def setupOutputs(self):
        if not os.path.exists(self.DescriptionFilePath.value):
            raise OpRESTfulBlockwiseFilesetReader.MissingDatasetError(
                "Dataset description not found: {}".format(
                    self.DescriptionFilePath.value))

        # Load up the class that does the real work
        self._blockwiseFileset = RESTfulBlockwiseFileset(
            self.DescriptionFilePath.value)

        # Check for errors in the description file
        localDescription = self._blockwiseFileset.compositeDescription.local_description
        axes = localDescription.axes
        assert False not in map(
            lambda a: a in 'txyzc',
            axes), "Unknown axis type.  Known axes: txyzc  Your axes:".format(
                axes)

        self.Output.meta.shape = tuple(localDescription.view_shape)
        self.Output.meta.dtype = localDescription.dtype
        self.Output.meta.axistags = vigra.defaultAxistags(
            localDescription.axes)
        drange = localDescription.drange
        if drange is not None:
            self.Output.meta.drange = drange
    def test_1_SingleDownload(self):
        volume = RESTfulBlockwiseFileset(self.descriptionFilePath)

        slicing = numpy.s_[0:20, 0:20, 0:20]
        roi = sliceToRoi(slicing, volume.description.shape)
        data = volume.readData(roi)
        assert data.shape == (20, 20, 20)

        assert volume.getBlockStatus(([0, 0,
                                       0])) == BlockwiseFileset.BLOCK_AVAILABLE
    def test_4_OffsetDownload(self):
        volume = RESTfulBlockwiseFileset(self.descriptionFilePath)

        slicing = numpy.s_[20:40, 20:40, 20:40]
        roi = sliceToRoi(slicing, volume.description.shape)
        data = volume.readData(roi)
        assert data.shape == (20, 20, 20)
        assert volume.getBlockStatus(
            ([20, 20, 20])) == BlockwiseFileset.BLOCK_AVAILABLE

        offsetVolume = RESTfulBlockwiseFileset(self.descriptionFilePath_offset)
        offsetSlicing = numpy.s_[
            20:40, 0:20, 20:
            40]  # Note middle slice is offset (see view_origin in setupClass)
        offsetRoi = sliceToRoi(offsetSlicing, offsetVolume.description.shape)
        offsetData = offsetVolume.readData(offsetRoi)
        assert offsetData.shape == (20, 20, 20)
        assert offsetVolume.getBlockStatus(
            ([20, 0, 20])) == BlockwiseFileset.BLOCK_AVAILABLE

        # Data should be the same
        assert (offsetData == data).all()