chat (0)

The chat message is used to send a standard, plain-text message to a contact or a group. It is the most common message type within the Spixi application layer. The payload contains the UTF-8 encoded text content.

This message is sent within a SpixiMessage envelope, which specifies the chat type and the destination channel. The outer StreamMessage provides the secure, encrypted transport across the S2 network.

Core Data Types

• string: A standard UTF-8 encoded string. Per global serialization rules, its length is prefixed as a 7-bit encoded integer when serialized by the SpixiMessage layer, but the payload here is considered the raw string content.

Payload Structure

The entire payload of a chat message consists of a single field containing the message text.

Field	Data Type	Min	Max	Description
messageText	string	1	~50KB	The UTF-8 encoded content of the chat message. The maximum size is constrained by the underlying StreamMessage limits.

Behavioral Notes

• Sending: When a user sends a chat message, the client application constructs this message, places it within a SpixiMessage, and then wraps it in a StreamMessage of type data. The StreamMessage is then encrypted for the recipient and sent into the S2 network.
• Receiving: Upon receiving a SpixiMessage of type chat, the recipient's client must decode the data payload as a UTF-8 string to display it to the user.
• Confirmation: The StreamMessage containing a chat payload sets the requireRcvConfirmation flag. The receiving node is obligated to respond with a msgReceived message to confirm delivery.
• Context: The channel field in the SpixiMessage envelope indicates which conversation thread (e.g., a specific group chat channel) the message belongs to. For direct messages, this is typically channel 0.