From 141fe3485fec75ff08421e93f42f5bff2249e26b Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Sun, 18 Oct 2020 17:22:24 +0200
Subject: [PATCH] Add hourly hooks and improve command execution code

---
 config.go |  1 +
 go.mod    |  2 +-
 go.sum    |  4 ++--
 hooks.go  | 44 +++++++++++++++++++++++++-------------------
 main.go   |  3 +++
 5 files changed, 32 insertions(+), 22 deletions(-)

diff --git a/config.go b/config.go
index 6acdcb1..9dae141 100644
--- a/config.go
+++ b/config.go
@@ -106,6 +106,7 @@ type configUser struct {
 
 type configHooks struct {
 	Shell    string   `mapstructure:"shell"`
+	Hourly   []string `mapstructure:"hourly"`
 	PreStart []string `mapstructure:"prestart"`
 }
 
diff --git a/go.mod b/go.mod
index c40d20b..6002989 100644
--- a/go.mod
+++ b/go.mod
@@ -37,7 +37,7 @@ require (
 	github.com/yuin/goldmark-emoji v1.0.1
 	golang.org/x/crypto v0.0.0-20201016220609-9e8e0b390897
 	golang.org/x/net v0.0.0-20201016165138-7b1cca2348c0 // indirect
-	golang.org/x/sys v0.0.0-20201017003518-b09fb700fbb7 // indirect
+	golang.org/x/sys v0.0.0-20201018121011-98379d014ca7 // indirect
 	gopkg.in/check.v1 v1.0.0-20200902074654-038fdea0a05b // indirect
 	gopkg.in/ini.v1 v1.62.0 // indirect
 	gopkg.in/yaml.v2 v2.3.0 // indirect
diff --git a/go.sum b/go.sum
index 8a1924c..5858570 100644
--- a/go.sum
+++ b/go.sum
@@ -372,8 +372,8 @@ golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c h1:UIcGWL6/wpCfyGuJnRFJRurA+yj8RrW7Q6x2YMCXt6c=
 golang.org/x/sys v0.0.0-20200724161237-0e2f3a69832c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201017003518-b09fb700fbb7 h1:XtNJkfEjb4zR3q20BBBcYUykVOEMgZeIUOpBPfNYgxg=
-golang.org/x/sys v0.0.0-20201017003518-b09fb700fbb7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201018121011-98379d014ca7 h1:CNOpL+H7PSxBI7dF/EIUsfOguRSzWp6CQ91yxZE6PG4=
+golang.org/x/sys v0.0.0-20201018121011-98379d014ca7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
diff --git a/hooks.go b/hooks.go
index dcc5e47..d798e7e 100644
--- a/hooks.go
+++ b/hooks.go
@@ -1,10 +1,9 @@
 package main
 
 import (
-	"bytes"
-	"fmt"
 	"log"
 	"os/exec"
+	"time"
 )
 
 func preStartHooks() {
@@ -14,22 +13,29 @@ func preStartHooks() {
 	}
 }
 
-func executeCommand(cmd string) {
-	var stdout, stderr bytes.Buffer
-	parsed := exec.Command(appConfig.Hooks.Shell, "-c", cmd)
-	parsed.Stdout = &stdout
-	parsed.Stderr = &stderr
-	cmdErr := parsed.Run()
-	if cmdErr != nil {
-		fmt.Println("Executing command failed:")
-		fmt.Println(cmdErr.Error())
-	}
-	if stdout.Len() > 0 {
-		log.Println("Output:")
-		log.Print(stdout.String())
-	}
-	if stderr.Len() > 0 {
-		log.Println("Error:")
-		log.Print(stderr.String())
+func startHourlyHooks() {
+	for _, cmd := range appConfig.Hooks.Hourly {
+		go func(cmd string) {
+			run := func() {
+				log.Println("Executing hourly hook:", cmd)
+				executeCommand(cmd)
+			}
+			// Execute once
+			run()
+			// Start ticker and execute regularly
+			ticker := time.NewTicker(1 * time.Hour)
+			for range ticker.C {
+				run()
+			}
+		}(cmd)
 	}
 }
+
+func executeCommand(cmd string) {
+	out, err := exec.Command(appConfig.Hooks.Shell, "-c", cmd).CombinedOutput()
+	if err != nil {
+		log.Println("Failed to execute command:", err.Error())
+	}
+	log.Println("Output:")
+	log.Print(string(out))
+}
diff --git a/main.go b/main.go
index 86dc3ce..33e800f 100644
--- a/main.go
+++ b/main.go
@@ -51,6 +51,9 @@ func main() {
 		return
 	}
 
+	// Start cron hooks
+	startHourlyHooks()
+
 	// Prepare graceful shutdown
 	quit := make(chan os.Signal, 1)