metrics

func New ¶

func New() (echo.MiddlewareFunc, error)

New returns a new instance of the middleware function with default configuration.

The returned middleware function measures the latency, request count, request size, and response size of HTTP requests handled by an Echo server. It uses OpenTelemetry to create metrics and records the measurements for each request.

The default configuration uses the following settings:

• MeterProvider: The default OpenTelemetry meter provider obtained from otel.GetMeterProvider().
• Skipper: The default Echo middleware skipper obtained from middleware.DefaultSkipper.
• MeterName: The default meter name "echo_http_metrics".
• InstrumentNamePrefix: The default instrument name prefix "echo".

Returns:

• echo.MiddlewareFunc: The middleware function that can be used with Echo's Use() method.
• error: An error if there was a problem creating the metrics or configuring the middleware.

Example usage:

e := echo.New()
e.Use(New())

Note: This function is a convenience wrapper around NewWithConfig() and provides default configuration values. If you need to customize the configuration, use NewWithConfig() instead.

See Also:

• NewWithConfig: Creates a new instance of the middleware function with custom configuration.
• Config: The configuration struct used to customize the middleware behavior.

func NewMeter ¶

func NewMeter(mp *sdkmetric.MeterProvider) metric.Meter

func NewMeterProvider ¶

func NewMeterProvider(res *sdkresource.Resource, exporter sdkmetric.Exporter, exportInterval time.Duration, memStatsInterval time.Duration) (*sdkmetric.MeterProvider, error)

func NewOTLPMetricExporter ¶

func NewOTLPMetricExporter(ctx context.Context, otlpEndpoint string, exportTimeout time.Duration) (*otlpmetrichttp.Exporter, error)

func NewStdoutMetricExporter ¶

func NewStdoutMetricExporter() (sdkmetric.Exporter, error)

func NewWithConfig ¶

func NewWithConfig(config Config) (echo.MiddlewareFunc, error)

NewWithConfig is a function that creates and returns an Echo middleware function with the given configuration.

Parameters:

• config: A Config struct that contains the configuration options for the middleware.

Returns:

• echo.MiddlewareFunc: The Echo middleware function.
• error: An error if any error occurs during the creation of the middleware.

The NewWithConfig function initializes the required metrics for monitoring HTTP requests and responses. It creates histograms for request duration, request count, request size, and response size. The function then returns a middleware function that records the metrics for each incoming request and response.

The middleware function measures the duration of each request, the count of requests, the size of the request, and the size of the response. It records these metrics using the configured meter provider and attribute set. The function also handles any errors that occur during the execution of the next handler and sets the appropriate HTTP status code.

Example usage:

config := Config{
	Skipper: middleware.DefaultSkipper,
	MeterProvider: otel.GetMeterProvider(),
	InstrumentNamePrefix: "myapp",
}

middlewareFunc, err := NewWithConfig(config)

if err != nil {
	log.Fatal(err)
}

e := echo.New()
e.Use(middlewareFunc)

Note: The NewWithConfig function assumes that the required dependencies, such as the Echo framework and OpenTelemetry meter provider, are already imported and configured.