Added error hadnling

util.go

@@ -13,12 +13,12 @@ import (
 
 var Debug = false
 
-func DoAssetsRequest(addonID, version string) AssetsReply {
+func DoAssetsRequest(addonID, version string) (AssetsReply, error) {
 	url := "https://api-ar-workshop.bistudio.com/workshop-api/api/v3.0/s2s/assets/download-list"
 	body := `{"assets":{"` + addonID + `":"` + version + `"}}`
 	req, err := http.NewRequest("POST", url, strings.NewReader(body))
 	if err != nil {
-		panic(err)
+		return AssetsReply{}, err
 	}
 
 	req.Header.Add("x-client-id", "$edb1b7862bba5cade1f6e06bfdeac2c")
@@ -29,7 +29,7 @@ func DoAssetsRequest(addonID, version string) AssetsReply {
 
 	res, err := http.DefaultClient.Do(req)
 	if err != nil {
-		panic(err)
+		return AssetsReply{}, err
 	}
 	defer res.Body.Close()
 
@@ -47,24 +47,24 @@ func DoAssetsRequest(addonID, version string) AssetsReply {
 		panic(err)
 	}
 
-	return assetsReply
+	return assetsReply, nil
 }
 
-func GetManifest(manifestUrl string) Manifest {
+func GetManifest(manifestUrl string) (Manifest, error) {
 	url := "https://ar-gcp-cdn.bistudio.com/manifest/" + manifestUrl
 	req, err := http.NewRequest("GET", url, nil)
 	if err != nil {
-		panic(err)
+		return Manifest{}, err
 	}
 
 	res, err := http.DefaultClient.Do(req)
 	if err != nil {
-		panic(err)
+		return Manifest{}, err
 	}
 	defer res.Body.Close()
 
 	if res.StatusCode != 200 {
-		panic("bad status: " + res.Status)
+		return Manifest{}, fmt.Errorf("bad status: %s", res.Status)
 	}
 
 	// Decode the JSON response
@@ -73,15 +73,15 @@ func GetManifest(manifestUrl string) Manifest {
 		panic(err)
 	}
 
-	return manifest
+	return manifest, nil
 }
 
-func Download(manifest Manifest, downloadDir string, filen string) []byte {
+func Download(manifest Manifest, downloadDir string, filen string) ([]byte, error) {
 
 	if Debug {
 		// create the directory if it doesn't exist
 		if err := os.MkdirAll(downloadDir + "/fragments/" + filen, os.ModePerm); err != nil {
-			panic(err)
+			return nil, err
 		}
 	}
 
@@ -91,14 +91,17 @@ func Download(manifest Manifest, downloadDir string, filen string) []byte {
 	currentRem := 0
 	if (manifest.Remainder.Size > 0) {
 		url := transformShaToURL(manifest.Remainder.Sha512, manifest.Remainder.Size)
-		content := getContent(url)
+		content, err := getContent(url)
+		if err != nil {
+			return nil, err
+		}
 		remContent = content
 		downloaded += len(content)
 		
 		if Debug {
 			// save remainder to file in the fragments/ directory, prefix with gap
 			if err := os.WriteFile(filepath.Join(downloadDir, "fragments", filen, fmt.Sprintf("%d.%s.%d.bytes", manifest.Remainder.Offsets[0], manifest.Remainder.Sha512, manifest.Remainder.Size)), remContent, os.ModePerm); err != nil {
-				panic(err)
+				return nil, err
 			}
 		}
 	}
@@ -110,7 +113,10 @@ func Download(manifest Manifest, downloadDir string, filen string) []byte {
 	ret := make([]byte, manifest.Size)
 	for _, fragment := range manifest.Fragments {
 		url := transformShaToURL(fragment.Sha512, fragment.Size)
-		content := getContent(url)
+		content, err := getContent(url)
+		if err != nil {
+			return nil, err
+		}
 		downloaded += len(content) * len(fragment.Offsets)
 		for _, offset := range fragment.Offsets {
 			trackFrag = append(trackFrag, Frag{Offset: offset, Size: len(content)})
@@ -120,7 +126,7 @@ func Download(manifest Manifest, downloadDir string, filen string) []byte {
 		if Debug {
 			// save fragment to file in the fragments/ directory
 			if err := os.WriteFile(filepath.Join(downloadDir, "fragments", filen, fmt.Sprintf("%d.%s.%d.bytes", fragment.Offsets[0], fragment.Sha512, fragment.Size)), content, os.ModePerm); err != nil {
-				panic(err)
+				return nil, err
 			}
 		}
 		
@@ -152,26 +158,26 @@ func Download(manifest Manifest, downloadDir string, filen string) []byte {
 	copy(ret[curPos:], remContent)
 	fmt.Println()
 
-	return ret
+	return ret, nil
 }
 
-func getContent(url string) []byte {
+func getContent(url string) ([]byte, error) {
 	resp, err := http.Get(url)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode != 200 {
-		panic("bad status: " + resp.Status)
+		return nil, fmt.Errorf("bad status: %s", resp.Status)
 	}
 
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
 
-	return body
+	return body, nil
 }
 
 func transformShaToURL(sha512s string, size int) string {