Split into service and main, refactor some code and add better tests

.drone.yml

@@ -0,0 +1,9 @@
+kind: pipeline
+type: docker
+name: default
+
+steps:
+  - name: test
+    image: golang
+    commands:
+      - go test

default.go

@@ -1,4 +1,4 @@
-package main
+package linkinfo
 
 import (
 	"errors"
@@ -29,7 +29,7 @@ func defaultLinkHandler(link string) (*LinkInfo, error) {
 	var res *http.Response
 
 	for i := 0; i < 10; i++ {
-		res, err = client.Head(link)
+		res, err = Client.Head(link)
 
 		if err != nil {
 			return nil, err
@@ -64,7 +64,7 @@ func defaultLinkHandler(link string) (*LinkInfo, error) {
 	}
 
 	ret := &LinkInfo{
-		ContentType: contentType,
+		ContentType:   contentType,
 		ContentLength: contentLength,
 	}
 
@@ -87,7 +87,7 @@ func detectContentType(link, defaultType string) string {
 
 	req.Header.Set("Range", "bytes=0-512")
 
-	res, err := client.Do(req)
+	res, err := Client.Do(req)
 
 	if err != nil {
 		return defaultType
@@ -115,7 +115,7 @@ var (
 )
 
 func retrieveHtmlLinkTitle(i *LinkInfo, link string) error {
-	res, err := client.Get(link)
+	res, err := Client.Get(link)
 
 	if err != nil {
 		return err
@@ -170,4 +170,4 @@ func retrieveHtmlLinkTitle(i *LinkInfo, link string) error {
 	}
 
 	return nil
-}
+}

default_test.go

@@ -1,20 +1,31 @@
-package main
+package linkinfo
 
 import (
-	"net/http"
+	"strings"
 	"testing"
-	"time"
 )
 
-func Test_DefaultLinkHandler(t *testing.T) {
-	client = &http.Client{
-		Timeout: 10 * time.Second,
+func Test_detectContentType(t *testing.T) {
+	contentType := detectContentType("http://example.com", "")
+
+	if contentType == "" {
+		t.Fatal("Unable to test example.com, returned empty type")
+	}
+
+	if idx := strings.Index(contentType, ";"); idx != -1 {
+		contentType = contentType[:idx]
+	}
+
+	if contentType != ContentTypeHtml {
+		t.Fatal("Unexpected content type:", contentType)
 	}
+}
 
+func Test_defaultLinkHandler(t *testing.T) {
 	type expectedData struct {
-		Link string
+		Link  string
 		Title string
-		Type string
+		Type  string
 	}
 
 	testLinks := []expectedData{
@@ -37,4 +48,4 @@ func Test_DefaultLinkHandler(t *testing.T) {
 			t.Fatal("Unexpected content type, expected:", link.Type, "got:", l.ContentType)
 		}
 	}
-}
+}

linkinfo.go

@@ -0,0 +1,46 @@
+package linkinfo
+
+import (
+	"net/http"
+	"net/url"
+)
+
+type linkHandler struct {
+	hosts   []string
+	handler func(link string) (*LinkInfo, error)
+}
+
+type LinkInfo struct {
+	Title         string   `json:"title"`
+	Description   string   `json:"description"`
+	ContentType   string   `json:"type"`
+	ContentLength int64    `json:"contentLength"`
+	Duration      string   `json:"duration,omitempty"`
+	Redirects     []string `json:"redirects,omitempty"`
+}
+
+var (
+	Client = http.DefaultClient
+
+	linkHandlers = []*linkHandler{
+		{hosts: []string{"youtube.com", "youtu.be"}, handler: youtubeLinkHandler},
+	}
+)
+
+func Retrieve(link string) (*LinkInfo, error) {
+	u, err := url.Parse(link)
+
+	if err != nil {
+		return nil, err
+	}
+
+	for _, handler := range linkHandlers {
+		for _, host := range handler.hosts {
+			if host == u.Hostname() {
+				return handler.handler(link)
+			}
+		}
+	}
+
+	return defaultLinkHandler(link)
+}

main.go

@@ -1,33 +0,0 @@
-package main
-
-import (
-	"net/http"
-	"time"
-)
-
-var (
-	client *http.Client
-)
-
-type LinkInfo struct {
-	Title string `json:"title"`
-	Description string `json:"description"`
-	ContentType string `json:"type"`
-	ContentLength int64 `json:"contentLength"`
-	Duration string `json:"duration,omitempty"`
-	Redirects []string `json:"redirects,omitempty"`
-}
-
-func main() {
-	client = &http.Client{
-		Timeout: 10 * time.Second,
-	}
-
-	mux := http.NewServeMux()
-	mux.HandleFunc("/info", handleInfoRequest)
-	http.ListenAndServe(":8080", mux)
-}
-
-func handleInfoRequest(w http.ResponseWriter, r *http.Request) {
-
-}

service/main.go

@@ -0,0 +1,15 @@
+package main
+
+import (
+	"net/http"
+)
+
+func main() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/info", handleInfoRequest)
+	http.ListenAndServe(":8080", mux)
+}
+
+func handleInfoRequest(w http.ResponseWriter, r *http.Request) {
+
+}

util.go

@@ -1,4 +1,4 @@
-package main
+package linkinfo
 
 import "fmt"
 

youtube.go

@@ -0,0 +1,5 @@
+package linkinfo
+
+func youtubeLinkHandler(link string) (*LinkInfo, error) {
+	return nil, nil
+}