Sync and Async requests support added by using go keyword.

export.go

@@ -0,0 +1,20 @@
+package gezer
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+func Export(response *Response) {
+	file, err := os.Create("out.json")
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "output file creation error: %v", err)
+		return
+	}
+
+	for res := range response.Exports {
+		//fmt.Println(res)
+		_ = json.NewEncoder(file).Encode(res)
+	}
+}

gezer.go

@@ -2,7 +2,6 @@ package gezer
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"github.com/PuerkitoBio/goquery"
 	"io/ioutil"
@@ -35,40 +34,19 @@ func NewGezer(opt Opt) *Gezer {
 }
 
 func (g *Gezer) Start() {
-	g.wg.Add(len(g.opt.StartURLs))
-
-	for _, url := range g.opt.StartURLs {
-		go g.getRequest(url)
+	for _, startURL := range g.opt.StartURLs {
+		go g.Get(startURL)
 	}
 
+	time.Sleep(time.Millisecond)
 	g.wg.Wait()
 }
 
-func (g *Gezer) Get(url string) {
+func (g *Gezer) Get(rawURL string) {
 	g.wg.Add(1)
-	go g.getRequest(url)
-}
-
-func (g *Gezer) getRequest(rawURL string) {
 	defer g.wg.Done()
 
-	// Parse URL
-	parsedURL, err := url.Parse(rawURL)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "url parsing error: %v", err)
-		return
-	}
-
-	// Check for allowed domains
-	var allowed bool
-	for _, domain := range g.opt.AllowedDomains {
-		if domain == parsedURL.Host {
-			allowed = true
-			break
-		}
-	}
-	if !allowed && len(g.opt.AllowedDomains) != 0 {
-		fmt.Fprintf(os.Stderr, "domain not allowed: %s", parsedURL.Host)
+	if !checkURL(rawURL, g.opt.AllowedDomains) {
 		return
 	}
 
@@ -87,7 +65,7 @@ func (g *Gezer) getRequest(rawURL string) {
 	// Read body
 	body, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "reading body error: %v", err)
+		fmt.Fprintf(os.Stderr, "reading body error: %v\n", err)
 		return
 	}
 
@@ -104,21 +82,34 @@ func (g *Gezer) getRequest(rawURL string) {
 	}
 
 	// Export Function
-	go func() {
-		file, err := os.Create("out.json")
-		if err != nil {
-			fmt.Fprintf(os.Stderr, "output file creation error: %v", err)
-			return
-		}
-
-		for res := range response.Exports {
-			fmt.Println(res)
-			_ = json.NewEncoder(file).Encode(res)
-		}
-
-	}()
+	go Export(&response)
 
 	// ParseFunc response
 	g.opt.ParseFunc(&response)
-
+	time.Sleep(time.Millisecond)
+}
+
+func checkURL(rawURL string, allowedDomains []string) bool {
+
+	// Parse URL
+	parsedURL, err := url.Parse(rawURL)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "url parsing error: %v\n", err)
+		return false
+	}
+
+	// Check for allowed domains
+	var allowed bool
+	for _, domain := range allowedDomains {
+		if domain == parsedURL.Host {
+			allowed = true
+			break
+		}
+	}
+	if !allowed && len(allowedDomains) != 0 {
+		fmt.Fprintf(os.Stderr, "domain not allowed: %s\n", parsedURL.Host)
+		return false
+	}
+
+	return true
 }

gezer_test.go

@@ -30,9 +30,24 @@ func TestGezer_StartURLs_HTML(t *testing.T) {
 				}
 			})
 			if href, ok := r.Doc.Find("li.next > a").Attr("href"); ok {
-				r.Gezer.Get(r.JoinURL(href))
+				go r.Gezer.Get(r.JoinURL(href))
 			}
 		},
 	})
 	gezer.Start()
 }
+
+func TestGezer_Concurrent_Requests(t *testing.T) {
+	gezer := NewGezer(Opt{
+		AllowedDomains: []string{"quotes.toscrape.com"},
+		StartURLs:      []string{"http://quotes.toscrape.com/"},
+		ParseFunc: func(r *Response) {
+			r.Doc.Find("a").Each(func(i int, s *goquery.Selection) {
+				if href, ok := s.Attr("href"); ok {
+					go r.Gezer.Get(r.JoinURL(href))
+				}
+			})
+		},
+	})
+	gezer.Start()
+}