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ComposeUI

Observability

ADR ID
adr-006
Status
Accepted
Scope
global
Deciders
github group
Date
6/30/2021

Context

Observability is the ability to infer internal states of a system based on the system’s external outputs. Observability is achieved through collection, correlation and interpretation of the three data domains which are also referred to as three pillars of observability: metrics, tracing and logs. ComposeUI needs to collect and emit these data to provide the ability for users

  • to have access to more accurate information about the system
  • to make monitoring and troubleshooting more efficient
  • to measure their service’s behavior and to evaluate whether their system has been running within SLO (Service Level Objective)

Decision

For observability we plan to use the open source OpenTelemetry observability framework. It is available in all the main programming languages. It offers a single set of APIs and libraries that standardize how to collect and transfer telemetry data. It is vendor neutral so users can send telemetry data to distinct backends of their choice. It improves observability by bringign together traces, logs and metrics from across applications and services in a correlated manner.

  • Metrics For metrics the prometheus .net package is going to be used as long as the OpenTelemetry metrics library reaches GA.

  • Tracing ComposeUI is going to be instrumented using System.Diagnostics.Activity class. This way, users can collect distributed trace information using OpenTelemetry.

  • Logs ComposeUI logs are going to be enriched with trace context in order to correlate traces with logs.

Consequences

  • OpenTelemetry provides a unified standard for creating and ingesting telemetry data.
  • It is able to provide developers and site reliability engineers with a more complete impression of app performance than was previously provided by basic monitoring.
  • It helps achieve business objectives.
  • Enables developers, security analysts and product managers to better understand and fix problems in the app that could have a negative impact on the business.