tracker/server/prometheus/prometheus.go
2016-03-05 11:12:54 -05:00

87 lines
2.1 KiB
Go

// Copyright 2016 The Chihaya Authors. All rights reserved.
// Use of this source code is governed by the BSD 2-Clause license,
// which can be found in the LICENSE file.
// Package prometheus implements a chihaya Server for serving metrics to
// Prometheus.
package prometheus
import (
"errors"
"net/http"
"time"
"github.com/prometheus/client_golang/prometheus"
"github.com/tylerb/graceful"
"gopkg.in/yaml.v2"
"github.com/chihaya/chihaya"
"github.com/chihaya/chihaya/server"
"github.com/chihaya/chihaya/tracker"
)
func init() {
server.Register("prometheus", constructor)
}
func constructor(srvcfg *chihaya.ServerConfig, tkr *tracker.Tracker) (server.Server, error) {
cfg, err := NewServerConfig(srvcfg)
if err != nil {
return nil, errors.New("prometheus: invalid config: " + err.Error())
}
return &Server{
cfg: cfg,
}, nil
}
// ServerConfig represents the configuration options for a
// PrometheusServer.
type ServerConfig struct {
Addr string `yaml:"addr"`
ShutdownTimeout time.Duration `yaml:"shutdown_timeout"`
ReadTimeout time.Duration `yaml:"read_timeout"`
WriteTimeout time.Duration `yaml:"write_timeout"`
}
// NewServerConfig marshals a chihaya.ServerConfig and unmarshals it
// into a more specific prometheus ServerConfig.
func NewServerConfig(srvcfg *chihaya.ServerConfig) (*ServerConfig, error) {
bytes, err := yaml.Marshal(srvcfg.Config)
if err != nil {
return nil, err
}
var cfg ServerConfig
err = yaml.Unmarshal(bytes, &cfg)
if err != nil {
return nil, err
}
return &cfg, nil
}
// Server implements a chihaya Server for serving metrics to Prometheus.
type Server struct {
cfg *ServerConfig
grace *graceful.Server
}
var _ server.Server = &Server{}
func (s *Server) Start() {
s.grace = &graceful.Server{
Server: &http.Server{
Addr: s.cfg.Addr,
Handler: prometheus.Handler(),
ReadTimeout: s.cfg.ReadTimeout,
WriteTimeout: s.cfg.WriteTimeout,
},
Timeout: s.cfg.ShutdownTimeout,
NoSignalHandling: true,
}
}
func (s *Server) Stop() {
s.grace.Stop(s.cfg.ShutdownTimeout)
}