Middleware with Asynchronous Call Causes POST Endpoint to Stall When Calling res.get_json()

[ArthoPacini]

When using a middleware that performs an asynchronous operation, the endpoint /api/v1/my_resource_problem stalls and never responds. In contrast, the endpoints /api/v1/my_resource and /api/v1/my_resource_functional work as expected.

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Steps to Reproduce

1. Run the following code:

   from socketify import App, AppOptions, OpCode, CompressOptions, middleware, AppListenOptions
   import faulthandler
   import aiosqlite
   faulthandler.enable()
   
   class SimpleDatabase:
       def __init__(self, db_path: str = ":memory:"):
           self.db_path = db_path
   
       async def get_data(self):
           async with aiosqlite.connect(self.db_path) as db:
               async with db.execute("SELECT RANDOM()") as cursor:
                   row = await cursor.fetchone()
                   return row[0] if row else None
   
   simple_database = SimpleDatabase()
   
   async def problem_middleware(res, req, data=None):
       my_random_number = await simple_database.get_data()
       return {"hello":"world"}
   
   async def functional_middleware(res, req, data=None):
       return {"hello":"world"}
   
   async def post_data(res, req, data=None):
       data = await res.get_json()
       print(data)
       res.cork_end({"success": True})
       
   
   
   def make_app(app):   
       app.post("/api/v1/my_resource", post_data)
       app.post("/api/v1/my_resource_problem", middleware(problem_middleware, post_data))
       app.post("/api/v1/my_resource_functional", middleware(functional_middleware, post_data))
   
   from typing import Dict, Any, Callable, List, Optional, Union, Literal
   
   app = App()
   make_app(app)
   
   app.listen(AppListenOptions(port=5555, host="0.0.0.0"), lambda config: print(f"Listening on port http://{config.host}:%d now\n" % (config.port)))
   app.run()

2. Send a POST request with valid JSON data to the following endpoints:

   • /api/v1/my_resource
   • /api/v1/my_resource_functional
   • /api/v1/my_resource_problem

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Expected Behavior

All endpoints should respond with (and print the posted data in the stdout):

{
  "success": True
}

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Actual Behavior

• /api/v1/my_resource and /api/v1/my_resource_functional respond correctly.
• /api/v1/my_resource_problem stalls and never replies.

---

Additional Information

It appears that await res.get_json() enters an infinite loop when a previous middleware performs an asynchronous call, such as my_random_number = await simple_database.get_data().

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Environment

• socketify Version: 0.0.31

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Note: same behavior happens on data = await res.get_data().

Actually the problem seems to happen inside the .get_data() (it is called from the .get_json().

[ArthoPacini]

also, it seems that a call to res.get_data() or res.get_json() works, just before an asynchronous call.

When posting on the problematic endpoint, it will successfully print a valid json once, and then will hang, this modified middleware can show this behavior:

async def problem_middleware(res, req, data=None):
    data = await res.get_json() # Will not hang
    print(data) # Will print normally
    my_random_number = await simple_database.get_data()
    data = await res.get_json() # Will Hang forever
    print(data)
    return {"hello":"world"}

[ArthoPacini]

The workaround is the get all data beforehand and pass it around middleware calls, before any asynchronous call