Rig.TUnit.Observability.AppInsights 0.1.0-beta.2

Rig.TUnit.Observability.AppInsights

In-process Application Insights fixture with CapturingTelemetryChannel — zero network egress, deterministic assertions.

What this package is

A fixture that wires a real TelemetryClient to a CapturingTelemetryChannel — the client API is production-identical but the channel records every item into a thread-safe queue instead of sending to Azure. Tests assert via AppInsightsAssert.Event(…), .Dependency(…), .Exception<T>(…) with the familiar fluent shape.

When to use it

• Integration tests for services using Microsoft.ApplicationInsights.
• Verifying custom events and dependency tracking fire at the right points.
• Asserting exception telemetry is emitted with correct properties.
• Not for: E2E tests against real Azure — those require a real instrumentation key and network access.

Prerequisites

• .NET 10 SDK
• Microsoft.ApplicationInsights 2.x (transitive)

Quick start

using Rig.TUnit.Observability.AppInsights.Fixtures;

await using var fx = new AppInsightsFixture();
await fx.InitializeAsync();

fx.Client.TrackEvent("order.placed");

Options

Fixture + helper APIs

• Rig.TUnit.Observability.AppInsights.Fixtures.AppInsightsFixture
• Rig.TUnit.Observability.AppInsights.Options.AppInsightsFixtureOptions
• Rig.TUnit.Observability.AppInsights.Builder.AppInsightsRigBuilder
• Rig.TUnit.Observability.AppInsights.Channels.CapturingTelemetryChannel
• Rig.TUnit.Observability.AppInsights.Assertions.AppInsightsAssert

Per-test isolation

Each AppInsightsFixture owns its channel; captured items are never cross-test visible. Safe under full parallelism.

Parallelism + performance

• Fixture construction: ~2 ms.
• Track* call overhead: ~5 µs (no network).
• Safe under full parallelism.

Troubleshooting

• Telemetry not captured — ensure you are using fx.Client, not a TelemetryClient constructed elsewhere; only the fixture's client is wired to the capturing channel.
• AppInsightsAssert.Event(…).Exactly(1) fails with 0 — some telemetry is batched by the SDK; call fx.Client.Flush() before asserting.

See docs/troubleshooting.md#appinsights.

Provider quirks + edge cases

• The capturing channel stores items in a ConcurrentQueue — the assertion API LINQs over the snapshot, so very fast producers can observe a count mid-flight; always Flush() first.
• RoleName is set globally; parallel fixtures with different role names must not share a static TelemetryConfiguration.

Benchmarks

See AppInsightsBenchmarks.cs; baseline in benchmarks/baseline-005.json.

Related docs

• Architecture diagram
• Glossary
• Family base: Rig.TUnit.Observability

License

MIT. See LICENSE.