Load config from disk|url, create incidents

- Resolve incidents after the monitor is up
- Example configuration
- Updated readme

.gitignore

@@ -1 +1,2 @@
-gin-bin
+gin-bin
+example.config.local.json

cachet/cachet.go

@@ -2,7 +2,5 @@ package cachet
 
 import "os"
 
-// apiUrl -> https://demo.cachethq.io/api
+var ApiUrl = os.Getenv("CACHET_API")
-// apiToken -> qwertyuiop
+var ApiToken = os.Getenv("CACHET_TOKEN")
-var apiUrl = os.Getenv("CACHET_API")
-var apiToken = os.Getenv("CACHET_TOKEN")

cachet/config.go

@@ -0,0 +1,74 @@
+package cachet
+
+import (
+	"os"
+	"fmt"
+	"flag"
+	"net/url"
+	"net/http"
+	"io/ioutil"
+	"encoding/json"
+)
+
+var Config CachetConfig
+
+type CachetConfig struct {
+	API_Url string `json:"api_url"`
+	API_Token string `json:"api_token"`
+	Monitors []*Monitor `json:"monitors"`
+}
+
+func init() {
+	var configPath string
+	flag.StringVar(&configPath, "c", "/etc/cachet-monitor.config.json", "Config path")
+	flag.Parse()
+
+	var data []byte
+
+	// test if its a url
+	_, err := url.ParseRequestURI(configPath)
+	if err == nil {
+		// download config
+		response, err := http.Get(configPath)
+		if err != nil {
+			fmt.Printf("Cannot download network config: %v\n", err)
+			os.Exit(1)
+		}
+
+		defer response.Body.Close()
+
+		data, _ = ioutil.ReadAll(response.Body)
+
+		fmt.Println("Downloaded network configuration.")
+	} else {
+		data, err = ioutil.ReadFile(configPath)
+		if err != nil {
+			fmt.Println("Config file '" + configPath + "' missing!")
+			os.Exit(1)
+		}
+	}
+
+	err = json.Unmarshal(data, &Config)
+
+	if err != nil {
+		fmt.Println("Cannot parse config!")
+		os.Exit(1)
+	}
+
+	if len(os.Getenv("CACHET_API")) > 0 {
+		Config.API_Url = os.Getenv("CACHET_API")
+	}
+	if len(os.Getenv("CACHET_TOKEN")) > 0 {
+		Config.API_Token = os.Getenv("CACHET_TOKEN")
+	}
+
+	if len(Config.API_Token) == 0 || len(Config.API_Url) == 0 {
+		fmt.Printf("API URL or API Token not set. cachet-monitor won't be able to report incidents.\n\nPlease set:\n CACHET_API and CACHET_TOKEN environment variable to override settings.\n\nGet help at https://github.com/CastawayLabs/cachet-monitor\n")
+		os.Exit(1)
+	}
+
+	if len(Config.Monitors) == 0 {
+		fmt.Printf("No monitors defined!\nSee sample configuration: https://github.com/CastawayLabs/cachet-monitor/blob/master/example.config.json\n")
+		os.Exit(1)
+	}
+}

cachet/incident.go

@@ -33,9 +33,9 @@ func (incident *Incident) Send() {
 
 	var req *http.Request
 	if incident.Id == 0 {
-		req, err = http.NewRequest("POST", apiUrl + "/incidents", bytes.NewBuffer(jsonBytes))
+		req, err = http.NewRequest("POST", Config.API_Url + "/incidents", bytes.NewBuffer(jsonBytes))
 	} else {
-		req, err = http.NewRequest("PUT", apiUrl + "/incidents/" + strconv.Itoa(incident.Id), bytes.NewBuffer(jsonBytes))
+		req, err = http.NewRequest("PUT", Config.API_Url + "/incidents/" + strconv.Itoa(incident.Id), bytes.NewBuffer(jsonBytes))
 	}
 
 	if err != nil {
@@ -43,7 +43,7 @@ func (incident *Incident) Send() {
 	}
 
 	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("X-Cachet-Token", apiToken)
+	req.Header.Set("X-Cachet-Token", Config.API_Token)
 
 	client := &http.Client{}
 	resp, err := client.Do(req)

cachet/metrics.go

@@ -5,38 +5,33 @@ import (
 	"bytes"
 	"strconv"
 	"net/http"
-	"io/ioutil"
 	"encoding/json"
 )
 
 func SendMetric(metricId int, delay int64) {
-	jsonBytes, err := json.Marshal(&map[string]interface{}{
+	if metricId <= 0 {
+		return
+	}
+
+	jsonBytes, _ := json.Marshal(&map[string]interface{}{
 		"value": delay,
 	})
-	if err != nil {
-		panic(err)
-	}
-
-	req, err := http.NewRequest("POST", apiUrl + "/metrics/" + strconv.Itoa(metricId) + "/points", bytes.NewBuffer(jsonBytes))
-	if err != nil {
-		panic(err)
-	}
-
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("X-Cachet-Token", apiToken)
 
 	client := &http.Client{}
+	req, _ := http.NewRequest("POST", Config.API_Url + "/metrics/" + strconv.Itoa(metricId) + "/points", bytes.NewBuffer(jsonBytes))
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("X-Cachet-Token", Config.API_Token)
+
 	resp, err := client.Do(req)
 	if err != nil {
-		panic(err)
+		fmt.Printf("Could not log data point!\n%v\n", err)
+		return
 	}
 
 	defer resp.Body.Close()
 
