1 files changed, 269 insertions, 0 deletions
diff --git a/mediaapi/routing/upload.go b/mediaapi/routing/upload.go
new file mode 100644
index 00000000..1051e0e0
--- /dev/null
+++ b/mediaapi/routing/upload.go
@@ -0,0 +1,269 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package routing
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strings"
+
+	"github.com/matrix-org/dendrite/clientapi/jsonerror"
+	"github.com/matrix-org/dendrite/common/config"
+	"github.com/matrix-org/dendrite/mediaapi/fileutils"
+	"github.com/matrix-org/dendrite/mediaapi/storage"
+	"github.com/matrix-org/dendrite/mediaapi/thumbnailer"
+	"github.com/matrix-org/dendrite/mediaapi/types"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+	log "github.com/sirupsen/logrus"
+)
+
+// uploadRequest metadata included in or derivable from an upload request
+// https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-media-r0-upload
+// NOTE: The members come from HTTP request metadata such as headers, query parameters or can be derived from such
+type uploadRequest struct {
+	MediaMetadata *types.MediaMetadata
+	Logger        *log.Entry
+}
+
+// uploadResponse defines the format of the JSON response
+// https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-media-r0-upload
+type uploadResponse struct {
+	ContentURI string `json:"content_uri"`
+}
+
+// Upload implements /upload
+// This endpoint involves uploading potentially significant amounts of data to the homeserver.
+// This implementation supports a configurable maximum file size limit in bytes. If a user tries to upload more than this, they will receive an error that their upload is too large.
+// Uploaded files are processed piece-wise to avoid DoS attacks which would starve the server of memory.
+// TODO: We should time out requests if they have not received any data within a configured timeout period.
+func Upload(req *http.Request, cfg *config.Dendrite, db *storage.Database, activeThumbnailGeneration *types.ActiveThumbnailGeneration) util.JSONResponse {
+	r, resErr := parseAndValidateRequest(req, cfg)
+	if resErr != nil {
+		return *resErr
+	}
+
+	if resErr = r.doUpload(req.Context(), req.Body, cfg, db, activeThumbnailGeneration); resErr != nil {
+		return *resErr
+	}
+
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: uploadResponse{
+			ContentURI: fmt.Sprintf("mxc://%s/%s", cfg.Matrix.ServerName, r.MediaMetadata.MediaID),
+		},
+	}
+}
+
+// parseAndValidateRequest parses the incoming upload request to validate and extract
+// all the metadata about the media being uploaded.
+// Returns either an uploadRequest or an error formatted as a util.JSONResponse
+func parseAndValidateRequest(req *http.Request, cfg *config.Dendrite) (*uploadRequest, *util.JSONResponse) {
+	if req.Method != http.MethodPost {
+		return nil, &util.JSONResponse{
+			Code: http.StatusMethodNotAllowed,
+			JSON: jsonerror.Unknown("HTTP request method must be POST."),
+		}
+	}
+
+	r := &uploadRequest{
+		MediaMetadata: &types.MediaMetadata{
+			Origin:        cfg.Matrix.ServerName,
+			FileSizeBytes: types.FileSizeBytes(req.ContentLength),
+			ContentType:   types.ContentType(req.Header.Get("Content-Type")),
+			UploadName:    types.Filename(url.PathEscape(req.FormValue("filename"))),
+		},
+		Logger: util.GetLogger(req.Context()).WithField("Origin", cfg.Matrix.ServerName),
+	}
+
+	if resErr := r.Validate(*cfg.Media.MaxFileSizeBytes); resErr != nil {
+		return nil, resErr
+	}
+
+	return r, nil
+}
+
+func (r *uploadRequest) doUpload(
+	ctx context.Context,
+	reqReader io.Reader,
+	cfg *config.Dendrite,
+	db *storage.Database,
+	activeThumbnailGeneration *types.ActiveThumbnailGeneration,
+) *util.JSONResponse {
+	r.Logger.WithFields(log.Fields{
+		"UploadName":    r.MediaMetadata.UploadName,
+		"FileSizeBytes": r.MediaMetadata.FileSizeBytes,
+		"ContentType":   r.MediaMetadata.ContentType,
+	}).Info("Uploading file")
+
+	// The file data is hashed and the hash is used as the MediaID. The hash is useful as a
+	// method of deduplicating files to save storage, as well as a way to conduct
+	// integrity checks on the file data in the repository.
+	// Data is truncated to maxFileSizeBytes. Content-Length was reported as 0 < Content-Length <= maxFileSizeBytes so this is OK.
+	hash, bytesWritten, tmpDir, err := fileutils.WriteTempFile(reqReader, *cfg.Media.MaxFileSizeBytes, cfg.Media.AbsBasePath)
+	if err != nil {
+		r.Logger.WithError(err).WithFields(log.Fields{
+			"MaxFileSizeBytes": *cfg.Media.MaxFileSizeBytes,
+		}).Warn("Error while transferring file")
+		fileutils.RemoveDir(tmpDir, r.Logger)
+		return &util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.Unknown("Failed to upload"),
+		}
+	}
+
+	r.MediaMetadata.FileSizeBytes = bytesWritten
+	r.MediaMetadata.Base64Hash = hash
+	r.MediaMetadata.MediaID = types.MediaID(hash)
+
+	r.Logger = r.Logger.WithField("MediaID", r.MediaMetadata.MediaID)
+
+	r.Logger.WithFields(log.Fields{
+		"Base64Hash":    r.MediaMetadata.Base64Hash,
+		"UploadName":    r.MediaMetadata.UploadName,
+		"FileSizeBytes": r.MediaMetadata.FileSizeBytes,
+		"ContentType":   r.MediaMetadata.ContentType,
+	}).Info("File uploaded")
+
+	// check if we already have a record of the media in our database and if so, we can remove the temporary directory
+	mediaMetadata, err := db.GetMediaMetadata(
+		ctx, r.MediaMetadata.MediaID, r.MediaMetadata.Origin,
+	)
+	if err != nil {
+		r.Logger.WithError(err).Error("Error querying the database.")
