package downloader import ( "context" "errors" "fmt" "io" "net/http" "path" "strconv" "strings" "time" "github.com/nspcc-dev/neofs-api-go/pkg/client" cid "github.com/nspcc-dev/neofs-api-go/pkg/container/id" "github.com/nspcc-dev/neofs-api-go/pkg/object" "github.com/nspcc-dev/neofs-http-gw/tokens" "github.com/nspcc-dev/neofs-sdk-go/pkg/pool" "github.com/valyala/fasthttp" "go.uber.org/zap" "google.golang.org/grpc/codes" "google.golang.org/grpc/status" ) type ( detector struct { io.Reader err error contentType string done chan struct{} data []byte } request struct { *fasthttp.RequestCtx log *zap.Logger } objectIDs []*object.ID errReader struct { data []byte err error offset int } ) func newReader(data []byte, err error) *errReader { return &errReader{data: data, err: err} } func (r *errReader) Read(b []byte) (int, error) { if r.offset >= len(r.data) { return 0, io.EOF } n := copy(b, r.data[r.offset:]) r.offset += n if r.offset >= len(r.data) { return n, r.err } return n, nil } const contentTypeDetectSize = 512 func newDetector() *detector { return &detector{done: make(chan struct{}), data: make([]byte, contentTypeDetectSize)} } func (d *detector) Wait() { <-d.done } func (d *detector) SetReader(reader io.Reader) { d.Reader = reader } func (d *detector) Detect() { n, err := d.Reader.Read(d.data) if err != nil && err != io.EOF { d.err = err return } d.data = d.data[:n] d.contentType = http.DetectContentType(d.data) close(d.done) } func (d *detector) MultiReader() io.Reader { return io.MultiReader(newReader(d.data, d.err), d.Reader) } func isValidToken(s string) bool { for _, c := range s { if c <= ' ' || c > 127 { return false } if strings.ContainsRune("()<>@,;:\\\"/[]?={}", c) { return false } } return true } func isValidValue(s string) bool { for _, c := range s { // HTTP specification allows for more technically, but we don't want to escape things. if c < ' ' || c > 127 || c == '"' { return false } } return true } func (r *request) receiveFile(clnt client.Object, objectAddress *object.Address) { var ( err error dis = "inline" start = time.Now() filename string obj *object.Object ) if err = tokens.StoreBearerToken(r.RequestCtx); err != nil { r.log.Error("could not fetch and store bearer token", zap.Error(err)) r.Error("could not fetch and store bearer token", fasthttp.StatusBadRequest) return } readDetector := newDetector() options := new(client.GetObjectParams). WithAddress(objectAddress). WithPayloadReaderHandler(func(reader io.Reader) { readDetector.SetReader(reader) readDetector.Detect() }) obj, err = clnt.GetObject( r.RequestCtx, options, ) if err != nil { r.log.Error( "could not receive object", zap.Stringer("elapsed", time.Since(start)), zap.Error(err), ) var ( msg = fmt.Sprintf("could not receive object: %v", err) code = fasthttp.StatusBadRequest cause = err ) for unwrap := errors.Unwrap(err); unwrap != nil; unwrap = errors.Unwrap(cause) { cause = unwrap } if st, ok := status.FromError(cause); ok && st != nil { if st.Code() == codes.NotFound { code = fasthttp.StatusNotFound } msg = st.Message() } r.Error(msg, code) return } if r.Request.URI().QueryArgs().GetBool("download") { dis = "attachment" } r.Response.SetBodyStream(readDetector.MultiReader(), int(obj.PayloadSize())) r.Response.Header.Set("Content-Length", strconv.FormatUint(obj.PayloadSize(), 10)) var contentType string for _, attr := range obj.Attributes() { key := attr.Key() val := attr.Value() if !isValidToken(key) || !isValidValue(val) { continue } r.Response.Header.Set("X-Attribute-"+key, val) switch key { case object.AttributeFileName: filename = val case object.AttributeTimestamp: value, err := strconv.ParseInt(val, 10, 64) if err != nil { r.log.Info("couldn't parse creation date", zap.String("key", key), zap.String("val", val), zap.Error(err)) continue } r.Response.Header.Set("Last-Modified", time.Unix(value, 0).UTC().Format(http.TimeFormat)) case object.AttributeContentType: contentType = val } } r.Response.Header.Set("x-object-id", obj.ID().String()) r.Response.Header.Set("x-owner-id", obj.OwnerID().String()) r.Response.Header.Set("x-container-id", obj.ContainerID().String()) if len(contentType) == 0 { if readDetector.err != nil { r.log.Error("could not read object", zap.Error(err)) r.Error("could not read object", fasthttp.StatusBadRequest) return } readDetector.Wait() contentType = readDetector.contentType } r.SetContentType(contentType) r.Response.Header.Set("Content-Disposition", dis+"; filename="+path.Base(filename)) } func (o objectIDs) Slice() []string { res := make([]string, 0, len(o)) for _, oid := range o { res = append(res, oid.String()) } return res } // Downloader is a download request handler. type Downloader struct { log *zap.Logger pool pool.Pool } // New creates an instance of Downloader using specified options. func New(ctx context.Context, log *zap.Logger, conns pool.Pool) (*Downloader, error) { var err error d := &Downloader{log: log, pool: conns} if err != nil { return nil, fmt.Errorf("failed to get neofs client's reusable artifacts: %w", err) } return d, nil } func (d *Downloader) newRequest(ctx *fasthttp.RequestCtx, log *zap.Logger) *request { return &request{ RequestCtx: ctx, log: log, } } // DownloadByAddress handles download requests using simple cid/oid format. func (d *Downloader) DownloadByAddress(c *fasthttp.RequestCtx) { var ( err error address = object.NewAddress() cid, _ = c.UserValue("cid").(string) oid, _ = c.UserValue("oid").(string) val = strings.Join([]string{cid, oid}, "/") log = d.log.With(zap.String("cid", cid), zap.String("oid", oid)) ) if err = address.Parse(val); err != nil { log.Error("wrong object address", zap.Error(err)) c.Error("wrong object address", fasthttp.StatusBadRequest) return } d.newRequest(c, log).receiveFile(d.pool, address) } // DownloadByAttribute handles attribute-based download requests. func (d *Downloader) DownloadByAttribute(c *fasthttp.RequestCtx) { var ( err error scid, _ = c.UserValue("cid").(string) key, _ = c.UserValue("attr_key").(string) val, _ = c.UserValue("attr_val").(string) log = d.log.With(zap.String("cid", scid), zap.String("attr_key", key), zap.String("attr_val", val)) ids []*object.ID ) cid := cid.New() if err = cid.Parse(scid); err != nil { log.Error("wrong container id", zap.Error(err)) c.Error("wrong container id", fasthttp.StatusBadRequest) return } options := object.NewSearchFilters() options.AddRootFilter() options.AddFilter(key, val, object.MatchStringEqual) sops := new(client.SearchObjectParams).WithContainerID(cid).WithSearchFilters(options) if ids, err = d.pool.SearchObject(c, sops); err != nil { log.Error("something went wrong", zap.Error(err)) c.Error("something went wrong", fasthttp.StatusBadRequest) return } else if len(ids) == 0 { log.Debug("object not found") c.Error("object not found", fasthttp.StatusNotFound) return } if len(ids) > 1 { log.Debug("found multiple objects", zap.Strings("object_ids", objectIDs(ids).Slice()), zap.Stringer("show_object_id", ids[0])) } address := object.NewAddress() address.SetContainerID(cid) address.SetObjectID(ids[0]) d.newRequest(c, log).receiveFile(d.pool, address) }