mediaapi/writers/download: Add local download support

This commit is contained in:
Robert Swain 2017-05-31 13:46:21 +02:00
parent 3f7ef7690b
commit a936ad5063
2 changed files with 169 additions and 3 deletions

View file

@ -54,7 +54,7 @@ func Setup(servMux *http.ServeMux, httpClient *http.Client, cfg *config.MediaAPI
w.Header().Set("Content-Type", "application/json")
vars := mux.Vars(req)
writers.Download(w, req, gomatrixserverlib.ServerName(vars["serverName"]), types.MediaID(vars["mediaId"]), cfg, activeRemoteRequests)
writers.Download(w, req, gomatrixserverlib.ServerName(vars["serverName"]), types.MediaID(vars["mediaId"]), cfg, db, activeRemoteRequests)
})),
)

View file

@ -15,14 +15,20 @@
package writers
import (
"database/sql"
"encoding/json"
"fmt"
"io"
"net/http"
"os"
"regexp"
"strconv"
log "github.com/Sirupsen/logrus"
"github.com/matrix-org/dendrite/clientapi/jsonerror"
"github.com/matrix-org/dendrite/mediaapi/config"
"github.com/matrix-org/dendrite/mediaapi/fileutils"
"github.com/matrix-org/dendrite/mediaapi/storage"
"github.com/matrix-org/dendrite/mediaapi/types"
"github.com/matrix-org/gomatrixserverlib"
"github.com/matrix-org/util"
@ -33,6 +39,13 @@ const mediaIDCharacters = "A-Za-z0-9_=-"
// Note: unfortunately regex.MustCompile() cannot be assigned to a const
var mediaIDRegex = regexp.MustCompile("[" + mediaIDCharacters + "]+")
// Error types used by downloadRequest.getMediaMetadata
// FIXME: make into types
var (
errDBQuery = fmt.Errorf("error querying database for media")
errDBNotFound = fmt.Errorf("media not found")
)
// downloadRequest metadata included in or derivable from an download request
// https://matrix.org/docs/spec/client_server/r0.2.0.html#get-matrix-media-r0-download-servername-mediaid
type downloadRequest struct {
@ -41,7 +54,8 @@ type downloadRequest struct {
}
// Download implements /download
func Download(w http.ResponseWriter, req *http.Request, origin gomatrixserverlib.ServerName, mediaID types.MediaID, cfg *config.MediaAPI, activeRemoteRequests *types.ActiveRemoteRequests) {
// Files from this server (i.e. origin == cfg.ServerName) are served directly
func Download(w http.ResponseWriter, req *http.Request, origin gomatrixserverlib.ServerName, mediaID types.MediaID, cfg *config.MediaAPI, db *storage.Database, activeRemoteRequests *types.ActiveRemoteRequests) {
r := &downloadRequest{
MediaMetadata: &types.MediaMetadata{
MediaID: mediaID,
@ -64,7 +78,10 @@ func Download(w http.ResponseWriter, req *http.Request, origin gomatrixserverlib
return
}
// doDownload
if resErr := r.doDownload(w, cfg, db, activeRemoteRequests); resErr != nil {
r.jsonErrorResponse(w, *resErr)
return
}
}
func (r *downloadRequest) jsonErrorResponse(w http.ResponseWriter, res util.JSONResponse) {
@ -101,3 +118,152 @@ func (r *downloadRequest) Validate() *util.JSONResponse {
}
return nil
}
func (r *downloadRequest) doDownload(w http.ResponseWriter, cfg *config.MediaAPI, db *storage.Database, activeRemoteRequests *types.ActiveRemoteRequests) *util.JSONResponse {
// check if we have a record of the media in our database
mediaMetadata, err := r.getMediaMetadata(db)
if err == nil {
// If we have a record, we can respond from the local file
r.MediaMetadata = mediaMetadata
return r.respondFromLocalFile(w, cfg.AbsBasePath)
} else if err == errDBNotFound {
if r.MediaMetadata.Origin == cfg.ServerName {
// If we do not have a record and the origin is local, the file is not found
r.Logger.WithError(err).Warn("Failed to look up file in database")
return &util.JSONResponse{
Code: 404,
JSON: jsonerror.NotFound(fmt.Sprintf("File with media ID %q does not exist", r.MediaMetadata.MediaID)),
}
}
// TODO: If we do not have a record and the origin is remote, we need to fetch it and respond with that file
return &util.JSONResponse{
Code: 404,
JSON: jsonerror.NotFound(fmt.Sprintf("File with media ID %q does not exist", r.MediaMetadata.MediaID)),
}
}
// Another error from the database
r.Logger.WithError(err).WithFields(log.Fields{
"MediaID": r.MediaMetadata.MediaID,
"Origin": r.MediaMetadata.Origin,
}).Error("Error querying the database.")
return &util.JSONResponse{
