MetricFilter

Source: src/AWS/Logs/MetricFilter.ts

A CloudWatch Logs metric filter — extracts CloudWatch metrics from log events matching a filter pattern.

Extracting Metrics

Count Error Log Lines

const errors = yield* MetricFilter("ErrorCount", {
  logGroupName: logGroup.logGroupName,
  filterPattern: "?ERROR ?Error",
  metricTransformations: [
    {
      metricName: "ErrorCount",
      metricNamespace: "MyApp",
      metricValue: "1",
      defaultValue: 0,
    },
  ],
});

Extract a Latency Value from JSON Logs

const latency = yield* MetricFilter("RequestLatency", {
  logGroupName: logGroup.logGroupName,
  filterPattern: "{ $.latencyMs = * }",
  metricTransformations: [
    {
      metricName: "LatencyMs",
      metricNamespace: "MyApp",
      metricValue: "$.latencyMs",
      unit: "Milliseconds",
    },
  ],
});