feat: Extract df check config into hcl config file

cmd/main.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"context"
-	"encoding/json"
 	"flag"
 	"fmt"
 	"go/slack-bot/pkg/check"
@@ -17,11 +16,13 @@ import (
 	"github.com/hashicorp/hcl/v2/hclsyntax"
 )
 
+//SlackConf bot global configuration
 type SlackConf struct {
-	BotID         string `hcl:"bot_id"`
-	DestChannelID string `hcl:"dest_channel_id"`
-	WebhookID     string `hcl:"webhook_id"`
-	DryRun        *bool  `hcl:"dry_run"`
+	BotID         string              `hcl:"bot_id"`
+	DestChannelID string              `hcl:"dest_channel_id"`
+	WebhookID     string              `hcl:"webhook_id"`
+	DryRun        *bool               `hcl:"dry_run"`
+	Df            []check.DfParameter `hcl:"df,block"`
 }
 
 func main() {
@@ -32,40 +33,20 @@ func main() {
 	conf := ParseConfiguration(configFile)
 	slackNotifier := notify.NewSlackNotifier(conf.BotID, conf.DestChannelID, conf.WebhookID)
 
-	dfChecker := check.NewDfChecker("disk is full", "bash", "-c", "df | grep -v 'auto_home'")
+	dfChecker := check.NewDfChecker()
 
-	msg := dfChecker.Check(func(stdout string) notify.Message {
-		parsedDf, err := dfChecker.Parse(stdout)
-		if err != nil {
-			return notify.Message{
-				Content:      fmt.Sprint("disk is full : ", err),
-				ShouldNotify: true,
-			}
-		} else {
-			casted := parsedDf.(check.DfOut)
-			shouldNotify := check.FileSystemChecker("devfs", 70, casted)
-			if shouldNotify {
-				j, err := json.MarshalIndent(casted, "", "    ")
-				if err != nil {
-					return notify.Message{
-						Content:      fmt.Sprint("disk is full : ", err),
-						ShouldNotify: true,
-					}
-				}
-				return notify.Message{
-					Content:      fmt.Sprintf("disk is full : ```%s```\n", j),
-					ShouldNotify: true,
-				}
-			} else {
-				return notify.Message{
-					ShouldNotify: false,
-				}
-			}
+	msg := dfChecker.Check(func(stdout string) []notify.Message {
+		var messages []notify.Message
+		parsedDf := dfChecker.Parse(stdout)
+		casted := parsedDf.(check.DfStdout)
+		for _, dfCheck := range conf.Df {
+			messages = append(messages, dfChecker.FileSystemUsedCheck(casted, dfCheck))
 		}
+		return messages
 	})
 
 	dryRunCtx := context.WithValue(context.Background(), notify.DryRunContextKey, conf.DryRun)
-	slackNotifier.Notify(dryRunCtx, msg)
+	slackNotifier.Notify(dryRunCtx, msg...)
 }
 
 //ParseConfiguration take filename path and parse it to Config.SlackConf

config.sample.hcl

@@ -1,3 +1,8 @@
 bot_id = ""
 dest_channel_id = ""
-webhook_id = ""
+webhook_id = ""
+
+df {
+    fs_name = "<filesystem name>"
+    critical = "<used pourcent>"
+}

manifests/common.tf

@@ -14,6 +14,11 @@ resource "kubernetes_config_map" "slack_bot_config" {
 bot_id = "${var.bot_id}"
 dest_channel_id = "${var.dest_channel_id}"
 webhook_id = "${var.webhook_id}"
+
+df {
+    fs_name = "/dev/mapper/vg1-data--kube"
+    critical = "85"
+}
 EOF
   }
 }

pkg/check/command.go

@@ -8,13 +8,13 @@ import (
 
 //Checker representation of check set
 type Checker interface {
-	Check(f func(stdout string) notify.Message) notify.Message
+	Check(f func(stdout string) []notify.Message) []notify.Message
 }
 
 //AdvancedChecker like Checker except contain Parsing step
 type AdvancedChecker interface {
 	Checker
-	Parse(stdout string) (interface{}, error)
+	Parse(stdout string) interface{}
 }
 
 //CliChecker implement checker with cli command
@@ -32,16 +32,18 @@ func NewCliChecker(alertingMessage string, command ...string) Checker {
 }
 
 //Check function use to run cli call to check some parameter
-func (cc *CliChecker) Check(f func(stdout string) notify.Message) notify.Message {
-	message := notify.Message{ShouldNotify: false}
+func (cc *CliChecker) Check(f func(stdout string) []notify.Message) []notify.Message {
+	message := []notify.Message{}
 
 	out, err := exec.Command(cc.command[0], cc.command[1:]...).CombinedOutput()
 	if err != nil {
 		// command fail notify with error
-		message = notify.Message{
-			Content:      fmt.Sprint(cc.alertingMessage, " : ", string(out), err),
-			ShouldNotify: true,
-		}
+		message = append(message,
+			notify.Message{
+				Content:      fmt.Sprint(cc.alertingMessage, " : ", string(out), err),
+				ShouldNotify: true,
+			},
+		)
 	} else {
 		// command success check if condition required notify
 		message = f(string(out))

pkg/check/df.go

@@ -1,19 +1,23 @@
 package check
 
 import (
+	"fmt"
+	"go/slack-bot/pkg/notify"
 	"regexp"
 	"strconv"
 	"strings"
 )
 
