add -dev flag and pass it to report and badge handlers. only badge handler needs it for now. add new make target for starting in dev mode

Makefile

@@ -16,5 +16,8 @@ test:
 start:
 	 go run main.go
 
+start-dev:
+	 go run main.go -dev
+
 misspell:
 	find . -name '*.go' | xargs misspell -error

handlers/badge.go

@@ -43,12 +43,15 @@ func grade(percentage float64) Grade {
 	}
 }
 
-func badgeURL(grade Grade, style string) string {
+func badgeURL(grade Grade, style string, dev bool) string {
+	if dev {
+		return fmt.Sprintf("http://localhost:8000/assets/badges/%s_%s.svg", strings.ToLower(string(grade)), strings.ToLower(style))
+	}
 	return fmt.Sprintf("https://goreportcard.com/assets/badges/%s_%s.svg", strings.ToLower(string(grade)), strings.ToLower(style))
 }
 
 // BadgeHandler handles fetching the badge images
-func BadgeHandler(w http.ResponseWriter, r *http.Request, repo string) {
+func BadgeHandler(w http.ResponseWriter, r *http.Request, repo string, dev bool) {
 	name := fmt.Sprintf("%s", repo)
 	resp, err := newChecksResp(name, false)
 
@@ -65,5 +68,5 @@ func BadgeHandler(w http.ResponseWriter, r *http.Request, repo string) {
 		return
 	}
 
-	http.Redirect(w, r, badgeURL(resp.Grade, style), http.StatusTemporaryRedirect)
+	http.Redirect(w, r, badgeURL(resp.Grade, style, dev), http.StatusTemporaryRedirect)
 }

handlers/report.go

@@ -13,7 +13,7 @@ var domain = flag.String("domain", "goreportcard.com", "Domain used for your gor
 var googleAnalyticsKey = flag.String("google_analytics_key", "UA-58936835-1", "Google Analytics Account Id")
 
 // ReportHandler handles the report page
-func ReportHandler(w http.ResponseWriter, r *http.Request, repo string) {
+func ReportHandler(w http.ResponseWriter, r *http.Request, repo string, dev bool) {
 	log.Printf("Displaying report: %q", repo)
 	t := template.Must(template.New("report.html").Delims("[[", "]]").ParseFiles("templates/report.html"))
 	resp, err := getFromCache(repo)

main.go

@@ -14,9 +14,12 @@ import (
 	"github.com/boltdb/bolt"
 )
 
-var addr = flag.String("http", ":8000", "HTTP listen address")
+var (
+	addr = flag.String("http", ":8000", "HTTP listen address")
+	dev  = flag.Bool("dev", false, "dev mode")
+)
 
-func makeHandler(name string, fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
+func makeHandler(name string, dev bool, fn func(http.ResponseWriter, *http.Request, string, bool)) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		validPath := regexp.MustCompile(fmt.Sprintf(`^/%s/([a-zA-Z0-9\-_\/\.]+)$`, name))
 
@@ -49,7 +52,7 @@ func makeHandler(name string, fn func(http.ResponseWriter, *http.Request, string
 			return
 		}
 
-		fn(w, r, repo)
+		fn(w, r, repo, dev)
 	}
 }
 
@@ -87,8 +90,8 @@ func main() {
 	http.HandleFunc("/assets/", handlers.AssetsHandler)
 	http.HandleFunc("/favicon.ico", handlers.FaviconHandler)
 	http.HandleFunc("/checks", handlers.CheckHandler)
-	http.HandleFunc("/report/", makeHandler("report", handlers.ReportHandler))
-	http.HandleFunc("/badge/", makeHandler("badge", handlers.BadgeHandler))
+	http.HandleFunc("/report/", makeHandler("report", *dev, handlers.ReportHandler))
+	http.HandleFunc("/badge/", makeHandler("badge", *dev, handlers.BadgeHandler))
 	http.HandleFunc("/high_scores/", handlers.HighScoresHandler)
 	http.HandleFunc("/about/", handlers.AboutHandler)
 	http.HandleFunc("/", handlers.HomeHandler)