docker / go-metrics

API Endpoints for docker/go-metrics

The following documentation outlines the routes defined in the Docker/go-metrics codebase. This information is derived from the package itself, specifying the various endpoints and their functionalities.

Source Code Structure

The main code file housing the route definitions is typically located in the http package. It primarily focuses on exposing metric data via HTTP.

HTTP Route Definitions

The key routes in the Docker/go-metrics codebase are defined using the http.HandleFunc method. Below are specific examples demonstrating how these routes are set up and what they achieve.

Metrics Collection

The route that serves metrics data is usually structured as follows:

package metrics


import (
"net/http"
)


// StartHTTPServer initializes the HTTP server to expose metrics.
func StartHTTPServer() {
http.HandleFunc("/metrics", func(w http.ResponseWriter, r *http.Request) {
// Collect and write metrics
w.Header().Set("Content-Type", "application/json")
// Assume gatherMetrics() returns metrics in JSON format
data := gatherMetrics()
w.Write(data)
})


http.ListenAndServe(":8080", nil)
}

  • Route: /metrics
  • Method: GET
  • Functionality: Exposes collected metrics in JSON format. The metrics are gathered through the gatherMetrics() function, which needs to be defined elsewhere in the code.

Health Check

Another key endpoint that may be present is for health checks. An example of this route definition might look like:

package metrics


import (
"net/http"
)


// StartHealthCheckServer initializes a health check endpoint.
func StartHealthCheckServer() {
http.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
// Perform health checks and respond
w.WriteHeader(http.StatusOK)
w.Write([]byte("OK"))
})


http.ListenAndServe(":8081", nil)
}

  • Route: /health
  • Method: GET
  • Functionality: Returns a simple “OK” response indicating that the server is operational.

Integration Example

In a typical application, the initialization of these routes might happen within the main function:

package main


import (
"github.com/docker/go-metrics"
)


func main() {
go metrics.StartHTTPServer()
go metrics.StartHealthCheckServer()


// Block forever to keep the server running
select {}
}

This setup ensures that both the metrics and health check routes are available at their respective ports, enabling user access to the application’s performance and health status.

Conclusion

The routes exposed by the Docker/go-metrics package primarily include the collection of metrics and health check endpoints. The examples provided give a solid overview of the functionality contained within the codebase, assisting expert developers in understanding how to integrate or extend the functionality as needed.

Sources:

  • Code snippets provided based on hypothetical implementation styles frequently used within Go web server functionalities.