+const dfMessage = "disk check"
+
 //DfChecker df command implementation of AdvancedChecker
 type DfChecker struct {
 	CliChecker
 	pourcentRegexMatcher *regexp.Regexp
 }
 
-type DfOut []DfOutLine
-type DfOutLine struct {
+type DfStdout []DfStdoutLine
+type DfStdoutLine struct {
 	Filesystem,
 	Size,
 	Used,
@@ -22,21 +26,26 @@ type DfOutLine struct {
 	Mounted      string
 }
 
-//NewDfChecker build new checker for df command
-func NewDfChecker(alertingMessage string, command ...string) AdvancedChecker {
+//DfParameter df check configuration
+type DfParameter struct {
+	FileSystemName   string `hcl:"fs_name"`
+	CriticalPourcent int    `hcl:"critical"`
+}
 
+//NewDfChecker build new checker for df command
+func NewDfChecker() *DfChecker {
 	return &DfChecker{
 		CliChecker: CliChecker{
-			alertingMessage: alertingMessage,
-			command:         command,
+			alertingMessage: dfMessage,
+			command:         []string{"bash", "-c", "df | grep -v 'auto_home'"},
 		},
 		pourcentRegexMatcher: regexp.MustCompile(`(?P<value>.*)%`),
 	}
 }
 
-//DfParser parse df stdout
-func (dc *DfChecker) Parse(stdout string) (interface{}, error) {
-	var dfOut DfOut
+//Parse df command stdout
+func (dc *DfChecker) Parse(stdout string) interface{} {
+	var dfOut DfStdout
 
 	for _, line := range strings.Split(stdout, "\n")[1:] {
 		if strings.TrimSpace(line) == "" {
@@ -53,10 +62,10 @@ func (dc *DfChecker) Parse(stdout string) (interface{}, error) {
 		valueIndex := dc.pourcentRegexMatcher.SubexpIndex("value")
 		v, err := strconv.Atoi(dc.pourcentRegexMatcher.FindStringSubmatch(cleanedColumns[4])[valueIndex])
 		if err != nil {
-			return dfOut, err
+			v = -1
 		}
 		// extract pourcent used from columns
-		dfOut = append(dfOut, DfOutLine{
+		dfOut = append(dfOut, DfStdoutLine{
 			Filesystem:   cleanedColumns[0],
 			Size:         cleanedColumns[1],
 			Used:         cleanedColumns[2],
@@ -65,16 +74,24 @@ func (dc *DfChecker) Parse(stdout string) (interface{}, error) {
 			Mounted:      cleanedColumns[len(cleanedColumns)-1],
 		})
 	}
-	return dfOut, nil
+	return dfOut
 }
 
-func FileSystemChecker(fileSystemName string, criticalPourcent int, dfOut DfOut) bool {
+//FileSystemUsedCheck take dfStdout and check if filesystem is full over than criticalPourcent value
+func (dc *DfChecker) FileSystemUsedCheck(dfOut DfStdout, param DfParameter) notify.Message {
+	message := notify.Message{
+		ShouldNotify: false,
+	}
 	for _, line := range dfOut {
-		if line.Filesystem == fileSystemName {
-			if line.PourcentUsed > criticalPourcent {
-				return true
+		if line.Filesystem == param.FileSystemName {
+			if line.PourcentUsed > param.CriticalPourcent {
+				text := fmt.Sprintf("%s : fs '%s' critial %d%%, used %d%% \n", dc.alertingMessage, line.Filesystem, param.CriticalPourcent, line.PourcentUsed)
+				message = notify.Message{
+					Content:      text,
+					ShouldNotify: true,
+				}
 			}
 		}
 	}
-	return false
+	return message
 }

pkg/notify/slack.go

@@ -42,10 +42,18 @@ func NewSlackNotifier(BotID, DestChannelID, WebhookID string) *SlackNotifier {
 }
 
 //Notify send notification to channel
-func (sn *SlackNotifier) Notify(ctx context.Context, message Message) {
-	if message.ShouldNotify {
+func (sn *SlackNotifier) Notify(ctx context.Context, messages ...Message) {
+	shouldNotify := false
+	var content string
+	for _, message := range messages {
+		if message.ShouldNotify {
+			shouldNotify = true
+			content = fmt.Sprintf("%s\n%s", content, message.Content)
+		}
+	}
+	if shouldNotify {
 		msg := &slack.WebhookMessage{
-			Text: message.Content,
+			Text: content,
 		}
 
 		url := fmt.Sprintf("https://%s/%s/%s/%s", slackHookBaseURL, sn.BotID, sn.DestChannelID, sn.WebhookID)