Go implementation of AWS CloudWatch Embedded Metric Format
It's aim is to simplify reporting metrics to CloudWatch:
- using EMF avoids additional HTTP API calls to CloudWatch as metrics are logged in JSON format to stdout
- no need for additional dependencies in your services (or mocks in tests) to report metrics from inside your code
- built in support for default dimensions and properties for Lambda functions
Supports namespaces, setting dimensions and properties as well as different contexts (at least partially).
go get github.com/prozz/aws-embedded-metrics-golangemf.New().Namespace("mtg").Metric("totalWins", 1500).Log()
emf.New().Dimension("colour", "red").
MetricAs("gameLength", 2, emf.Seconds).Log()
emf.New().DimensionSet(
emf.NewDimension("format", "edh"),
emf.NewDimension("commander", "Muldrotha")).
MetricAs("wins", 1499, emf.Count).Log()
You may also use the lib together with defer.
m := emf.New() // sets up whatever you fancy here
defer m.Log()
// any reporting metrics calls
Customizing the logger:
emf.New(
emf.WithWriter(os.Stderr), // Log to stderr.
emf.WithTimestamp(time.Now().Add(-time.Hour)), // Record past metrics.
emf.WithoutDimensions(), // Do not include useful Lambda related dimensions.
emf.WithLogGroup("my-logs") // Add specific log group.
)
Functions for reporting metrics:
func Metric(name string, value int)
func Metrics(m map[string]int)
func MetricAs(name string, value int, unit MetricUnit)
func MetricsAs(m map[string]int, unit MetricUnit)
func MetricFloat(name string, value float64)
func MetricsFloat(m map[string]float64)
func MetricFloatAs(name string, value float64, unit MetricUnit)
func MetricsFloatAs(m map[string]float64, unit MetricUnit)
Functions for setting up dimensions:
func Dimension(key, value string)
func DimensionSet(dimensions ...Dimension) // use `func NewDimension` for creating one
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change. Please make sure to update tests.