+		resErr := jsonerror.InternalServerError()
+		return &resErr
+	}
+
+	if mediaMetadata != nil {
+		r.MediaMetadata = mediaMetadata
+		fileutils.RemoveDir(tmpDir, r.Logger)
+		return &util.JSONResponse{
+			Code: http.StatusOK,
+			JSON: uploadResponse{
+				ContentURI: fmt.Sprintf("mxc://%s/%s", cfg.Matrix.ServerName, r.MediaMetadata.MediaID),
+			},
+		}
+	}
+
+	return r.storeFileAndMetadata(
+		ctx, tmpDir, cfg.Media.AbsBasePath, db, cfg.Media.ThumbnailSizes,
+		activeThumbnailGeneration, cfg.Media.MaxThumbnailGenerators,
+	)
+}
+
+// Validate validates the uploadRequest fields
+func (r *uploadRequest) Validate(maxFileSizeBytes config.FileSizeBytes) *util.JSONResponse {
+	if r.MediaMetadata.FileSizeBytes < 1 {
+		return &util.JSONResponse{
+			Code: http.StatusLengthRequired,
+			JSON: jsonerror.Unknown("HTTP Content-Length request header must be greater than zero."),
+		}
+	}
+	if maxFileSizeBytes > 0 && r.MediaMetadata.FileSizeBytes > types.FileSizeBytes(maxFileSizeBytes) {
+		return &util.JSONResponse{
+			Code: http.StatusRequestEntityTooLarge,
+			JSON: jsonerror.Unknown(fmt.Sprintf("HTTP Content-Length is greater than the maximum allowed upload size (%v).", maxFileSizeBytes)),
+		}
+	}
+	// TODO: Check if the Content-Type is a valid type?
+	if r.MediaMetadata.ContentType == "" {
+		return &util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.Unknown("HTTP Content-Type request header must be set."),
+		}
+	}
+	if strings.HasPrefix(string(r.MediaMetadata.UploadName), "~") {
+		return &util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.Unknown("File name must not begin with '~'."),
+		}
+	}
+	// TODO: Validate filename - what are the valid characters?
+	if r.MediaMetadata.UserID != "" {
+		// TODO: We should put user ID parsing code into gomatrixserverlib and use that instead
+		//       (see https://github.com/matrix-org/gomatrixserverlib/blob/3394e7c7003312043208aa73727d2256eea3d1f6/eventcontent.go#L347 )
+		//       It should be a struct (with pointers into a single string to avoid copying) and
+		//       we should update all refs to use UserID types rather than strings.
+		// https://github.com/matrix-org/synapse/blob/v0.19.2/synapse/types.py#L92
+		if _, _, err := gomatrixserverlib.SplitID('@', string(r.MediaMetadata.UserID)); err != nil {
+			return &util.JSONResponse{
+				Code: http.StatusBadRequest,
+				JSON: jsonerror.BadJSON("user id must be in the form @localpart:domain"),
+			}
+		}
+	}
+	return nil
+}
+
+// storeFileAndMetadata moves the temporary file to its final path based on metadata and stores the metadata in the database
+// See getPathFromMediaMetadata in fileutils for details of the final path.
+// The order of operations is important as it avoids metadata entering the database before the file
+// is ready, and if we fail to move the file, it never gets added to the database.
+// Returns a util.JSONResponse error and cleans up directories in case of error.
+func (r *uploadRequest) storeFileAndMetadata(
+	ctx context.Context,
+	tmpDir types.Path,
+	absBasePath config.Path,
+	db *storage.Database,
+	thumbnailSizes []config.ThumbnailSize,
+	activeThumbnailGeneration *types.ActiveThumbnailGeneration,
+	maxThumbnailGenerators int,
+) *util.JSONResponse {
+	finalPath, duplicate, err := fileutils.MoveFileWithHashCheck(tmpDir, r.MediaMetadata, absBasePath, r.Logger)
+	if err != nil {
+		r.Logger.WithError(err).Error("Failed to move file.")
+		return &util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.Unknown("Failed to upload"),
+		}
+	}
+	if duplicate {
+		r.Logger.WithField("dst", finalPath).Info("File was stored previously - discarding duplicate")
+	}
+
+	if err = db.StoreMediaMetadata(ctx, r.MediaMetadata); err != nil {
+		r.Logger.WithError(err).Warn("Failed to store metadata")
+		// If the file is a duplicate (has the same hash as an existing file) then
+		// there is valid metadata in the database for that file. As such we only
+		// remove the file if it is not a duplicate.
+		if !duplicate {
+			fileutils.RemoveDir(types.Path(path.Dir(string(finalPath))), r.Logger)
+		}
+		return &util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.Unknown("Failed to upload"),
+		}
+	}
+
+	go func() {
+		busy, err := thumbnailer.GenerateThumbnails(
+			context.Background(), finalPath, thumbnailSizes, r.MediaMetadata,
+			activeThumbnailGeneration, maxThumbnailGenerators, db, r.Logger,
+		)
+		if err != nil {
+			r.Logger.WithError(err).Warn("Error generating thumbnails")
+		}
+		if busy {
+			r.Logger.Warn("Maximum number of active thumbnail generators reached. Skipping pre-generation.")
+		}
+	}()
+
+	return nil
+}