Added useful comments

src/viddown.go

@@ -46,18 +46,25 @@ const template = `
 </html>
 `
 
+// Used to request an operation (download)
 type ops struct {
 	URL string
 	Res chan string
 }
 
+// List of the operations currently being worked on
 var currentWork map[int]string
 
+// program configurations
 var config struct {
+	// Where files should be saved
 	saveLocation string
 }
+
+// Global channel to send operation requests to
 var opsc = make(chan ops)
 
+// handleRequest handles http requests
 func handleRequest(w http.ResponseWriter, r *http.Request) {
 	if r.Method == http.MethodGet {
 		log.Print("New Get request")
@@ -70,6 +77,8 @@ func handleRequest(w http.ResponseWriter, r *http.Request) {
 		}()
 	} else {
 	}
+
+	// Modify template and send it to the requester
 	var insert string
 	for _, url := range currentWork {
 		insert += "<br>" + url
@@ -81,22 +90,28 @@ func handleRequest(w http.ResponseWriter, r *http.Request) {
 func downloadVid(r *http.Request) {
 }
 
+// operationHandler waits for operation requests and initiates them
 func operationHandler() {
+	// Simple index for sorting video work
 	for i := 0; true; i++ {
 		o := <-opsc
 		log.Print("Start Downloading: " + o.URL)
+
+		// Spin off a go routine to handle a download so the handler can continue to receive requests
 		go func() {
+			// Create a unique directory to download the video in
 			dir := path.Join(config.saveLocation, ".viddown", strconv.Itoa(i))
 			os.MkdirAll(dir, 0755)
+
+			// Build the download command
 			cmd := exec.Command("youtube-dl", o.URL)
 			cmd.Dir = dir + "/"
-			currentWork[i] = o.URL
+			currentWork[i] = o.URL // Adds the URL to list of current work
 			cmd.Run()
-
 			log.Print("Finished: " + o.URL)
+			delete(currentWork, i) // Remove the URL from list of current work
 
-			delete(currentWork, i)
-
+			// Clean up directory
 			files, err := ioutil.ReadDir(dir + "/")
 			if err != nil {
 				log.Print(err)
@@ -122,6 +137,7 @@ func operationHandler() {
 }
 
 func main() {
+	// Set the location to save videos
 	if os.Getenv("VIDDOWNLOC") == "" {
 		config.saveLocation = "./"
 	} else {
@@ -129,12 +145,16 @@ func main() {
 	}
 	log.Println("Downloading files to: " + config.saveLocation)
 
+	// initialize currentWork with a blank map
 	currentWork = make(map[int]string)
 
+	// Create the work directory
 	os.MkdirAll(path.Join(config.saveLocation, ".viddown"), 0755)
 
+	// Start the operations handler
 	go operationHandler()
 
+	// Start the http server
 	handler := http.HandlerFunc(handleRequest)
 	http.Handle("/", handler)
 	log.Printf("Starting server on 8080")