-	_, _ = ioutil.ReadAll(resp.Body)
-	// fmt.Println(strconv.Itoa(resp.StatusCode) + " " + string(body))
-
 	if resp.StatusCode != 200 {
 		fmt.Println("Could not log data point!")
 	}
-}
+}

cachet/monitor.go

@@ -17,6 +17,7 @@ type Monitor struct {
 	ExpectedStatusCode int `json:"expected_status_code"`
 
 	History []bool `json:"-"`
+	LastFailReason *string `json:"-"`
 	Incident *Incident `json:"-"`
 }
 
@@ -42,6 +43,8 @@ func (monitor *Monitor) doRequest() bool {
 	}
 	resp, err := client.Get(monitor.Url)
 	if err != nil {
+		errString := err.Error()
+		monitor.LastFailReason = &errString
 		return false
 	}
 
@@ -73,7 +76,11 @@ func (monitor *Monitor) AnalyseData() {
 
 		monitor.Incident = &Incident{
 			Name: monitor.Name,
-			Message: monitor.Name + " is unreachable.",
+			Message: monitor.Name + " failed",
+		}
+
+		if monitor.LastFailReason != nil {
+			monitor.Incident.Message += "\n\n" + *monitor.LastFailReason
 		}
 
 		monitor.Incident.SetInvestigating()
@@ -91,4 +98,4 @@ func (monitor *Monitor) AnalyseData() {
 
 func getMs() int64 {
 	return time.Now().UnixNano() / int64(time.Millisecond)
-}
+}

example.config.json

@@ -0,0 +1,14 @@
+{
+  "api_url": "https://demo.cachethq.io/api",
+  "api_token": "9yMHsdioQosnyVK4iCVR",
+  "monitors": [
+    {
+      "name": "nodegear frontend",
+      "url": "https://nodegear.io/ping",
+      "metric_id": 1,
+      "threshold": 80,
+      "component_id": null,
+      "expected_status_code": 200
+    }
+  ]
+}

main.go

@@ -7,24 +7,9 @@ import (
 )
 
 func main() {
-	monitors := []*cachet.Monitor{
+	fmt.Printf("API: %s\n", cachet.Config.API_Url)
-		/*&cachet.Monitor{
+	fmt.Printf("Starting %d monitors:\n", len(cachet.Config.Monitors))
-			Name: "nodegear frontend",
+	for _, monitor := range cachet.Config.Monitors {
-			Url: "https://nodegear.io/ping",
-			MetricId: 1,
-			Threshold: 80.0,
-			ExpectedStatusCode: 200,
-		},*/
-		&cachet.Monitor{
-			Name: "local test server",
-			Url: "http://localhost:1337",
-			Threshold: 80.0,
-			ExpectedStatusCode: 200,
-		},
-	}
-
-	fmt.Printf("Starting %d monitors:\n", len(monitors))
-	for _, monitor := range monitors {
 		fmt.Printf(" %s: GET %s & Expect HTTP %d\n", monitor.Name, monitor.Url, monitor.ExpectedStatusCode)
 		if monitor.MetricId > 0 {
 			fmt.Printf(" - Logs lag to metric id: %d\n", monitor.MetricId)
@@ -35,8 +20,8 @@ func main() {
 
 	ticker := time.NewTicker(time.Second)
 	for _ = range ticker.C {
-		for _, monitor := range monitors {
+		for _, monitor := range cachet.Config.Monitors {
 			go monitor.Run()
 		}
 	}
-}
+}

readme.md

@@ -6,9 +6,16 @@ This is a monitoring plugin for CachetHQ.
 How to run:
 -----------
 
+Example:
+
 1. Set up [Go](https://golang.org)
 2. `go install github.com/castawaylabs/cachet-monitor`
-3. `cachet-monitor`
+3. `cachet-monitor -c https://raw.githubusercontent.com/CastawayLabs/cachet-monitor/master/example.config.json`
+
+Production:
+
+1. Download the example config and save to `/etc/cachet-monitor.config.json`
+2. Run in background: `nohup cachet-monitor 2>&1 > /var/log/cachet-monitor.log &`
 
 Environment variables:
 ----------------------