From 3d98195772e0dd3f8dd6f1642ab4fe954d92cc5d Mon Sep 17 00:00:00 2001
From: Robert Jacob <xperimental@solidproject.de>
Date: Sun, 21 Jun 2020 15:50:29 +0200
Subject: [PATCH] Make stale age configurable

---
 collector.go   | 13 +++++--------
 config.go      | 27 ++++++++++++++++++++++-----
 config_test.go | 12 ++++++++----
 3 files changed, 35 insertions(+), 17 deletions(-)

diff --git a/collector.go b/collector.go
index 1e675fa..f86581d 100644
--- a/collector.go
+++ b/collector.go
@@ -8,10 +8,6 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-const (
-	staleDataThreshold = 30 * time.Minute
-)
-
 var (
 	netatmoUp = prometheus.NewGauge(prometheus.GaugeOpts{
 		Name: "netatmo_up",
@@ -97,8 +93,9 @@ var (
 )
 
 type netatmoCollector struct {
-	log    logrus.FieldLogger
-	client *netatmo.Client
+	log            logrus.FieldLogger
+	staleThreshold time.Duration
+	client         *netatmo.Client
 }
 
 func (c *netatmoCollector) Describe(dChan chan<- *prometheus.Desc) {
@@ -140,8 +137,8 @@ func (c *netatmoCollector) collectData(ch chan<- prometheus.Metric, device *neta
 	}
 
 	date := time.Unix(*data.LastMeasure, 0)
-	if time.Since(date) > staleDataThreshold {
-		c.log.Warnf("Data is stale: %s > %s", time.Since(date), staleDataThreshold)
+	if time.Since(date) > c.staleThreshold {
+		c.log.Warnf("Data is stale: %s > %s", time.Since(date), c.staleThreshold)
 		return
 	}
 
diff --git a/config.go b/config.go
index 1de445d..1f9a960 100644
--- a/config.go
+++ b/config.go
@@ -3,6 +3,7 @@ package main
 import (
 	"errors"
 	"fmt"
+	"time"
 
 	netatmo "github.com/exzz/netatmo-api-go"
 	"github.com/sirupsen/logrus"
@@ -12,6 +13,7 @@ import (
 const (
 	envVarListenAddress       = "NETATMO_EXPORTER_ADDR"
 	envVarLogLevel            = "NETATMO_LOG_LEVEL"
+	envVarStaleDuration       = "NETATMO_AGE_STALE"
 	envVarNetatmoClientID     = "NETATMO_CLIENT_ID"
 	envVarNetatmoClientSecret = "NETATMO_CLIENT_SECRET"
 	envVarNetatmoUsername     = "NETATMO_CLIENT_USERNAME"
@@ -19,16 +21,20 @@ const (
 
 	flagListenAddress       = "addr"
 	flagLogLevel            = "log-level"
+	flagStaleDuration       = "age-stale"
 	flagNetatmoClientID     = "client-id"
 	flagNetatmoClientSecret = "client-secret"
 	flagNetatmoUsername     = "username"
 	flagNetatmoPassword     = "password"
+
+	defaultStaleDuration = 30 * time.Minute
 )
 
 var (
 	defaultConfig = config{
-		Addr:     ":9210",
-		LogLevel: logLevel(logrus.InfoLevel),
+		Addr:          ":9210",
+		LogLevel:      logLevel(logrus.InfoLevel),
+		StaleDuration: defaultStaleDuration,
 	}
 
 	errNoBinaryName          = errors.New("need the binary name as first argument")
@@ -60,9 +66,10 @@ func (l *logLevel) Set(value string) error {
 }
 
 type config struct {
-	Addr     string
-	LogLevel logLevel
-	Netatmo  netatmo.Config
+	Addr          string
+	LogLevel      logLevel
+	StaleDuration time.Duration
+	Netatmo       netatmo.Config
 }
 
 func parseConfig(args []string, getenv func(string) string) (config, error) {
@@ -75,6 +82,7 @@ func parseConfig(args []string, getenv func(string) string) (config, error) {
 	flagSet := pflag.NewFlagSet(args[0], pflag.ExitOnError)
 	flagSet.StringVarP(&cfg.Addr, flagListenAddress, "a", cfg.Addr, "Address to listen on.")
 	flagSet.Var(&cfg.LogLevel, flagLogLevel, "Sets the minimum level output through logging.")
+	flagSet.DurationVar(&cfg.StaleDuration, flagStaleDuration, cfg.StaleDuration, "Data age to consider as stale. Stale data does not create metrics anymore.")
 	flagSet.StringVarP(&cfg.Netatmo.ClientID, flagNetatmoClientID, "i", cfg.Netatmo.ClientID, "Client ID for NetAtmo app.")
 	flagSet.StringVarP(&cfg.Netatmo.ClientSecret, flagNetatmoClientSecret, "s", cfg.Netatmo.ClientSecret, "Client secret for NetAtmo app.")
 	flagSet.StringVarP(&cfg.Netatmo.Username, flagNetatmoUsername, "u", cfg.Netatmo.Username, "Username of NetAtmo account.")
@@ -119,6 +127,15 @@ func applyEnvironment(cfg *config, getenv func(string) string) error {
 		}
 	}
 
+	if envStaleDuration := getenv(envVarStaleDuration); envStaleDuration != "" {
+		duration, err := time.ParseDuration(envStaleDuration)
+		if err != nil {
+			return err
+		}
+
+		cfg.StaleDuration = duration
+	}
+
 	if envClientID := getenv(envVarNetatmoClientID); envClientID != "" {
 		cfg.Netatmo.ClientID = envClientID
 	}
diff --git a/config_test.go b/config_test.go
index b496000..1f19226 100644
--- a/config_test.go
+++ b/config_test.go
@@ -3,6 +3,7 @@ package main
 import (
 	"reflect"
 	"testing"
+	"time"
 
 	netatmo "github.com/exzz/netatmo-api-go"
 	"github.com/sirupsen/logrus"
@@ -38,8 +39,9 @@ func TestParseConfig(t *testing.T) {
 			},
 			env: map[string]string{},
 			wantConfig: config{
-				Addr:     defaultConfig.Addr,
-				LogLevel: logLevel(logrus.InfoLevel),
+				Addr:          defaultConfig.Addr,
+				LogLevel:      logLevel(logrus.InfoLevel),
+				StaleDuration: defaultStaleDuration,
 				Netatmo: netatmo.Config{
 					ClientID:     "id",
 					ClientSecret: "secret",
@@ -57,14 +59,16 @@ func TestParseConfig(t *testing.T) {
 			env: map[string]string{
 				envVarListenAddress:       ":8080",
 				envVarLogLevel:            "debug",
+				envVarStaleDuration:       "10m",
 				envVarNetatmoClientID:     "id",
 				envVarNetatmoClientSecret: "secret",
 				envVarNetatmoUsername:     "username",
 				envVarNetatmoPassword:     "password",
 			},
 			wantConfig: config{
-				Addr:     ":8080",
-				LogLevel: logLevel(logrus.DebugLevel),
+				Addr:          ":8080",
+				LogLevel:      logLevel(logrus.DebugLevel),
+				StaleDuration: 10 * time.Minute,
 				Netatmo: netatmo.Config{
 					ClientID:     "id",
 					ClientSecret: "secret",