Initial QSfera import

Server/services/thumbnails/pkg/thumbnail/imgsource/webdav.go

@@ -0,0 +1,75 @@
+package imgsource
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	_ "image/gif"  // Import the gif package so that image.Decode can understand gifs
+	_ "image/jpeg" // Import the jpeg package so that image.Decode can understand jpegs
+	_ "image/png"  // Import the png package so that image.Decode can understand pngs
+	"io"
+	"net/http"
+	"strconv"
+
+	"github.com/qsfera/server/services/thumbnails/pkg/config"
+	thumbnailerErrors "github.com/qsfera/server/services/thumbnails/pkg/errors"
+	"github.com/opencloud-eu/reva/v2/pkg/bytesize"
+	"github.com/pkg/errors"
+)
+
+// NewWebDavSource creates a new webdav instance.
+func NewWebDavSource(cfg config.Thumbnail, b bytesize.ByteSize) WebDav {
+	return WebDav{
+		insecure:         cfg.WebdavAllowInsecure,
+		maxImageFileSize: b.Bytes(),
+	}
+}
+
+// WebDav implements the Source interface for webdav services
+type WebDav struct {
+	insecure         bool
+	maxImageFileSize uint64
+}
+
+// Get downloads the file from a webdav service
+// The caller MUST make sure to close the returned ReadCloser
+func (s WebDav) Get(ctx context.Context, url string) (io.ReadCloser, error) {
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return nil, errors.Wrapf(err, `could not get the image "%s"`, url)
+	}
+
+	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{
+		MinVersion:         tls.VersionTLS12,
+		InsecureSkipVerify: s.insecure, //nolint:gosec
+	}
+
+	if auth, ok := ContextGetAuthorization(ctx); ok {
+		req.Header.Add("Authorization", auth)
+	}
+
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, errors.Wrapf(err, `could not get the image "%s"`, url)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("could not get the image \"%s\". Request returned with statuscode %d ", url, resp.StatusCode)
+	}
+
+	contentLength := resp.Header.Get("Content-Length")
+	if contentLength == "" {
+		// no size information - let's assume it is too big
+		return nil, thumbnailerErrors.ErrImageTooLarge
+	}
+	c, err := strconv.ParseUint(contentLength, 10, 64)
+	if err != nil {
+		return nil, errors.Wrapf(err, `could not parse content length of webdav response "%s"`, url)
+	}
+	if c > s.maxImageFileSize {
+		return nil, thumbnailerErrors.ErrImageTooLarge
+	}
+
+	return resp.Body, nil
+}