Enum Frame 

pub enum Frame {
    Connect {
        flags: u8,
        min_version: ProtocolVersion,
        max_version: ProtocolVersion,
        auth_token: Vec<u8>,
    },
    ConnectAck {
        flags: u8,
        selected_version: ProtocolVersion,
        capabilities: u32,
    },
    ConnectError {
        flags: u8,
        reason_code: u16,
        message: Option<String>,
    },
    Disconnect {
        flags: u8,
    },
    DisconnectReason {
        flags: u8,
        reason: DisconnectReason,
    },
    Subscribe {
        flags: u8,
        stream_id: u32,
        channel: String,
        accepted_schemas: Vec<SchemaId>,
        max_in_flight: u32,
    },
    SubscribeAck {
        flags: u8,
        stream_id: u32,
        subscription_id: u64,
        selected_schema: SchemaId,
    },
    SubscribeError {
        flags: u8,
        stream_id: u32,
        reason_code: u16,
        message: Option<String>,
    },
    Unsubscribe {
        flags: u8,
        stream_id: u32,
        subscription_id: u64,
    },
    Publish {
        flags: u8,
        stream_id: u32,
        channel: String,
        envelope: MessageEnvelope,
        idempotency_key: Option<String>,
    },
    PublishAck {
        flags: u8,
        stream_id: u32,
        message_id: u64,
        durable_position: Option<u64>,
    },
    PublishError {
        flags: u8,
        stream_id: u32,
        reason_code: u16,
        message: Option<String>,
    },
    ConversationOpen {
        flags: u8,
        stream_id: u32,
        conversation_id: u64,
        subject: String,
    },
    ConversationMessage {
        flags: u8,
        stream_id: u32,
        conversation_id: u64,
        envelope: MessageEnvelope,
    },
    ConversationClose {
        flags: u8,
        stream_id: u32,
        conversation_id: u64,
        reason_code: Option<u16>,
        message: Option<String>,
    },
    ConversationError {
        flags: u8,
        stream_id: u32,
        conversation_id: u64,
        reason_code: u16,
        message: Option<String>,
    },
    Accept {
        flags: u8,
        stream_id: u32,
        referenced_message_id: MessageId,
    },
    Defer {
        flags: u8,
        stream_id: u32,
        referenced_message_id: MessageId,
        reason: Option<String>,
    },
    Reject {
        flags: u8,
        stream_id: u32,
        referenced_message_id: MessageId,
        reason: Option<String>,
    },
    Ping {
        flags: u8,
    },
    Pong {
        flags: u8,
    },
    Push {
        flags: u8,
        stream_id: u32,
        correlation_id: u64,
        payload: Vec<u8>,
    },
    PushReply {
        flags: u8,
        stream_id: u32,
        correlation_id: u64,
        payload: Vec<u8>,
    },
    WorkerRegister {
        flags: u8,
        registration: WorkerRegistration,
    },
    WorkerRegisterAck {
        flags: u8,
        outcome: WorkerRegisterOutcome,
    },
    Deliver {
        flags: u8,
        stream_id: u32,
        delivery_seq: u64,
        envelope: MessageEnvelope,
        message: Option<DeliveredId>,
    },
    LinkOpen {
        flags: u8,
        stream_id: u32,
        offer: LinkOffer,
    },
    LinkOpenAck {
        flags: u8,
        stream_id: u32,
        outcome: LinkOpenOutcome,
    },
    LinkMessage {
        flags: u8,
        stream_id: u32,
        subject: String,
        sealed: Vec<u8>,
    },
    Unknown {
        type_id: u8,
        flags: u8,
        stream_id: u32,
        payload: Vec<u8>,
    },
}

A typed protocol frame body plus the header metadata required to encode it.

Variants

Connect

Connection request carrying a supported version range and opaque auth token.

Fields

flags: u8

min_version: ProtocolVersion

max_version: ProtocolVersion

auth_token: Vec<u8>

ConnectAck

Connection success carrying the negotiated protocol version and server capabilities.

Fields

flags: u8

selected_version: ProtocolVersion

capabilities: u32

ConnectError

Connection failure carrying a numeric reason and optional message.

Fields

flags: u8

reason_code: u16

message: Option<String>

Disconnect

Connection close notification with no payload.

Fields

flags: u8

DisconnectReason

Server close carrying a stable reason (ACCESS-005 R5): the body is a version byte (DISCONNECT_REASON_BODY_VERSION), the reason’s code and its name. Written only on a connection at REVOCATION_CLOSE_VERSION or later; the payload-free Frame::Disconnect is unchanged.

