Struct SystemMsg

Namespace

DatabentoDotNet.Dbn

Assembly

DatabentoDotNet.Dbn.dll

A non-error message from the Databento Live Subscription Gateway, also used for heartbeats.

public readonly struct SystemMsg : IRecord<SystemMsg>

Implements

IRecord<SystemMsg>

Inherited Members

ValueType.Equals(object)

ValueType.GetHashCode()

ValueType.ToString()

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Remarks

This is the DBN v2 layout, unchanged in v3, at 320 bytes. Version 1 is 80 bytes and carries only the message text — see SystemMsgV1. The record has no ts_recv, so its index timestamp is TsEvent.

Fields

Header

The common header.

public readonly RecordHeader Header

Field Value

RecordHeader

Msg

The message from the Databento gateway.

public readonly CStr303 Msg

Field Value

CStr303

RawCode

The raw wire byte behind Code. Not validated on decode — pass it to TryFromSystemCode(byte, out SystemCode) for a checked conversion.

public readonly byte RawCode

Field Value

byte

Properties

Code

The type of system message. Undefined wire bytes cast through to an unnamed value rather than throwing; see RawCode. Unset on a record upgraded from DBN v1 whose message matched none of the known texts.

public SystemCode Code { get; }

Property Value

SystemCode

IndexTs

The record's index timestamp: the one to sort by, and the one to key a symbol map with. Nanoseconds since the UNIX epoch.

public ulong IndexTs { get; }

Property Value

ulong

Remarks

This is usually ts_recv, not TsEvent. Fourteen of the twenty-one record structs carry a ts_recv and index on it; the rest have no ts_recv at all and fall back to the header's ts_event. Port of upstream's Record::raw_index_ts (record/traits.rs:52-54), whose default body is ts_event and which the #[dbn(index_ts)] field attribute overrides per struct (record.rs, compat.rs).

The distinction is not cosmetic: ts_event and ts_recv can fall on opposite sides of UTC midnight, so resolving a symbol by the wrong one silently returns the previous day's symbol, or nothing, with no error anywhere.

This is a raw timestamp and can be UndefTimestamp. Convert it with ToUtcDate(ulong) or TryToUtcDate(ulong, out LocalDate), which check the sentinel.

WireSize

The struct's exact size on the wire, in bytes, excluding any trailing ts_out.

public static int WireSize { get; }

Property Value

int

Methods

HasRType(RType)

Reports whether SystemMsg is the layout for records carrying rtype.

public static bool HasRType(RType rtype)

Parameters

rtype RType

The record type read from a record header.

Returns

bool

true if rtype is one of the record types this struct decodes. This is necessary but not sufficient to identify the record — see the remarks on IRecord<TSelf>.