GOLINT: Reduced complexity of main function

main.go

@@ -2,12 +2,10 @@ package main
 
 import (
 	"crypto/md5"
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
 	"os"
-	"sort"
 	"time"
 
 	"log"
@@ -41,136 +39,14 @@ func main() {
 	m.Use(martini.Static("assets", martini.StaticOptions{Prefix: "/assets"}))
 
 	// Real handlers
-	m.Get("/", func(res http.ResponseWriter, req *http.Request) {
+	m.Get("/", handleRedirectWelcome)
-		http.Redirect(res, req, "/welcome", 302)
+	m.Get("/create", handleCreateRandomDashboard)
-	})
+	m.Get("/:dashid", handleDisplayDashboard)
 
-	m.Get("/create", func(res http.ResponseWriter, req *http.Request) {
+	m.Put("/:dashid/:metricid", handlePutMetric)
-		urlProposal := generateAPIKey()[0:20]
-		_, err := s3Storage.Get(urlProposal)
-		for err == nil {
-			urlProposal = generateAPIKey()[0:20]
-			_, err = s3Storage.Get(urlProposal)
-		}
-		http.Redirect(res, req, fmt.Sprintf("/%s", urlProposal), http.StatusTemporaryRedirect)
-	})
 
-	m.Get("/:dashid", func(params martini.Params, res http.ResponseWriter) {
+	m.Delete("/:dashid", handleDeleteDashboard)
-		dash, err := loadDashboard(params["dashid"])
+	m.Delete("/:dashid/:metricid", handleDeleteMetric)
-		if err != nil {
-			dash = &dashboard{APIKey: generateAPIKey(), Metrics: dashboardMetrics{}}
-		}
-
-		// Filter out expired metrics
-		metrics := dashboardMetrics{}
-		for _, m := range dash.Metrics {
-			if m.Meta.LastUpdate.After(time.Now().Add(time.Duration(m.Expires*-1) * time.Second)) {
-				metrics = append(metrics, m)
-			}
-		}
-
-		sort.Sort(sort.Reverse(dashboardMetrics(metrics)))
-		renderTemplate("dashboard.html", pongo2.Context{
-			"dashid":  params["dashid"],
-			"metrics": metrics,
-			"apikey":  dash.APIKey,
-			"baseurl": os.Getenv("BASE_URL"),
-		}, res)
-	})
-
-	m.Delete("/:dashid", func(params martini.Params, req *http.Request, res http.ResponseWriter) {
-		dash, err := loadDashboard(params["dashid"])
-		if err != nil {
-			http.Error(res, "This dashboard does not exist.", http.StatusInternalServerError)
-			return
-		}
-
-		if dash.APIKey != req.Header.Get("Authorization") {
-			http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
-			return
-		}
-
-		_ = s3Storage.Del(params["dashid"])
-		http.Error(res, "OK", http.StatusOK)
-	})
-
-	m.Put("/:dashid/:metricid", func(params martini.Params, req *http.Request, res http.ResponseWriter) {
-		body, err := ioutil.ReadAll(req.Body)
-		if err != nil {
-			http.Error(res, "Internal Server Error", http.StatusInternalServerError)
-			return
-		}
-
-		metricUpdate := newDashboardMetric()
-		err = json.Unmarshal(body, metricUpdate)
-		if err != nil {
-			http.Error(res, "Unable to unmarshal json", http.StatusInternalServerError)
-			return
-		}
-
-		dash, err := loadDashboard(params["dashid"])
-		if err != nil {
-			if len(req.Header.Get("Authorization")) < 10 {
-				http.Error(res, "APIKey is too insecure", http.StatusUnauthorized)
-				return
-			}
-			dash = &dashboard{APIKey: req.Header.Get("Authorization"), Metrics: dashboardMetrics{}, DashboardID: params["dashid"]}
-		}
-
-		if dash.APIKey != req.Header.Get("Authorization") {
-			http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
-			return
-		}
-
-		valid, reason := metricUpdate.IsValid()
-		if !valid {
-			http.Error(res, fmt.Sprintf("Invalid data: %s", reason), http.StatusInternalServerError)
-			return
-		}
-
-		updated := false
-		for _, m := range dash.Metrics {
-			if m.MetricID == params["metricid"] {
-				m.Update(metricUpdate)
-				updated = true
-				break
-			}
-		}
-
-		if !updated {
-			tmp := newDashboardMetric()
-			tmp.MetricID = params["metricid"]
-			tmp.Update(metricUpdate)
-			dash.Metrics = append(dash.Metrics, tmp)
-		}
-
-		dash.Save()
-
-		http.Error(res, "OK", http.StatusOK)
-	})
-
-	m.Delete("/:dashid/:metricid", func(params martini.Params, req *http.Request, res http.ResponseWriter) {
-		dash, err := loadDashboard(params["dashid"])
-		if err != nil {
-			dash = &dashboard{APIKey: req.Header.Get("Authorization"), Metrics: dashboardMetrics{}, DashboardID: params["dashid"]}
-		}
-
-		if dash.APIKey != req.Header.Get("Authorization") {
-			http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
-			return
-		}
-
-		tmp := dashboardMetrics{}
-		for _, m := range dash.Metrics {
-			if m.MetricID != params["metricid"] {
-				tmp = append(tmp, m)
-			}
-		}
-		dash.Metrics = tmp
-		dash.Save()
-
-		http.Error(res, "OK", http.StatusOK)
-	})
 
