minitor-go/config.go
Ian Fijolek 570ad1e2ec
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Remove redundant logging
2024-11-15 16:40:54 -08:00

149 lines
3.7 KiB
Go

package main
import (
"errors"
"fmt"
"time"
"git.iamthefij.com/iamthefij/slog"
"github.com/hashicorp/hcl/v2/hclsimple"
)
var (
ErrLoadingConfig = errors.New("Failed to load or parse configuration")
ErrConfigInit = errors.New("Failed to initialize configuration")
ErrInvalidConfig = errors.New("Invalid configuration")
ErrNoAlerts = errors.New("No alerts provided")
ErrInvalidAlert = errors.New("Invalid alert configuration")
ErrNoMonitors = errors.New("No monitors provided")
ErrInvalidMonitor = errors.New("Invalid monitor configuration")
ErrUnknownAlert = errors.New("Unknown alert")
)
// Config type is contains all provided user configuration
type Config struct {
CheckIntervalStr string `hcl:"check_interval"`
CheckInterval time.Duration
DefaultAlertAfter int `hcl:"default_alert_after,optional"`
DefaultAlertEvery *int `hcl:"default_alert_every,optional"`
DefaultAlertDown []string `hcl:"default_alert_down,optional"`
DefaultAlertUp []string `hcl:"default_alert_up,optional"`
Monitors []*Monitor `hcl:"monitor,block"`
Alerts []*Alert `hcl:"alert,block"`
alertLookup map[string]*Alert
}
// Init performs extra initialization on top of loading the config from file
func (config *Config) Init() (err error) {
config.CheckInterval, err = time.ParseDuration(config.CheckIntervalStr)
if err != nil {
return fmt.Errorf("failed to parse top level check_interval duration: %w", err)
}
if config.DefaultAlertAfter == 0 {
minAlertAfter := 1
config.DefaultAlertAfter = minAlertAfter
}
for _, monitor := range config.Monitors {
if err = monitor.Init(
config.DefaultAlertAfter,
config.DefaultAlertEvery,
config.DefaultAlertDown,
config.DefaultAlertUp,
); err != nil {
return
}
}
err = config.BuildAllTemplates()
return
}
// IsValid checks config validity and returns true if valid
func (config Config) IsValid() error {
var err error
// Validate alerts
if len(config.Alerts) == 0 {
err = errors.Join(err, ErrNoAlerts)
}
for _, alert := range config.Alerts {
err = errors.Join(err, alert.Validate())
}
// Validate monitors
if len(config.Monitors) == 0 {
err = errors.Join(err, ErrNoMonitors)
}
for _, monitor := range config.Monitors {
err = errors.Join(err, monitor.Validate())
// Check that all Monitor alerts actually exist
for _, isUp := range []bool{true, false} {
for _, alertName := range monitor.GetAlertNames(isUp) {
if _, ok := config.GetAlert(alertName); !ok {
err = errors.Join(
err,
fmt.Errorf("%w: %s. %w: %s", ErrInvalidMonitor, monitor.Name, ErrUnknownAlert, alertName),
)
}
}
}
}
return err
}
// GetAlert returns an alert by name
func (c Config) GetAlert(name string) (*Alert, bool) {
if c.alertLookup == nil {
c.alertLookup = map[string]*Alert{}
for _, alert := range c.Alerts {
c.alertLookup[alert.Name] = alert
}
}
v, ok := c.alertLookup[name]
return v, ok
}
// BuildAllTemplates builds all alert templates
func (c *Config) BuildAllTemplates() (err error) {
for _, alert := range c.Alerts {
if err = alert.BuildTemplates(); err != nil {
return
}
}
return
}
// LoadConfig will read config from the given path and parse it
func LoadConfig(filePath string) (Config, error) {
var config Config
if err := hclsimple.DecodeFile(filePath, nil, &config); err != nil {
return config, errors.Join(ErrLoadingConfig, err)
}
slog.Debugf("Config values:\n%v\n", config)
// Finish initializing configuration
if err := config.Init(); err != nil {
return config, errors.Join(ErrConfigInit, err)
}
if err := config.IsValid(); err != nil {
return config, errors.Join(ErrInvalidConfig, err)
}
return config, nil
}