Fields

flags: u8

reason: DisconnectReason

Subscribe

Channel subscription request carrying a channel and accepted schema hashes.

Fields

flags: u8

stream_id: u32

channel: String

accepted_schemas: Vec<SchemaId>

max_in_flight: u32

SubscribeAck

Channel subscription success carrying a subscription id and selected schema.

Fields

flags: u8

stream_id: u32

subscription_id: u64

selected_schema: SchemaId

SubscribeError

Channel subscription failure carrying a numeric reason and optional message.

Fields

flags: u8

stream_id: u32

reason_code: u16

message: Option<String>

Unsubscribe

Channel unsubscription request carrying the subscription id.

Fields

flags: u8

stream_id: u32

subscription_id: u64

Publish

Publish request carrying a channel and typed message envelope.

idempotency_key is Some only when the PUBLISH_IDEMPOTENCY_KEY_FLAG flag bit is set; it is the dedup-on-delivery key the server feeds to its dedup cache. When None (and the flag clear) the frame is byte-identical on the wire to a pre-13-L1 publish.

Fields

flags: u8

stream_id: u32

channel: String

envelope: MessageEnvelope

idempotency_key: Option<String>

PublishAck

Publish success carrying the accepted message id.

durable_position is Some only when the ack answers for a stored row and the connection negotiated PUBLISH_ACK_POSITION_VERSION; the codec then sets PUBLISH_DURABLE_POSITION_FLAG and writes the position after message_id. When None the frame is byte-identical to the older ack.

Fields

flags: u8

stream_id: u32

message_id: u64

durable_position: Option<u64>

PublishError

Publish failure carrying a numeric reason and optional message.

Fields

flags: u8

stream_id: u32

reason_code: u16

message: Option<String>

ConversationOpen

Conversation open carrying a conversation id and subject.

Fields

flags: u8

stream_id: u32

conversation_id: u64

subject: String

ConversationMessage

Conversation message carrying a conversation id and typed message envelope.

Fields

flags: u8

stream_id: u32

conversation_id: u64

envelope: MessageEnvelope

ConversationClose

Conversation close carrying a conversation id and optional reason.

Fields

flags: u8

stream_id: u32

conversation_id: u64

reason_code: Option<u16>

message: Option<String>

ConversationError

Conversation failure carrying a conversation id, numeric reason, and optional message.

Fields

flags: u8

stream_id: u32

conversation_id: u64

reason_code: u16

message: Option<String>

Accept

Backpressure acceptance for a delivered message.

Fields

flags: u8

stream_id: u32

referenced_message_id: MessageId

Defer

Backpressure deferral for a buffered message.

Fields

flags: u8

stream_id: u32

referenced_message_id: MessageId

reason: Option<String>

Reject

Backpressure rejection for a shed message.

Fields

flags: u8

stream_id: u32

referenced_message_id: MessageId

reason: Option<String>

Ping

Connection keepalive ping.

Fields

flags: u8

Pong

Connection keepalive pong.

Fields

flags: u8

Push

Server-initiated push carrying a correlation id and an opaque payload.

A server writes this frame to a connected client over the client’s existing connection (server-to-client, the inverse of every other request frame). The correlation_id is the key the server uses to match the client’s later Frame::PushReply back to this push; the payload is opaque application bytes the server hands the client. This is an application-stream frame, so stream_id is non-zero like a publish or conversation message.

Fields

flags: u8

stream_id: u32

correlation_id: u64

payload: Vec<u8>

PushReply

Client-initiated correlated reply to a Frame::Push.

After handling a pushed frame the client writes this back on the same connection, echoing the push’s correlation_id so the server can match the reply to the originating push. The payload is the client’s opaque answer.

Fields

flags: u8

stream_id: u32

correlation_id: u64

payload: Vec<u8>

WorkerRegister

Worker self-registration over an established connection.

A worker sends this control frame (stream 0) after the connection handshake to announce its identity and routing dimensions. The server associates the registration with the connection’s process id and surfaces it to the application via the connection-notifier hook, then answers with a Frame::WorkerRegisterAck. node is optional locality and is encoded with a presence byte, never flattened to an empty string.

Fields

flags: u8

registration: WorkerRegistration

WorkerRegisterAck

Server acknowledgement of a Frame::WorkerRegister.

Carries the registration outcome: WorkerRegisterOutcome::Accepted when the server (and any configured notifier) accepted the worker, or WorkerRegisterOutcome::Rejected carrying a human-readable reason when it did not. The acknowledgement is synchronous so a worker never believes it is registered when the application rejected it.

Fields

flags: u8

outcome: WorkerRegisterOutcome

Deliver

Server-to-client delivery of a message on a subscription the client opened.

