refactor thumbnails

Signed-off-by: Christian Richter <crichter@owncloud.com>

extensions/thumbnails/pkg/thumbnail/imgsource/cs3.go

@@ -0,0 +1,106 @@
+package imgsource
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+
+	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"
+	revactx "github.com/cs3org/reva/v2/pkg/ctx"
+	"github.com/cs3org/reva/v2/pkg/rhttp"
+	"github.com/owncloud/ocis/extensions/thumbnails/pkg/config"
+	"github.com/pkg/errors"
+	"google.golang.org/grpc/metadata"
+)
+
+const (
+	// "github.com/cs3org/reva/v2/internal/http/services/datagateway" is internal so we redeclare it here
+	// TokenTransportHeader holds the header key for the reva transfer token
+	TokenTransportHeader = "X-Reva-Transfer"
+)
+
+type CS3 struct {
+	client   gateway.GatewayAPIClient
+	insecure bool
+}
+
+func NewCS3Source(cfg config.Thumbnail, c gateway.GatewayAPIClient) CS3 {
+	return CS3{
+		client:   c,
+		insecure: cfg.CS3AllowInsecure,
+	}
+}
+
+// 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.New("cs3source: authorization missing")
+	}
+	var ref *provider.Reference
+	if strings.Contains(path, "!") {
+		parts := strings.Split(path, "!")
+		spaceID, path := parts[0], parts[1]
+		ref = &provider.Reference{
+			ResourceId: &provider.ResourceId{
+				StorageId: spaceID,
+				OpaqueId:  spaceID,
+			},
+			// Spaces requests need relative paths.
+			Path: "." + path,
+		}
+	} else {
+		ref = &provider.Reference{
+			Path: path,
+		}
+	}
+	ctx = metadata.AppendToOutgoingContext(context.Background(), revactx.TokenHeader, auth)
+	rsp, err := s.client.InitiateFileDownload(ctx, &provider.InitiateFileDownloadRequest{Ref: ref})
+
+	if err != nil {
+		return nil, err
+	}
+
+	if rsp.Status.Code != rpc.Code_CODE_OK {
+		return nil, fmt.Errorf("could not load image: %s", rsp.Status.Message)
+	}
+	var ep, tk string
+	for _, p := range rsp.Protocols {
+		if p.Protocol == "spaces" {
+			ep, tk = p.DownloadEndpoint, p.Token
+			break
+		}
+	}
+	if (ep == "" || tk == "") && len(rsp.Protocols) > 0 {
+		ep, tk = rsp.Protocols[0].DownloadEndpoint, rsp.Protocols[0].Token
+	}
+
+	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{
+		InsecureSkipVerify: s.insecure, //nolint:gosec
+	}
+	client := &http.Client{}
+
+	resp, err := client.Do(httpReq) // nolint:bodyclose
+	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
+}

extensions/thumbnails/pkg/thumbnail/imgsource/filesystem.go

@@ -0,0 +1,34 @@
+package imgsource
+
+import (
+	"context"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/owncloud/ocis/extensions/thumbnails/pkg/config"
+	"github.com/pkg/errors"
+)
+
+// NewFileSystemSource return a new FileSystem instance
+func NewFileSystemSource(cfg config.FileSystemSource) FileSystem {
+	return FileSystem{
+		basePath: cfg.BasePath,
+	}
+}
+
+// FileSystem is an image source using the local file system
+type FileSystem struct {
+	basePath string
+}
+
+// Get retrieves an image from the filesystem.
+func (s FileSystem) Get(ctx context.Context, file string) (io.ReadCloser, error) {
+	imgPath := filepath.Join(s.basePath, file)
+	f, err := os.Open(filepath.Clean(imgPath))
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to load the file %s from %s", file, imgPath)
+	}
+
+	return f, nil
+}

extensions/thumbnails/pkg/thumbnail/imgsource/imgsource.go

@@ -0,0 +1,31 @@
+package imgsource
+
+import (
+	"context"
+	"io"
+)
+
+type key int
+
+const (
+	auth key = iota
+)
+
+// Source defines the interface for image sources
+type Source interface {
+	Get(ctx context.Context, path string) (io.ReadCloser, error)
+}
+
+// ContextSetAuthorization puts the authorization in the context.
+func ContextSetAuthorization(parent context.Context, authorization string) context.Context {
+	return context.WithValue(parent, auth, authorization)
+}
+
+// ContextGetAuthorization gets the authorization from the context.
+func ContextGetAuthorization(ctx context.Context) (string, bool) {
+	val := ctx.Value(auth)
+	if val == nil {
+		return "", false
+	}
+	return val.(string), true
+}

extensions/thumbnails/pkg/thumbnail/imgsource/webdav.go

@@ -0,0 +1,54 @@
+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"
+
+	"github.com/owncloud/ocis/extensions/thumbnails/pkg/config"
+	"github.com/pkg/errors"
+)
+
+// NewWebDavSource creates a new webdav instance.
+func NewWebDavSource(cfg config.Thumbnail) WebDav {
+	return WebDav{
+		insecure: cfg.WebdavAllowInsecure,
+	}
+}
+
+// WebDav implements the Source interface for webdav services
+type WebDav struct {
+	insecure bool
+}
+
+// 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{InsecureSkipVerify: s.insecure} //nolint:gosec
+
+	if auth, ok := ContextGetAuthorization(ctx); ok {
+		req.Header.Add("Authorization", auth)
+	}
+
+	client := &http.Client{}
+	resp, err := client.Do(req) // nolint:bodyclose
+	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)
+	}
+
+	return resp.Body, nil
+}