gotosocial/internal/api/metrics/metrics.go

58 lines
1.7 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package metrics
import (
"net/http"
"github.com/gin-gonic/gin"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
)
type Module struct {
handler http.Handler
}
func New() *Module {
// Let prometheus use "identity", ie., no compression,
// or "gzip", to match our own gzip compression middleware.
opts := promhttp.HandlerOpts{
OfferedCompressions: []promhttp.Compression{
promhttp.Identity,
promhttp.Gzip,
},
}
// Instrument handler itself.
handler := promhttp.InstrumentMetricHandler(
prometheus.DefaultRegisterer,
promhttp.HandlerFor(prometheus.DefaultGatherer, opts),
)
return &Module{
handler: handler,
}
}
func (m *Module) Route(attachHandler func(method string, path string, f ...gin.HandlerFunc) gin.IRoutes) {
attachHandler(http.MethodGet, "", func(c *gin.Context) {
// Defer all "/metrics" handling to prom.
m.handler.ServeHTTP(c.Writer, c.Request)
})
}