Merge pull request #24845 from lujun9972/add-MjAyMjAzMDIgSG93IHRvIHVzZSBodHRweCwgYSB3ZWIgY2xpZW50IGZvciBQeXRob24ubWQK

自动选题[tech]: 20220302 How to use httpx, a web client for Python

sources/tech/20220302 How to use httpx, a web client for Python.md

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+[#]: subject: "How to use httpx, a web client for Python"
+[#]: via: "https://opensource.com/article/22/3/python-httpx"
+[#]: author: "Moshe Zadka https://opensource.com/users/moshez"
+[#]: collector: "lujun9972"
+[#]: translator: " "
+[#]: reviewer: " "
+[#]: publisher: " "
+[#]: url: " "
+
+How to use httpx, a web client for Python
+======
+The httpx package for Python is an excellent and flexible module for
+interacting with HTTP.
+![Digital creative of a browser on the internet][1]
+
+The `httpx` package for Python is a sophisticated web client. Once you install it, you can use it to get data from websites. As usual, the easiest way to install it is with the `pip` utility:
+
+
+```
+`$ python -m pip install httpx --user`
+```
+
+To use it, import it into a Python script, and then use the `.get` function to fetch data from a web address:
+
+
+```
+
+
+import httpx
+result = httpx.get("<https://httpbin.org/get?hello=world>")
+result.json()["args"]
+
+```
+
+Here's the output from that simple script:
+
+
+```
+`    {'hello': 'world'}`
+```
+
+### HTTP response
+
+By default, `httpx` will not raise errors on a non-200 status. 
+
+Try this code:
+
+
+```
+
+
+result = httpx.get("<https://httpbin.org/status/404>")
+result
+
+```
+
+The result:
+
+
+```
+`    <Response [404 NOT FOUND]>`
+```
+
+It's possible to raise a response explicitly. Add this exception handler:
+
+
+```
+
+
+try:
+    result.raise_for_status()
+except Exception as exc:
+    print("woops", exc)
+
+```
+
+Here's the result:
+
+
+```
+
+
+    woops Client error '404 NOT FOUND' for url '<https://httpbin.org/status/404>'
+    For more information check: <https://httpstatuses.com/404>
+
+```
+
+### Custom client
+
+It is worthwhile to use a custom client for anything but the simplest script. Aside from nice performance improvements, such as connection pooling, this is a good place to configure the client.
+
+For example, you can set a custom base URL:
+
+
+```
+
+
+client = httpx.Client(base_url="<https://httpbin.org>")
+result = client.get("/get?source=custom-client")
+result.json()["args"]
+
+```
+
+Sample output:
+
+
+```
+`    {'source': 'custom-client'}`
+```
+
+This is useful for a typical scenario where you use the client to talk to a specific server. For example, using both `base_url` and `auth`, you can build a nice abstraction for an authenticated client:
+
+
+```
+
+
+client = httpx.Client(
+    base_url="<https://httpbin.org>",
+    auth=("good_person", "secret_password"),
+)
+result = client.get("/basic-auth/good_person/secret_password")
+result.json()
+
+```
+
+Output:
+
+
+```
+`    {'authenticated': True, 'user': 'good_person'}`
+```
+
+One of the nicer things you can use this for is constructing the client at a top-level "main" function and then passing it around. This lets other functions use the client and lets them get unit-tested with a client connected to a local WSGI app.
+
+
+```
+
+
+def get_user_name(client):
+    result = client.get("/basic-auth/good_person/secret_password")
+    return result.json()["user"]
+
+get_user_name(client)
+    'good_person'
+
+def application(environ, start_response):
+    start_response('200 OK', [('Content-Type', 'application/json')])
+    return [b'{"user": "pretty_good_person"}']
+fake_client = httpx.Client(app=application, base_url="<https://fake-server>")
+get_user_name(fake_client)
+
+```
+
+Output:
+
+
+```
+`    'pretty_good_person'`
+```
+
+### Try httpx
+
+Visit [python-httpx.org][2] for more information, documentation, and tutorials. I've found it to be an excellent and flexible module for interacting with HTTP. Give it a try and see what it can do for you.
+
+--------------------------------------------------------------------------------
+
+via: https://opensource.com/article/22/3/python-httpx
+
+作者：[Moshe Zadka][a]
+选题：[lujun9972][b]
+译者：[译者ID](https://github.com/译者ID)
+校对：[校对者ID](https://github.com/校对者ID)
+
+本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
+
+[a]: https://opensource.com/users/moshez
+[b]: https://github.com/lujun9972
+[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/browser_web_internet_website.png?itok=g5B_Bw62 (Digital creative of a browser on the internet)
+[2]: https://www.python-httpx.org/