Code: 500,
JSON: jsonerror.InternalServerError(),
}
}
// getMediaMetadata queries the database for media metadata
func (r *downloadRequest) getMediaMetadata(db *storage.Database) (*types.MediaMetadata, error) {
mediaMetadata, err := db.GetMediaMetadata(r.MediaMetadata.MediaID, r.MediaMetadata.Origin)
if err != nil {
if err == sql.ErrNoRows {
r.Logger.WithFields(log.Fields{
"Origin": r.MediaMetadata.Origin,
"MediaID": r.MediaMetadata.MediaID,
}).Info("Media not found in database.")
return nil, errDBNotFound
}
r.Logger.WithError(err).WithFields(log.Fields{
"Origin": r.MediaMetadata.Origin,
"MediaID": r.MediaMetadata.MediaID,
}).Error("Error querying database for media.")
return nil, errDBQuery
}
return mediaMetadata, nil
}
// respondFromLocalFile reads a file from local storage and writes it to the http.ResponseWriter
// Returns a util.JSONResponse error in case of error
func (r *downloadRequest) respondFromLocalFile(w http.ResponseWriter, absBasePath types.Path) *util.JSONResponse {
filePath, err := fileutils.GetPathFromBase64Hash(r.MediaMetadata.Base64Hash, absBasePath)
if err != nil {
// FIXME: Remove erroneous file from database?
r.Logger.WithError(err).Warn("Failed to get file path from metadata")
return &util.JSONResponse{
Code: 404,
JSON: jsonerror.NotFound(fmt.Sprintf("File with media ID %q does not exist", r.MediaMetadata.MediaID)),
}
}
file, err := os.Open(filePath)
defer file.Close()
if err != nil {
// FIXME: Remove erroneous file from database?
r.Logger.WithError(err).Warn("Failed to open file")
return &util.JSONResponse{
Code: 404,
JSON: jsonerror.NotFound(fmt.Sprintf("File with media ID %q does not exist", r.MediaMetadata.MediaID)),
}
}
stat, err := file.Stat()
if err != nil {
// FIXME: Remove erroneous file from database?
r.Logger.WithError(err).Warn("Failed to stat file")
return &util.JSONResponse{
Code: 404,
JSON: jsonerror.NotFound(fmt.Sprintf("File with media ID %q does not exist", r.MediaMetadata.MediaID)),
}
}
if r.MediaMetadata.FileSizeBytes > 0 && int64(r.MediaMetadata.FileSizeBytes) != stat.Size() {
r.Logger.WithFields(log.Fields{
"fileSizeDatabase": r.MediaMetadata.FileSizeBytes,
"fileSizeDisk": stat.Size(),
}).Warn("File size in database and on-disk differ.")
// FIXME: Remove erroneous file from database?
}
r.Logger.WithFields(log.Fields{
"MediaID": r.MediaMetadata.MediaID,
"Origin": r.MediaMetadata.Origin,
"UploadName": r.MediaMetadata.UploadName,
"Base64Hash": r.MediaMetadata.Base64Hash,
"FileSizeBytes": r.MediaMetadata.FileSizeBytes,
"Content-Type": r.MediaMetadata.ContentType,
}).Info("Responding with file")
w.Header().Set("Content-Type", string(r.MediaMetadata.ContentType))
w.Header().Set("Content-Length", strconv.FormatInt(int64(r.MediaMetadata.FileSizeBytes), 10))
contentSecurityPolicy := "default-src 'none';" +
" script-src 'none';" +
" plugin-types application/pdf;" +
" style-src 'unsafe-inline';" +
" object-src 'self';"
w.Header().Set("Content-Security-Policy", contentSecurityPolicy)
if bytesResponded, err := io.Copy(w, file); err != nil {
r.Logger.WithError(err).Warn("Failed to copy from cache")
if bytesResponded == 0 {
return &util.JSONResponse{
Code: 500,
JSON: jsonerror.NotFound(fmt.Sprintf("Failed to respond with file with media ID %q", r.MediaMetadata.MediaID)),
}
}
// If we have written any data then we have already responded with 200 OK and all we can do is close the connection
// FIXME: close the connection here or just return?
r.closeConnection(w)
}
return nil
}
func (r *downloadRequest) closeConnection(w http.ResponseWriter) {
r.Logger.WithFields(log.Fields{
"Origin": r.MediaMetadata.Origin,
"MediaID": r.MediaMetadata.MediaID,
}).Info("Attempting to close the connection.")
hijacker, ok := w.(http.Hijacker)
if ok {
connection, _, hijackErr := hijacker.Hijack()
if hijackErr == nil {
r.Logger.WithFields(log.Fields{
"Origin": r.MediaMetadata.Origin,
"MediaID": r.MediaMetadata.MediaID,
}).Info("Closing")
connection.Close()
} else {
r.Logger.WithError(hijackErr).WithFields(log.Fields{
"Origin": r.MediaMetadata.Origin,
"MediaID": r.MediaMetadata.MediaID,
}).Warn("Error trying to hijack and close connection")
}
}
}