Getting error while sending C2D message via Service Client. (Error: failed to send message: protocol error: received flow without next-incoming-id after session established)

[devak8]

Below is the code used to C2D (Service client Sender)

`package iothub

import (
"context"
"fmt"
"log"

"github.com/amenzhinsky/iothub/iotservice"

)

// SendMessage sends a message to the specified IoT Hub device.
func SendMessage(iotHubConnectionString, deviceID, messageContent string) {
// Create a new IoT Hub service client using the connection string
client, err := iotservice.NewFromConnectionString(iotHubConnectionString)
if err != nil {
log.Fatalf("failed to create IoT Hub service client: %v", err)
}

// Prepare the message to be sent to the device
// message := &iotservice.Message{
// 	Data: []byte(messageContent),
// }

data := []byte(messageContent)

// Send the cloud-to-device message to the specified device

if err := client.SendEvent(context.Background(), deviceID, data); err != nil {
	log.Fatalf("failed to send message: %v", err)
}

fmt.Println("Message sent to device successfully.")

}
`

[devak8]

We are using below modules package:

github.com/amenzhinsky/iothub v0.9.2-0.20230710081242-d4c494d2c439

[pedrolemos4]

It might be the Transport you are using, your device might be blocking it, try to change it

[PremSahooESL]

What do you mean by transport?
Would you please elaborate it more?
We are able to send the data from Java Service Client for the same device, but not from this Go Package.

[pedrolemos4]

Try setting your client like this client, err := iotservice.NewFromConnectionString(iotHubConnectionString, iotservice.WithHTTPClient(http.DefaultClient))
With this you are setting a different way to communicate with iothub. I'm not sure but that might be your issue. If this does not work, check in the library what other method are .With...() and try with those.

[PremSahooESL]

does not it support 'amqps' protocol instead of http?

[devak8]

client, err := iotservice.NewFromConnectionString(iotHubConnectionString, iotservice.WithHTTPClient(http.DefaultClient))

Above code throws same previously mentioned error, even we tried with other 2 (WithLogger , WithTLSConfig)

do you have any working examples?

[pedrolemos4]

Show the error

[devak8]

2024/09/05 16:43:31 failed to send message: protocol error: received flow without next-incoming-id after session established

[pedrolemos4]

I think your issue is because you are using iotservice to send a message. This should be turned flow
1- Create a Device in Iothub using iotservice lib
2- Create a client for the device using iotclient lib
3- Connect and send a event using the device's client

[PremSahooESL]

1. IotHub device is already created.
2. Now we need to send data from C2D (Cloud to Device) for the specific device.
3. So we must use Service client library with IotHub service connection string, device ID and payload.
4. This is the Service Client's responsibility to send message to IotHub  for the specific Device.

[PremSahooESL]

If IoTHub Device wants to send message (D2C), then it must use Device Client.
Our case is just opposite of it.

[PremSahooESL]

Could you please provide working sample code of Service Client sender, if you have any?

[pedrolemos4]

You're right. I read wrong
First things first, you can send a message from the iothub to the device?

[PremSahooESL]

yes, true.

[PremSahooESL]

From Azure portal we can directly send a C2D message for specific device. And the device receives the data without any issue.
But we can not send the same data by using GoLang Service Client lib.

But it works from Java Service Client

[PremSahooESL]

is there any thing wrong with the amqp protcol version?

[devak8]

Hey , if you have any sample code for that specific library for the C2D communication , then please provide , or any pseudo code ?

[devak8]

Hi please give some updates about the above thread??

[devak8]

@amenzhinsky please have a look into the above issue in thread.

[devak8]

Hi @pedrolemos4 please do some comment on the above thread , it's getting blocker for me
Thanks in advance !

[devak8]

Hi Folks !
Is there any update on the above issue thread , please give your insight on this.
is there any issue with the library : github.com/amenzhinsky/iothub/iotservice
message is not getting sent (C2D communication)

[devak8]

is there any issue with AMQP
with this library i am using : github.com/amenzhinsky/iothub/iotservice

getting this error only : received flow without next-incoming-id after session established

[devak8]

Or is there some setting that needs to be configured in the IoT Hub to prevent this from happening? : protocol error: received flow without next-incoming-id after session established

I would really appreciate if someone is able to jump on this one.

[PremSahooESL]

var fixedIncomId uint32 = 12345
var nIncomIdPtr *uint32 = &fixedIncomId

case *frames.PerformFlow:
				body.NextIncomingID = nIncomIdPtr

				if body.NextIncomingID == nil {
					// This is a protocol error:
					//       "[...] MUST be set if the peer has received
					//        the begin frame for the session"
					closeWithError(&Error{
						Condition:   ErrCondNotAllowed,
						Description: "next-incoming-id not set after session established",
					}, errors.New("protocol error: received flow without next-incoming-id after session established"))
					continue
				}

[PremSahooESL]

in Azure/go-amqp/session.go file

body.NextIncomingID == nil

above condition expects some uint32 type NextIncomingID
Generally when iotservice sends message, it is always nil, so we were getting the error 'protocol error: received flow without next-incoming-id after session established'

I just made it to a hardcoded value '12345'. Now we got rid of this error.

[PremSahooESL]

Do not know though, how to pass body.NextIncomingI value as non-nil while sending the message (C2D)