postgres_exporter/config/config.go

121 lines
2.8 KiB
Go

// Copyright 2022 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package config
import (
"fmt"
"log/slog"
"os"
"sync"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promauto"
"gopkg.in/yaml.v3"
)
var (
configReloadSuccess = promauto.NewGauge(prometheus.GaugeOpts{
Namespace: "postgres_exporter",
Name: "config_last_reload_successful",
Help: "Postgres exporter config loaded successfully.",
})
configReloadSeconds = promauto.NewGauge(prometheus.GaugeOpts{
Namespace: "postgres_exporter",
Name: "config_last_reload_success_timestamp_seconds",
Help: "Timestamp of the last successful configuration reload.",
})
)
type Config struct {
AuthModules map[string]AuthModule `yaml:"auth_modules"`
}
type AuthModule struct {
Type string `yaml:"type"`
UserPass UserPass `yaml:"userpass,omitempty"`
// Add alternative auth modules here
Options map[string]string `yaml:"options"`
}
type UserPass struct {
Username string `yaml:"username"`
Password string `yaml:"password"`
}
type Handler struct {
sync.RWMutex
Config *Config
}
func (ch *Handler) GetConfig() *Config {
ch.RLock()
defer ch.RUnlock()
return ch.Config
}
func (ch *Handler) ReloadConfig(f string, logger *slog.Logger) error {
config := &Config{}
var err error
defer func() {
if err != nil {
configReloadSuccess.Set(0)
} else {
configReloadSuccess.Set(1)
configReloadSeconds.SetToCurrentTime()
}
}()
yamlReader, err := os.Open(f)
if err != nil {
return fmt.Errorf("Error opening config file %q: %s", f, err)
}
defer yamlReader.Close()
decoder := yaml.NewDecoder(yamlReader)
decoder.KnownFields(true)
if err = decoder.Decode(config); err != nil {
return fmt.Errorf("Error parsing config file %q: %s", f, err)
}
ch.Lock()
ch.Config = config
ch.Unlock()
return nil
}
func (m AuthModule) ConfigureTarget(target string) (DSN, error) {
dsn, err := dsnFromString(target)
if err != nil {
return DSN{}, err
}
// Set the credentials from the authentication module
// TODO(@sysadmind): What should the order of precedence be?
if m.Type == "userpass" {
if m.UserPass.Username != "" {
dsn.username = m.UserPass.Username
}
if m.UserPass.Password != "" {
dsn.password = m.UserPass.Password
}
}
for k, v := range m.Options {
dsn.query.Set(k, v)
}
return dsn, nil
}