The server writes this frame on the subscription’s own stream_id (the non-zero application stream negotiated by the client’s Subscribe). It is the only server-originated delivery frame, and it is only ever sent on a subscription the client itself opened, so the forward-compatibility rules for unknown frames never surprise an old client with one. delivery_seq is a per-subscription monotonic counter starting at 1 — the anchor the future ack/resume (A1 v2 credit) protocol builds on. The envelope reuses the same MessageEnvelope serialization as publish and conversation frames.

message is Some only when the server knows the message’s id and boot and the connection negotiated DELIVER_MESSAGE_ID_VERSION; the codec then sets DELIVER_MESSAGE_ID_FLAG and writes the pair after the envelope. When None the frame is byte-identical to the older Deliver.

Fields

flags: u8

stream_id: u32

delivery_seq: u64

envelope: MessageEnvelope

message: Option<DeliveredId>

LinkOpen

A machine opening one end of a link on this application stream (ACCESS-002 R1). The server decides the open with Lys, live, for the grant the offered end names on the link, proves the offered machine key is the verified holder’s recorded key, and answers the handshake.

Fields

flags: u8

stream_id: u32

offer: LinkOffer

LinkOpenAck

The server’s answer to a Frame::LinkOpen on the same stream.

Fields

flags: u8

stream_id: u32

outcome: LinkOpenOutcome

LinkMessage

One message crossing an open link on its stream: the subject it is published on, and the message envelope sealed by the link’s transport. The receiving end decides the crossing from both machines’ passes before any effect.

Fields

flags: u8

stream_id: u32

subject: String

sealed: Vec<u8>

Unknown

Forward-compatible frame preserved after length-delimited skipping.

Fields

type_id: u8

flags: u8

stream_id: u32

payload: Vec<u8>

Implementations

impl Frame

pub fn new_ping(stream_id: u32) -> Result<Self, ProtocolError>

Construct a ping frame, enforcing the stream-0 control-frame invariant.

Errors

Returns ProtocolError::InvalidStream when stream_id is not zero.

pub fn new_publish( stream_id: u32, channel: impl Into<String>, envelope: MessageEnvelope, ) -> Result<Self, ProtocolError>

Construct a publish frame, enforcing the non-zero application-stream invariant.

Errors

Returns ProtocolError::InvalidStream when stream_id is zero.

pub fn new_publish_with_idempotency_key( stream_id: u32, channel: impl Into<String>, envelope: MessageEnvelope, idempotency_key: impl Into<String>, ) -> Result<Self, ProtocolError>

Construct a publish frame carrying an idempotency key for dedup-on-delivery.

The returned frame has PUBLISH_IDEMPOTENCY_KEY_FLAG set and serializes the trailing key field, so the server consults its dedup cache for this key.

Errors

Returns ProtocolError::InvalidStream when stream_id is zero.

pub fn new_push( stream_id: u32, correlation_id: u64, payload: Vec<u8>, ) -> Result<Self, ProtocolError>

Construct a server-to-client push frame, enforcing the non-zero application-stream invariant.

Errors

Returns ProtocolError::InvalidStream when stream_id is zero.

pub fn new_deliver( stream_id: u32, delivery_seq: u64, envelope: MessageEnvelope, ) -> Result<Self, ProtocolError>

Construct a server-to-client delivery frame on a subscription’s stream, enforcing the non-zero application-stream invariant.

Errors

Returns ProtocolError::InvalidStream when stream_id is zero.

pub fn new_push_reply( stream_id: u32, correlation_id: u64, payload: Vec<u8>, ) -> Result<Self, ProtocolError>

Construct a client-to-server push reply frame, echoing the correlation id of the originating push, and enforcing the non-zero application-stream invariant.

Errors

Returns ProtocolError::InvalidStream when stream_id is zero.

pub const fn frame_type(&self) -> FrameType

Return the frame type represented by this frame body.

pub const fn flags(&self) -> u8

Return the frame flags stored in the fixed header.

pub const fn wire_flags(&self) -> u8

Return the flags byte the codec writes into the fixed header.

This is Frame::flags except on a Frame::PublishAck, whose PUBLISH_DURABLE_POSITION_FLAG bit is set exactly when the ack carries a durable position, and a Frame::Deliver, whose DELIVER_MESSAGE_ID_FLAG bit is set exactly when it carries a DeliveredId, so the bit and the trailing field never disagree.

pub const fn stream_id(&self) -> u32

Return the stream id stored in the fixed header.

Trait Implementations

impl Clone for Frame

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Frame

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Frame

impl PartialEq for Frame

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Frame