ListServiceConversationMessage(): "could not retrieve payload from response"

[zs-codex]

Issue Summary

The ConversationsV1 REST API for ListServiceConversationMessage() returns the following error if no messages exist in the conversation:

| could not retrieve payload from response

However, we would expect the returned result to be either

1. An empty slice instead with no error
2. A Twilio-defined error API code from the list.

Steps to Reproduce

1. Query any conversation that contains no messages

Code Snippet

messages, err := client.ConversationsV1.ListServiceConversationMessage(serviceSid, conversationUniqueName, &conversations.ListServiceConversationMessageParams{})

Exception/Log

# paste exception/log here

Technical details:

• twilio-go version: v0.14.1
• go version: go1.16 darwin/amd64

[shwetha-manvinkurke]

Makes sense. This issue has been added to our internal backlog to be prioritized. Pull requests and +1s on the issue summary will help it move up the backlog.

Internal tracking

[mwajeeh]

It is a generic issue in paging library which throws error could not retrieve payload from response if there is no result. I am getting it on ListPhoneNumber() api.

[shwetha-manvinkurke]

@mwajeeh Yup we are aware of it. It's in the backlog being prioritized.

[sarahcstringer]

+1, also seeing this on PlayerStreamer and MediaProcessor list resources.

[saurori]

I believe I tracked down this problem. It has to do with response types having omitempty.

An example of this can be seen on the ListCallResponse. If omitempty is removed, the Calls struct will have an empty slice value and will be present when the response is marshaled in toMap. The page_util.go code will detect the empty slice and append it to the data slice, and not cause an error.

If you look at an empty json response to the Calls endpoint, the "calls": [] empty array indicates the field has empty data and not null data. Therefore I think that omitempty is incorrect and the response field should not be nullable (in the OAI spec?).

{
    "first_page_uri": "/2010-04-01/Accounts/ACxx/Calls.json?EndTime%3C=2021-11-27T10%3A22%3A51+00%3A00&StartTime%3E=2021-11-27T16%3A22%3A51+00%3A00&PageSize=20&Page=0",
    "end": 0,
    "calls": [],
    "previous_page_uri": null,
    "uri": "/2010-04-01/Accounts/ACxx/Calls.json?EndTime%3C=2021-11-27T10%3A22%3A51+00%3A00&StartTime%3E=2021-11-27T16%3A22%3A51+00%3A00&PageSize=20&Page=0",
    "page_size": 20,
    "start": 0,
    "next_page_uri": null,
    "page": 0
}

[childish-sambino]

Fixed by https://github.com/twilio/twilio-go/pull/148