 		logger.info("uandle update preview called")
 		do {
 			let cmd = try coder.updatePreview(previewId: updateData.previewId, chunkNumber: updateData.chunkId, includePrevious: updateData.includePrevious)
+			if cmd.count < 1 { logger.info("sending empty data") }
 			try worker?.send(data: cmd)
 		} catch {
 			logger.warning("error geupdating preview: \(error)")

				// ask for updated values
				cmd = try coder.listVariables(deltaOnly: false, contextId: params.environmentId)
			}
			try worker?.send(data: cmd)
			watchingVariables = shouldWatch
		} catch {

		logger.info("handleInitPreview called")
		do {
			let cmd = try coder.initPreview(fileId: updateData.fileId, updateIdentifier: updateData.updateIdentifier)
			if cmd.count < 1 { logger.info("sending empty data") }
			try worker?.send(data: cmd)
		} catch {
			logger.warning("error initing preview: \(error)")
