uri-resolver/src/main/java/org/gcube/datatransfer/resolver/services/StorageManager.java

package org.gcube.datatransfer.resolver.services;

import java.io.InputStream;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.ResponseBuilder;
import javax.ws.rs.core.Response.Status;
import javax.ws.rs.core.StreamingOutput;

import org.gcube.contentmanagement.blobstorage.resource.MyFile;
import org.gcube.contentmanagement.blobstorage.service.IClient;
import org.gcube.contentmanager.storageclient.wrapper.AccessType;
import org.gcube.contentmanager.storageclient.wrapper.StorageClient;
import org.gcube.datatransfer.resolver.SingleFileStreamingOutput;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Path("/")
public class StorageManager {

	private static Logger logger = LoggerFactory.getLogger(StorageManager.class);
	
	@GET
	@Path("{smpId}")
	public Response getFile(@PathParam("smpId") String smpId) {
		logger.info("resolve Storage Id called");
		StorageClient client = new StorageClient("DataTransfer", "UriResolver", "storageid-resolver", AccessType.PUBLIC);
		IClient iClient = client.getClient();
		String toSEID = iClient.getId(smpId); //to Storage Encrypted ID
		logger.debug("Decoded ID"+" = "+ toSEID);

		if(toSEID==null){
			String error = "Decrypted id is null, thrown exception!";
			throw new WebApplicationException(error, Status.BAD_REQUEST);
		}
		
		long size = iClient.getSize().RFileById(toSEID);
		String fileName="download";
		String contentType=null;
		try{
			MyFile file = client.getClient().getMetaFile().RFile(toSEID);
			logger.debug("MetaFile retrieved from storage? "+ (file!=null));

			fileName= file.getName();
			contentType = file.getMimeType(); 			

		}catch (Exception e) {
			logger.warn("Error when getting file metadata from storage, printing this warning and trying to continue..", e);
		}
		
		logger.info("filename retrieved is {}",fileName);
		
		InputStream streamToWrite=iClient.get().RFileAsInputStream(toSEID); //input stream
		
		StreamingOutput so = new SingleFileStreamingOutput(streamToWrite);
		
		ResponseBuilder response = Response
				.ok(so)
				.header("content-disposition","attachment; filename = \""+fileName+"\"")
				.header("Content-Length", size);
		if (contentType!= null) response.header("Content-Type",contentType);
		return response.build();
	}
	
}