Messages

Message models are split into two groups: inbound gateway payloads and outbound parameter structs. The current implementation focuses on those two paths: events deserialize into usable payloads, and handlers can reply through the framework API.

Inbound Messages

Guild channel @bot messages use Message, delivered to EventHandler::message_create. Direct-message events also use Message, delivered to direct_message_create; fields such as direct_message and src_guild_id identify the DM scene.

Group and C2C messages have their own models:

• GroupMessage maps to GROUP_AT_MESSAGE_CREATE; the key routing field is group_openid.
• C2CMessage maps to C2C_MESSAGE_CREATE; the key routing field usually comes from author.user_openid.

These event models retain platform-provided message id, content, attachments, mentions, timestamp, references, and internal event_id. Message id, content, author, routing id, and timestamp are required fields on normal message events; group/C2C messages also carry the required open-message message_type. Optional protocol fields stay optional.

Attachments use MessageAttachment. When an attachment appears, the filename, content type, size, and URL are plain fields. id stays optional because open-message attachment payloads may omit it, while width and height default to 0 for non-image or payloads that do not include dimensions.

let message = session.message();
if !message.author.bot && message.content.trim() == "/ping" {
    session.reply("pong").await?;
}

Sending Messages

Outbound sending uses four parameter types:

Parameter type	Use
MessageParams	Guild channel messages
DirectMessageParams	Direct-message session messages
GroupMessageParams	Group messages
C2CMessageParams	C2C messages

Use session helpers inside reply-capable handlers:

session.reply("pong").await?;
session.send_markdown_message("# hello").await?;
session.send_embed_message(embed).await?;

For direct BotApi calls or custom fields, use params constructors:

let params = MessageParams::new_text("pong").with_reply(message_id);
session.send_message(params).await?;

The rich constructors are new_markdown, new_ark, new_embed, new_keyboard, and, for group/C2C messages, new_media. Set fields directly only when you need a protocol field not covered by those constructors:

• embed for embed messages.
• ark for ark templates.
• markdown for markdown templates or markdown content.
• keyboard for button keyboards.
• media for media returned by group/C2C file upload.

DirectMessage

DirectMessage is the session DTO returned after creating a direct-message session. The send flow is:

1. Create a session request with DirectMessageToCreate::new(source_guild_id, recipient_id).
2. Call create_direct_message to receive DirectMessage.
3. Use the returned guild_id with send_direct_message.

let dm = DirectMessageToCreate::new(&guild_id, &user_id);
let dm_session = session.create_direct_message(&dm).await?;

let params = DirectMessageParams::new_text("hello");
session.send_direct_message(&dm_session.guild_id, params).await?;

Open Message Types

Group and C2C messages still serialize to the platform's open-message type codes, but normal user code should use session helpers or params constructors instead of setting the numeric value by hand. Guild channel and direct-message params use MessageCreateType internally.

See Also

• BotApi
• Users and Members
• Other types