array of maps in json about grpc-gateway

[yugui]

I guess both proto3 and grpc-gateway are working fine, but let me confirm.

IIUC, you defined a service which takes an Alerts message as a request, and tried to pass exactly [{"2":"3"}] as an HTTP request body.
Your generated gateway rejected this request because it expects a JSON object as a request body but received an array of JSON objects.

In this case, an example of the request format which your gateway expects is something like

{
    "alert": [
        {
            "m": {
                "1": "2",
                "3": "4"
            }
        },
        {
            "m": {
                "5": "6"
            }
        }
    ]
}

FYI,

• the gateway accepted {"1": "2"} because JSON unmarshaller just ignores unknown keys.
• proto3 does not allow repeated map fields but allows repeated message fields which contain maps.

[miekg]

Thanks for your reply. And, yes exactly what you describe. I will work around it.