max-age=0'), (b'content-type', b'text/html; charset=ISO-8859-1'), (b'p3p', b'CP="This is not a P3P policy! See g.co/p3phelp for more info."'), (b'content-encoding', b'gzip'), (b'server', b'gws'), (b'content-length', b'5073'), (b'x-xss-protection', b'0'), (b'x-frame-options', b'SAMEORIGIN'), (b'set-cookie', b'1P_JAR=2019-11-06-18; expires=Fri, 06-Dec-2019 18:18:56 GMT; path=/; domain=.google.com; SameSite=none'), (b'set-cookie', b'NID=190=m8G9qLxCz2_4HbZI02ON2HTJF4xTvOhoJiS57Hm-OJrNS2eY20LfXMR_u-mLjujeshW5-BTezI69OGpHksT4ZK2TCDsWeU0DF7AmDTjjXFOdj30eIUTpNq7r9aWRvI8UrqiwlIsLkE8Ee3t5PiIiVdSMUcji7dkavGlMUpkMXU8; expires=Thu, 07-May-2020 18:18:56 GMT; path=/; domain=.google.com; HttpOnly'), (b'alt-svc', b'quic=":443"; ma=2592000; v="46,43",h3-Q050=":443"; ma=2592000,h3-Q049=":443"; ma=2592000,h3-Q048=":443"; ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000')]>
DEBUG [2019-11-06 19:18:56] httpx._client - HTTP Request: GET https://www.google.com/ "HTTP/2 200 OK"
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=1 event=<DataReceived stream_id:1, flow_controlled_length:5186, data:1f8b08000000000002ffc55af97adb4692ff3f4f>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=1 event=<DataReceived stream_id:1, flow_controlled_length:221, data:>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=1 event=<StreamEnded stream_id:1>
TRACE [2019-11-06 19:18:56] httpx._dispatch.http2 - receive_event stream_id=0 event=<PingReceived ping_data:0000000000000000>
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection_pool - release_connection connection=HTTPConnection(origin=Origin(scheme='https' host='www.google.com' port=443))
TRACE [2019-11-06 19:18:56] httpx._dispatch.connection - close_connection

SSLKEYLOGFILE

有效值：文件名

如果设置了此环境变量，则每当生成或接收密钥材料时，TLS 密钥都将追加到指定的文件中，如果它不存在，则创建该文件。键盘日志文件仅用于调试目的。

​SSLKEYLOGFILE​支持需要Python 3.8和OpenSSL 1.1.1或更高版本。

例：

# test_script.py
import httpx

with httpx.AsyncClient() as client:
    r = client.get("https://google.com")

SSL_CERT_FILE

有效值：文件名

如果设置了此环境变量，则 HTTPX 将从指定文件而不是默认位置加载 CA 证书。

例：

SSL_CERT_FILE=/path/to/ca-certs/ca-bundle.crt python -c "import httpx; httpx.get('https://example.com')"

SSL_CERT_DIR

有效值：遵循 OpenSSL 特定布局的目录。

如果设置了此环境变量，并且目录遵循OpenSSL特定布局（即您运行了​c_rehash​），则HTTPX将从此目录而不是默认位置加载CA证书。

例：

SSL_CERT_DIR=/path/to/ca-certs/ python -c "import httpx; httpx.get('https://example.com')"

NETRC

有效值：文件名

如果设置了此环境变量但未定义身份验证参数，则 HTTPX 会将存储在 .netrc 文件中的身份验证信息添加到请求的标头中。如果您也没有提供 NETRC 环境，HTTPX 将使用默认文件。（~/.netrc， ~/_netrc）

例：

NETRC=/path/to/netrcfile/.my_netrc python -c "import httpx; httpx.get('https://example.com')"

代理

下面记录的环境变量被各种 HTTP 工具用作约定，包括：

• cURL
• requests

有关在 HTTPX 中使用代理的详细信息，请参阅 HTTP 代理。

HTTP_PROXY, ,HTTPS_PROXYALL_PROXY

有效值：代理的 URL

​HTTP_PROXY​、​HTTPS_PROXY​、​ALL_PROXY​分别设置要用于​http ​、​https​ 或所有请求的代理。

export HTTP_PROXY=http://my-external-proxy.com:1234

# This request will be sent through the proxy
python -c "import httpx; httpx.get('http://example.com')"

# This request will be sent directly, as we set `trust_env=False`
python -c "import httpx; httpx.get('http://example.com', trust_env=False)"

NO_PROXY

有效值：以逗号分隔的主机名/url 列表

NO_PROXY禁用特定网址的代理

export HTTP_PROXY=http://my-external-proxy.com:1234
export NO_PROXY=http://127.0.0.1,python-httpx.org

# As in the previous example, this request will be sent through the proxy
python -c "import httpx; httpx.get('http://example.com')"

# These requests will be sent directly, bypassing the proxy
python -c "import httpx; httpx.get('http://127.0.0.1:5000/my-api')"
python -c "import httpx; httpx.get('https://www.python-httpx.org')"