update to latest trio, use contextvars for logging

2026-07-10 10:24:25 +00:00 · 2019-02-12 00:32:47 +00:00
parent 23a8055a2e
commit 7942e83d1d
4 changed files with 202 additions and 87 deletions
--- a/README.rst
+++ b/README.rst
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+trio_http_proxy.py
+==================
+
+Simple HTTP CONNECT proxy implemented with
+`Trio <https://trio.readthedocs.io>`__.
+
+Tested with Python 3.7 and Trio 0.11.0
+(but other versions probably work too).
+
+
+Why
+---
+
+- An HTTP CONNECT proxy is one of the simplest
+  async I/O things you can build
+  that does something real.
+  Namely, you can load HTTPS sites
+  (including streaming YouTube and Netflix)
+  through it.
+
+- If you're trying to access content that's restricted by an IP-based geofence,
+  you could run this from a machine inside the geofence to get access!
+
+  Note: Please consult the relevant terms and conditions first
+  to make sure you wouldn't be breaking the rules.
+  😇
+
+  Also note: Many popular streaming services
+  blacklist IPs of major cloud hosting providers
+  to thwart unauthorized geofence hopping.
+  So you'd need to run this from
+  `some other hosting provider <http://lowendbox.com>`__.
+
+- I was sold on Trio *before* I saw
+  `@njsmith <https://github.com/njsmith>`__
+  `live code happy eyeballs in 40 lines of Python
+  <https://www.youtube.com/watch?v=i-R704I8ySE>`__.
+  🙀
+
+  If you haven't yet read his post,
+  `Notes on structured concurrency, or: Go statement considered harmful
+  <https://vorpus.org/blog/notes-on-structured-concurrency-or-go-statement-considered-harmful/>`__
+  definitely check it out.
+
+
+Instructions
+------------
+
+#. Install Trio if you haven't already.
+
+   .. code-block::
+
+      pip install trio
+
+#. In one shell session, run this script to start the proxy on port 8080:
+
+   .. code-block::
+
+      ./trio_http_proxy.py
+      * Starting HTTP proxy on port 8080...
+
+   (You can set the PORT env var to use a different port if you prefer.)
+
+#. In another session, make an HTTPS request through the proxy, e.g.
+
+   .. code-block::
+
+      curl -x http://127.0.0.1:8080 https://canhazip.com
+
+   You should get the response you were expecting from the destination server,
+   and should see output from the proxy in the first shell session
+   about the forwarded data, e.g.
+
+   .. code-block::
+
+      [conn1] Reading...
+      [conn1] Got CONNECT request for canhazip.com, connecting...
+      [conn1 <> canhazip.com] Connected to canhazip.com, sending 200 response...
+      [conn1 <> canhazip.com] Sent "200 Connection established" to client, tunnel established.
+      [conn1 -> canhazip.com] Forwarded 196 bytes
+      [conn1 <- canhazip.com] Forwarded 2954 bytes
+      ...
+
+#. You can even configure your OS or browser to use the proxy,
+   and then try visiting some HTTPS websites as you would normally.
+   It works! 💪
+
+   HTTP sites won't work because the proxy only handles HTTP CONNECT requests.
+   But HTTP is weak sauce anyways. 🤓
+
+   *A YouTube video streaming through the proxy:*
+
+   .. image:: https://user-images.githubusercontent.com/64992/38785817-c03acd0a-414d-11e8-8f4a-2c5aa27e79e6.png
+      :alt: screenshot of a YouTube video streaming through the proxy
+
+   *Changing system proxy settings on macOS:*
+
+   .. image:: https://user-images.githubusercontent.com/64992/38785931-b657d804-414e-11e8-8cfa-e05a11364f7d.png
+      :alt: screenshot of changing system proxy settings on macOS
+
+#. When you're done, just hit Ctrl+C to kill the server.
+   Don't forget to restore any proxy settings you changed
+   to how they were set before.
+
+
+For a one-liner test that only requires one shell session, run:
+
+.. code-block::
+
+   ./trio_http_proxy.py & sleep 1; curl -x http://127.0.0.1:8080 https://canhazip.com ; kill %1