 	go runWelcomePage()
 

web_handlers.go

@@ -0,0 +1,145 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"sort"
+	"time"
+
+	"github.com/flosch/pongo2"
+	"github.com/go-martini/martini"
+)
+
+func handleRedirectWelcome(res http.ResponseWriter, req *http.Request) {
+	http.Redirect(res, req, "/welcome", 302)
+}
+
+func handleCreateRandomDashboard(res http.ResponseWriter, req *http.Request) {
+	urlProposal := generateAPIKey()[0:20]
+	_, err := s3Storage.Get(urlProposal)
+	for err == nil {
+		urlProposal = generateAPIKey()[0:20]
+		_, err = s3Storage.Get(urlProposal)
+	}
+	http.Redirect(res, req, fmt.Sprintf("/%s", urlProposal), http.StatusTemporaryRedirect)
+}
+
+func handleDisplayDashboard(params martini.Params, res http.ResponseWriter) {
+	dash, err := loadDashboard(params["dashid"])
+	if err != nil {
+		dash = &dashboard{APIKey: generateAPIKey(), Metrics: dashboardMetrics{}}
+	}
+
+	// Filter out expired metrics
+	metrics := dashboardMetrics{}
+	for _, m := range dash.Metrics {
+		if m.Meta.LastUpdate.After(time.Now().Add(time.Duration(m.Expires*-1) * time.Second)) {
+			metrics = append(metrics, m)
+		}
+	}
+
+	sort.Sort(sort.Reverse(dashboardMetrics(metrics)))
+	renderTemplate("dashboard.html", pongo2.Context{
+		"dashid":  params["dashid"],
+		"metrics": metrics,
+		"apikey":  dash.APIKey,
+		"baseurl": os.Getenv("BASE_URL"),
+	}, res)
+}
+
+func handleDeleteDashboard(params martini.Params, req *http.Request, res http.ResponseWriter) {
+	dash, err := loadDashboard(params["dashid"])
+	if err != nil {
+		http.Error(res, "This dashboard does not exist.", http.StatusInternalServerError)
+		return
+	}
+
+	if dash.APIKey != req.Header.Get("Authorization") {
+		http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
+		return
+	}
+
+	_ = s3Storage.Del(params["dashid"])
+	http.Error(res, "OK", http.StatusOK)
+}
+
+func handlePutMetric(params martini.Params, req *http.Request, res http.ResponseWriter) {
+	body, err := ioutil.ReadAll(req.Body)
+	if err != nil {
+		http.Error(res, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	metricUpdate := newDashboardMetric()
+	err = json.Unmarshal(body, metricUpdate)
+	if err != nil {
+		http.Error(res, "Unable to unmarshal json", http.StatusInternalServerError)
+		return
+	}
+
+	dash, err := loadDashboard(params["dashid"])
+	if err != nil {
+		if len(req.Header.Get("Authorization")) < 10 {
+			http.Error(res, "APIKey is too insecure", http.StatusUnauthorized)
+			return
+		}
+		dash = &dashboard{APIKey: req.Header.Get("Authorization"), Metrics: dashboardMetrics{}, DashboardID: params["dashid"]}
+	}
+
+	if dash.APIKey != req.Header.Get("Authorization") {
+		http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
+		return
+	}
+
+	valid, reason := metricUpdate.IsValid()
+	if !valid {
+		http.Error(res, fmt.Sprintf("Invalid data: %s", reason), http.StatusInternalServerError)
+		return
+	}
+
+	updated := false
+	for _, m := range dash.Metrics {
+		if m.MetricID == params["metricid"] {
+			m.Update(metricUpdate)
+			updated = true
+			break
+		}
+	}
+
+	if !updated {
+		tmp := newDashboardMetric()
+		tmp.MetricID = params["metricid"]
+		tmp.Update(metricUpdate)
+		dash.Metrics = append(dash.Metrics, tmp)
+	}
+
+	dash.Save()
+
+	http.Error(res, "OK", http.StatusOK)
+}
+
+func handleDeleteMetric(params martini.Params, req *http.Request, res http.ResponseWriter) {
+	dash, err := loadDashboard(params["dashid"])
+	if err != nil {
+		dash = &dashboard{APIKey: req.Header.Get("Authorization"), Metrics: dashboardMetrics{}, DashboardID: params["dashid"]}
+	}
+
+	if dash.APIKey != req.Header.Get("Authorization") {
+		http.Error(res, "APIKey did not match.", http.StatusUnauthorized)
+		return
+	}
+
+	tmp := dashboardMetrics{}
+	for _, m := range dash.Metrics {
+		if m.MetricID != params["metricid"] {
+			tmp = append(tmp, m)
+		}
+	}
+	dash.Metrics = tmp
+	dash.Save()
+
+	http.Error(res, "OK", http.StatusOK)
+}