feat: initial commit

pkg/wails3kit/updates/downloader.go

@@ -0,0 +1,58 @@
+package updates
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+)
+
+type HTTPDownloader struct {
+	client *http.Client
+}
+
+func NewHTTPDownloader(client *http.Client) *HTTPDownloader {
+	if client == nil {
+		client = http.DefaultClient
+	}
+	return &HTTPDownloader{client: client}
+}
+
+func (downloader *HTTPDownloader) Download(ctx context.Context, artifact Artifact) (DownloadedFile, error) {
+	request, err := http.NewRequestWithContext(ctx, http.MethodGet, artifact.URL, nil)
+	if err != nil {
+		return DownloadedFile{}, err
+	}
+
+	response, err := downloader.client.Do(request)
+	if err != nil {
+		return DownloadedFile{}, err
+	}
+	defer response.Body.Close()
+
+	if response.StatusCode < 200 || response.StatusCode >= 300 {
+		return DownloadedFile{}, fmt.Errorf("unexpected download status: %s", response.Status)
+	}
+
+	file, err := os.CreateTemp("", "wails3kit-download-*")
+	if err != nil {
+		return DownloadedFile{}, err
+	}
+	defer file.Close()
+
+	hash := sha256.New()
+	written, err := io.Copy(io.MultiWriter(file, hash), response.Body)
+	if err != nil {
+		_ = os.Remove(file.Name())
+		return DownloadedFile{}, err
+	}
+
+	return DownloadedFile{
+		Path:   file.Name(),
+		Size:   written,
+		SHA256: hex.EncodeToString(hash.Sum(nil)),
+	}, nil
+}