minitor-go/config.go

102 lines
2.3 KiB
Go

package main
import (
"errors"
"io/ioutil"
"log"
"os"
"gopkg.in/yaml.v2"
)
// Config type is contains all provided user configuration
type Config struct {
CheckInterval int64 `yaml:"check_interval"`
Monitors []*Monitor
Alerts map[string]*Alert
}
// IsValid checks config validity and returns true if valid
func (config Config) IsValid() (isValid bool) {
isValid = true
// Validate monitors
if config.Monitors == nil || len(config.Monitors) == 0 {
log.Printf("ERROR: Invalid monitor configuration: Must provide at least one monitor")
isValid = false
}
for _, monitor := range config.Monitors {
if !monitor.IsValid() {
log.Printf("ERROR: Invalid monitor configuration: %s", monitor.Name)
isValid = false
}
// Check that all Monitor alerts actually exist
for _, isUp := range []bool{true, false} {
for _, alertName := range monitor.GetAlertNames(isUp) {
if _, ok := config.Alerts[alertName]; !ok {
log.Printf(
"ERROR: Invalid monitor configuration: %s. Unknown alert %s",
monitor.Name, alertName,
)
isValid = false
}
}
}
}
// Validate alerts
if config.Alerts == nil || len(config.Alerts) == 0 {
log.Printf("ERROR: Invalid alert configuration: Must provide at least one alert")
isValid = false
}
for _, alert := range config.Alerts {
if !alert.IsValid() {
log.Printf("ERROR: Invalid alert configuration: %s", alert.Name)
isValid = false
}
}
return
}
// Init performs extra initialization on top of loading the config from file
func (config *Config) Init() (err error) {
for name, alert := range config.Alerts {
alert.Name = name
if err = alert.BuildTemplates(); err != nil {
return
}
}
return
}
// LoadConfig will read config from the given path and parse it
func LoadConfig(filePath string) (config Config, err error) {
data, err := ioutil.ReadFile(filePath)
if err != nil {
return
}
// TODO: Decide if this is better expanded here, or only when executing
envExpanded := os.ExpandEnv(string(data))
err = yaml.Unmarshal([]byte(envExpanded), &config)
if err != nil {
return
}
if LogDebug {
log.Printf("DEBUG: Config values:\n%v\n", config)
}
if !config.IsValid() {
err = errors.New("Invalid configuration")
return
}
// Finish initializing configuration
err = config.Init()
return
}