Class AppMetrics

Namespace

Virtufin.Api.Services

Assembly

Virtufin.Api.dll

Application-level metrics for the API gateway.

public static class AppMetrics

Inheritance

object

AppMetrics

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

Program.cs has registered AddMeter("Virtufin.Api") since OpenTelemetry was wired up, but nothing ever created that meter — the pipeline was configured and empty. This is the type that gives it something to export.

The meter name must stay in step with the AddMeter call; MeterName is referenced there so the two cannot drift.

Fields

MeterName

public const string MeterName = "Virtufin.Api"

Field Value

string

StateChangePublishFailures

State-change notifications that failed to publish after the state write had already succeeded — i.e. events silently lost.

public static readonly Counter<long> StateChangePublishFailures

Field Value

Counter<long>

Remarks

Publication is at-most-once and not atomic with the write (see the State Change Events requirement in the pubsub-topics spec). When this fires, the write stands and no subscriber is told: there is no retry, no dead letter, and the caller sees success — correctly, since failing the call would make them repeat a write that landed.

This counter exists to answer whether that gap needs closing. Closing it means a transactional outbox, which flips the guarantee to at-least-once and makes every subscriber's idempotency a breaking concern — worth it for a daily failure, not obviously worth it for a twice-a-year one. Nobody currently knows which this is.

StateChangePublishes

State-change notifications the gateway attempted to publish, by tier.

public static readonly Counter<long> StateChangePublishes

Field Value

Counter<long>

Remarks

The denominator for StateChangePublishFailures. A failure count without it says nothing about whether the gap is rare or routine.

Tier0

Tier 0: the shared state.change topic (infrastructure state).

public const string Tier0 = "tier0"

Field Value

string

Tier1

Tier 1: a caller-supplied event on a caller-chosen topic (domain state).

public const string Tier1 = "tier1"

Field Value

string

Methods

RecordStateChangePublishAttempt(string, string, string)

Records an attempted state-change publish.

public static void RecordStateChangePublishAttempt(string service, string action, string tier)

Parameters

service string

action string

tier string

RecordStateChangePublishFailure(string, string, string)

Records a state-change publish that failed after a successful write.

public static void RecordStateChangePublishFailure(string service, string action, string tier)

Parameters

service string

action string

tier string