Listen to gRPC UNARY_STREAM Connection

[gandhishripala]

I want to make connection to gRPC UNARY_STREAM and then list to response of Stream,

Example scenario:

1. Open connection to greeter_service.SayHelloGroup
2. Call other methods
3. Read response from greeter_service.SayHelloGroup
4. Repeat steps from 2-3

    client = AsyncClient(
        "localhost:50051", descriptor_pool=descriptor_pool.DescriptorPool()
    )
    greeter_service = await client.service("helloworld.Greeter")
    async with greeter_service.SayHelloGroup({"name": "sinsky"}) as greeter_connection:
        response = await anext(greeter_connection)
        assert response

Can someone guide me on how this can be achieved?

[aidandj]

Does this work?

client = AsyncClient(
    "localhost:50051", descriptor_pool=descriptor_pool.DescriptorPool()
)
greeter_service = await client.service("helloworld.Greeter")
async for response in greeter_service.SayHelloGroup({"name": "sinsky"}):
    assert response

[gandhishripala]

Sorry for delayed response, this worked. Thank you, I missed await in for statement.

[gandhishripala]

Another query, how do we close this connection? I tried with break in async for loop, it throws message (don't have exact message can share that) that thread is waiting for response and connection is closed.

[gandhishripala]

Exact Message is: Task was destroyed but it is pending!

[ViridianForge]

Apologies for the long delay on noticing the discussion @gandhishripala .
I believe that the client will close on its own at the end of your routine, provided you have waited for, and received, all responses expected.

If you're in a situation where the streaming side of the connection will stream until hung up upon, you may want to explore setting a client max connection time in the client config, or setting some other criterion your loop checks upon which where you force a closure of the channel or client.

As for Task was destroyed but it is pending - I believe that error means that the coroutine didn't have time to finish all its tasks before the loop was broken.

[gandhishripala]

Thank you for your inputs, @ViridianForge . Also Thank you @artificial-aidan .