reference prometheus metrics

PromQL Reference

PromQL is a query language for Prometheus monitoring system. It allows you to select and aggregate time series data in real time. PromQL is used to create dashboards in Grafana, and to create alerts with Alertmanager.

Basic Syntax

A basic PromQL query can be as simple as a metric name: http_requests_total. This will return the current value of the http_requests_total metric.

Data Types

PromQL supports a variety of data types:

  • Scalars: 1, 3.14, 0.5
  • Strings: "hello", "world"
  • Vectors: http_requests_total{job="api-server"}
  • Range Vectors: http_requests_total{job="api-server"}[5m]

Operators

PromQL supports a variety of operators:

  • Arithmetic: +, -, *, /, %, ^
  • Comparison: ==, !=, >, <, >=, <=
  • Logical: and, or, unless

Functions

PromQL includes a variety of functions, such as:

  • rate(v range-vector): calculates the per-second average rate of time series in a range vector
  • sum(v vector): calculates the sum of all values in the vector
  • avg(v vector): calculates the average of all values in the vector

Aggregation

PromQL allows you to aggregate time series: sum(http_requests_total) by (status). This will return the sum of http_requests_total for each status label value.

More Information

For more detailed information, refer to the official PromQL documentation and the example Prometheus queries.