Initial QSfera import

Server/services/thumbnails/pkg/thumbnail/imgsource/cs3.go

@@ -0,0 +1,132 @@
+package imgsource
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net/http"
+
+	gateway "github.com/cs3org/go-cs3apis/cs3/gateway/v1beta1"
+	rpc "github.com/cs3org/go-cs3apis/cs3/rpc/v1beta1"
+	provider "github.com/cs3org/go-cs3apis/cs3/storage/provider/v1beta1"
+	"github.com/qsfera/server/services/thumbnails/pkg/config"
+	"github.com/qsfera/server/services/thumbnails/pkg/errors"
+	"github.com/opencloud-eu/reva/v2/pkg/bytesize"
+	revactx "github.com/opencloud-eu/reva/v2/pkg/ctx"
+	"github.com/opencloud-eu/reva/v2/pkg/rgrpc/todo/pool"
+	"github.com/opencloud-eu/reva/v2/pkg/rhttp"
+	"github.com/opencloud-eu/reva/v2/pkg/storagespace"
+	"google.golang.org/grpc/metadata"
+)
+
+const (
+	// TokenTransportHeader holds the header key for the reva transfer token
+	// "github.com/opencloud-eu/reva/v2/internal/http/services/datagateway" is internal so we redeclare it here
+	TokenTransportHeader = "X-Reva-Transfer"
+)
+
+// CS3 implements a CS3 image source
+type CS3 struct {
+	gatewaySelector  pool.Selectable[gateway.GatewayAPIClient]
+	insecure         bool
+	maxImageFileSize uint64
+}
+
+// NewCS3Source configures a new CS3 image source
+func NewCS3Source(cfg config.Thumbnail, gatewaySelector pool.Selectable[gateway.GatewayAPIClient], b bytesize.ByteSize) CS3 {
+	return CS3{
+		gatewaySelector:  gatewaySelector,
+		insecure:         cfg.CS3AllowInsecure,
+		maxImageFileSize: b.Bytes(),
+	}
+}
+
+// Get downloads the file from a cs3 service
+// The caller MUST make sure to close the returned ReadCloser
+func (s CS3) Get(ctx context.Context, path string) (io.ReadCloser, error) {
+	auth, ok := ContextGetAuthorization(ctx)
+	if !ok {
+		return nil, errors.ErrCS3AuthorizationMissing
+	}
+	ref, err := storagespace.ParseReference(path)
+	if err != nil {
+		// If the path is not a spaces reference try to handle it like a plain
+		// path reference.
+		ref = provider.Reference{
+			Path: path,
+		}
+	}
+
+	ctx = metadata.AppendToOutgoingContext(context.Background(), revactx.TokenHeader, auth)
+	err = s.checkImageFileSize(ctx, ref)
+	if err != nil {
+		return nil, err
+	}
+
+	gwc, err := s.gatewaySelector.Next()
+	if err != nil {
+		return nil, err
+	}
+	rsp, err := gwc.InitiateFileDownload(ctx, &provider.InitiateFileDownloadRequest{Ref: &ref})
+
+	if err != nil {
+		return nil, err
+	}
+
+	if rsp.GetStatus().GetCode() != rpc.Code_CODE_OK {
+		return nil, fmt.Errorf("could not load image: %s", rsp.GetStatus().GetMessage())
+	}
+	var ep, tk string
+	for _, p := range rsp.GetProtocols() {
+		if p.GetProtocol() == "spaces" {
+			ep, tk = p.GetDownloadEndpoint(), p.GetToken()
+			break
+		}
+	}
+	if (ep == "" || tk == "") && len(rsp.GetProtocols()) > 0 {
+		ep, tk = rsp.GetProtocols()[0].GetDownloadEndpoint(), rsp.GetProtocols()[0].GetToken()
+	}
+
+	httpReq, err := rhttp.NewRequest(ctx, "GET", ep, nil)
+	if err != nil {
+		return nil, err
+	}
+	httpReq.Header.Set(revactx.TokenHeader, auth)
+	httpReq.Header.Set(TokenTransportHeader, tk)
+
+	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{
+		MinVersion:         tls.VersionTLS12,
+		InsecureSkipVerify: s.insecure, //nolint:gosec
+	}
+	client := &http.Client{}
+
+	resp, err := client.Do(httpReq)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("could not get the image \"%s\". Request returned with statuscode %d ", path, resp.StatusCode)
+	}
+
+	return resp.Body, nil
+}
+
+func (s CS3) checkImageFileSize(ctx context.Context, ref provider.Reference) error {
+	gwc, err := s.gatewaySelector.Next()
+	if err != nil {
+		return err
+	}
+	stat, err := gwc.Stat(ctx, &provider.StatRequest{Ref: &ref})
+	if err != nil {
+		return err
+	}
+	if stat.GetStatus().GetCode() != rpc.Code_CODE_OK {
+		return fmt.Errorf("could not stat image: %s", stat.GetStatus().GetMessage())
+	}
+	if stat.GetInfo().GetSize() > s.maxImageFileSize {
+		return errors.ErrImageTooLarge
+	}
+	return nil
+}