From 61cd95d883bbcbe1ca0dd6deb3829b29f29cfeff Mon Sep 17 00:00:00 2001
From: Tyler Goodlet <jgbt@protonmail.com>
Date: Wed, 18 Sep 2024 22:47:59 -0400
Subject: [PATCH] Add a super naive multi-host-capable web-req proxier for
 @jc211

---
 examples/multihost/client.py | 50 ++++++++++++++++++++++++
 examples/multihost/server.py | 75 ++++++++++++++++++++++++++++++++++++
 2 files changed, 125 insertions(+)
 create mode 100644 examples/multihost/client.py
 create mode 100644 examples/multihost/server.py

diff --git a/examples/multihost/client.py b/examples/multihost/client.py
new file mode 100644
index 0000000..888b100
--- /dev/null
+++ b/examples/multihost/client.py
@@ -0,0 +1,50 @@
+import tractor
+import trio
+
+
+log = tractor.log.get_console_log(
+    _root_name='my_app',
+    name='client',
+)
+
+
+async def client_main():
+
+    # enable console logging for our custom app's logger
+    tractor.log.get_console_log(
+        level='info',
+        _root_name='my_app',
+        name='client',
+    )
+
+    # presuming you can get a ref to the target server RPC-ctx func
+    from server import proxy_request
+
+    async with (
+        tractor.open_root_actor(
+            name='web_requester',
+            registry_addrs=[('127.0.0.1', 1616)],
+            enable_modules=[],  # since this isn't a service actor
+        ),
+
+        # use discovery api to find the server actor on your net
+        # (NOTE, in which case the below registry addr would have to
+        # be the public IP of that host!)
+        tractor.find_actor(
+            name='web_proxier',
+            registry_addrs=[('127.0.0.1', 1616)],
+        ) as portal,
+
+        # open an RPC context with the remote actor, thus spawning
+        # a new task implemented as the function defined in the
+        # server code.
+        portal.open_context(
+            proxy_request,
+            address='https://github.com',
+        ) as (ctx, first),
+    ):
+        resp: dict = await ctx.result()
+        print(resp)
+
+
+trio.run(client_main)
diff --git a/examples/multihost/server.py b/examples/multihost/server.py
new file mode 100644
index 0000000..8f43b58
--- /dev/null
+++ b/examples/multihost/server.py
@@ -0,0 +1,75 @@
+import httpx
+import tractor
+import trio
+
+log = tractor.log.get_console_log(
+    _root_name='my_app',
+    name='server_thingy',
+)
+
+
+@tractor.context
+async def proxy_request(
+    ctx: tractor.Context,
+    address: str,
+):
+    log.info(
+        'Rxed client request\n'
+        f'{address}\n'
+    )
+    async with httpx.AsyncClient() as client:
+        await ctx.started()  # signal the remote task has started its client
+        log.info(
+            'Opened `httpx` client..'
+        )
+
+        resp: httpx.Response = await client.get(address)  # do the proxied request, get response.
+        log.info(
+            'Got response..\n'
+            f'{resp}\n'
+        )
+
+        # only breaking this up to clarify that you didn't have to only return a single result you could have opened
+        # a long lived stream to avoid task spawning overhead in this service actor.. but more on that later..
+        #
+        # NOTEs, cast to `str` here since we can't serialize the
+        # response type for the wire directly, at least no without
+        # a custom `msgspec.Decoder`!!
+        return str(resp)
+        #
+        # ^TODO, various typed msging options:
+        # -[ ] try returning just the `resp` verbatim => should raise
+        #    an MTE
+        # -[ ] try defining a custom `Response` msg to proxy the orig
+        #     types fields and/or a decoder to serialize it?
+
+
+async def main():
+
+    # enable console logging for our custom app's logger
+    tractor.log.get_console_log(
+        level='info',
+        _root_name='my_app',
+        name='server_thingy',
+    )
+
+    # since run as a script this will likely be `__main__`
+    # so instead we want to just use our module name..
+    this_mod: str = 'server'
+    async with tractor.open_root_actor(
+        name='web_proxier',
+        registry_addrs=[('127.0.0.1', 1616)],
+        enable_modules=[this_mod],
+        loglevel='info',
+    ):
+        # just block waiting for a peer actor to connect and open an RPC context using the above
+        # proxy endpoint.
+        log.info(
+            'proxy server up bby!\n'
+            'waiting to serve some requests..\n'
+        )
+        await trio.sleep_forever()
+
+
+if __name__ == '__main__':
+    trio.run(main)