Files
goplt/internal/metrics/metrics.go
0x1d 52d48590ae fix: resolve all linting and formatting issues
- Fix error return value checks (errcheck)
- Fix unused parameters by using underscore prefix
- Add missing package comments to all packages
- Fix context key type issue in middleware (use typed contextKey)
- Replace deprecated trace.NewNoopTracerProvider with noop.NewTracerProvider
- Fix embedded field selector in database client
- Remove trailing whitespace
- Remove revive linter (as requested) to avoid stuttering warnings for public API interfaces

All linting and formatting checks now pass.
2025-11-05 20:48:59 +01:00

98 lines
2.5 KiB
Go

// Package metrics provides Prometheus metrics collection and instrumentation.
package metrics
import (
"net/http"
"time"
"github.com/gin-gonic/gin"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
)
// Metrics holds all Prometheus metrics.
type Metrics struct {
httpRequestDuration *prometheus.HistogramVec
httpRequestTotal *prometheus.CounterVec
httpErrorsTotal *prometheus.CounterVec
registry *prometheus.Registry
}
// NewMetrics creates a new metrics registry with all metrics.
func NewMetrics() *Metrics {
registry := prometheus.NewRegistry()
m := &Metrics{
registry: registry,
httpRequestDuration: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "http_request_duration_seconds",
Help: "HTTP request duration in seconds",
Buckets: prometheus.DefBuckets,
},
[]string{"method", "path", "status"},
),
httpRequestTotal: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "http_requests_total",
Help: "Total number of HTTP requests",
},
[]string{"method", "path", "status"},
),
httpErrorsTotal: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "http_errors_total",
Help: "Total number of HTTP errors",
},
[]string{"method", "path", "status"},
),
}
// Register all metrics
registry.MustRegister(m.httpRequestDuration)
registry.MustRegister(m.httpRequestTotal)
registry.MustRegister(m.httpErrorsTotal)
return m
}
// HTTPMiddleware returns a Gin middleware for collecting HTTP metrics.
func (m *Metrics) HTTPMiddleware() gin.HandlerFunc {
return func(c *gin.Context) {
start := time.Now()
// Process request
c.Next()
// Calculate duration
duration := time.Since(start).Seconds()
// Get request details
method := c.Request.Method
path := c.FullPath()
if path == "" {
path = c.Request.URL.Path
}
status := c.Writer.Status()
// Record metrics
m.httpRequestDuration.WithLabelValues(method, path, http.StatusText(status)).Observe(duration)
m.httpRequestTotal.WithLabelValues(method, path, http.StatusText(status)).Inc()
// Record errors (4xx and 5xx)
if status >= 400 {
m.httpErrorsTotal.WithLabelValues(method, path, http.StatusText(status)).Inc()
}
}
}
// Handler returns an HTTP handler for the /metrics endpoint.
func (m *Metrics) Handler() http.Handler {
return promhttp.HandlerFor(m.registry, promhttp.HandlerOpts{})
}
// Registry returns the Prometheus registry.
func (m *Metrics) Registry() *prometheus.Registry {
return m.registry
}