How do I warm up the cache properly?

[shizzard]

TL;DR: I cannot find a proper way to get a message author display name. Permissions are all, bot permissions parameters are all set to be privileged.

The msg.member(&ctx).await is never Ok(...) (actually, it is always an Err() with reason The required item is missing from the cache.).
I know that discord only sends partial guild information when client is connected, that's why there is a Request Guild Members event on a gateway. However, it seems that this event is never sent, and the members list is not populated.
For me it seems that I'm doing something wrong and missing some crucial step here.

[GnomedDev]

Message::member only returns MissingItem if the Message::guild_id is None, does that help you?

[shizzard]

Uh, yes, it seems correct, for some reason the guild_id in the message is None.
Short introduction: I'm building a simple command that collects last N messages from the channel and reports a summary with a call to OpenAI API.
The message list I'm getting in the prototype is the following:

ctx.http.get_messages(msg.channel_id, Some(MessagePagination::Before(msg.id)), Some(100)).await?;

These messages are in the guild channel, but the guild_id field is None.
Is that a flaw of discord API?..

NB: For some reason the msg.message_reference.guild_id field is Some(...), but the msg.referenced_message.guild_id is None.
JFYI, a stripped data:

    Message {
        id: MessageId(...),
        channel_id: ChannelId(...),
        author: User {...},
        content: "...",
        ...
        message_reference: Some(
            MessageReference {
                message_id: Some(MessageId(...),),
                channel_id: ChannelId(...),
                guild_id: Some(GuildId(...),),
                fail_if_not_exists: None,
            },
        ),
        flags: Some(...),
        referenced_message: Some(
            Message {
                id: MessageId(...),
                channel_id: ChannelId(...),
                author: User {
                    ...
                    member: None,
                },
                ...
                guild_id: None,
                member: None,
            },
        ),
        ...
        guild_id: None,
        member: None,
    }

[jamesbt365]

The guild_id in message in none because it was not received over the gateway (the MessageCreate event), the docs on the Message struct outlines this.

[shizzard]

Yes, that's right.
The workaround for anyone facing the same problem in the future: use ctx.http.get_member method and pass the original message (from the MessageCreate event) msg.guild_id.expect(...) as the first parameter.
Thank you!