Tomcat permission denied when trying to write a file

Question

I am trying to send a zip via tomcat server. But when I try to access http://localhost:8094/fetna-project-rest/webapi/retdoc/10 I got a permission error which I included in the bottom. I run the server on ubuntu. Can you please help me? My source codes are here:

public static void addToZipFile(String fileName, ZipOutputStream zos) throws FileNotFoundException, IOException {

    System.out.println("Writing '" + fileName + "' to zip file");

    File file = new File(fileName);
    if (!file.exists()) {
        file.createNewFile();
    }

    FileInputStream fis;
    fis = new FileInputStream(file);
    ZipEntry zipEntry = new ZipEntry(fileName);
    zos.putNextEntry(zipEntry);

    byte[] bytes = new byte[1024];
    int length;
    while ((length = fis.read(bytes)) >= 0) {
        zos.write(bytes, 0, length);
    }

    zos.closeEntry();
    fis.close();
}

@GET
@Path("retdoc/{id}")
@Produces(MediaType.APPLICATION_OCTET_STREAM)
public Response retrieveDocument(@PathParam("id") String ID) throws IOException {

    FileOutputStream fos = new FileOutputStream("test.zip");
    ZipOutputStream zos = new ZipOutputStream(fos);

    String file1Name = "test.txt";

    addToZipFile(file1Name, zos);
    zos.close();
    fos.close();
    File zippedFile = new File("test.zip");
    return Response.ok(FileUtils.readFileToByteArray(zippedFile))
            .type("application/zip")
            .header("Content-Disposition", "attachment; filename=\"retrievedDocuments.zip\"")
            .build();
}

and my stacktrace:

message org.glassfish.jersey.server.ContainerException: java.io.FileNotFoundException: test.zip (Permission denied)

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: org.glassfish.jersey.server.ContainerException: java.io.FileNotFoundException: test.zip (Permission denied)
    org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:487)
    org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:425)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:383)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:336)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:223)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause

org.glassfish.jersey.server.ContainerException: java.io.FileNotFoundException: test.zip (Permission denied)
    org.glassfish.jersey.servlet.internal.ResponseWriter.rethrow(ResponseWriter.java:278)
    org.glassfish.jersey.servlet.internal.ResponseWriter.failure(ResponseWriter.java:260)
    org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:509)
    org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:334)
    org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)
    org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)
    org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    org.glassfish.jersey.internal.Errors.process(Errors.java:267)
    org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)
    org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305)
    org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154)
    org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:471)
    org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:425)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:383)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:336)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:223)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause

java.io.FileNotFoundException: test.zip (Permission denied)
    java.io.FileOutputStream.open(Native Method)
    java.io.FileOutputStream.<init>(FileOutputStream.java:221)
    java.io.FileOutputStream.<init>(FileOutputStream.java:110)
    org.eu.srdc.ehealth.MyResource.retrieveDocument(MyResource.java:78)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:606)
    org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory$1.invoke(ResourceMethodInvocationHandlerFactory.java:81)
    org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:144)
    org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:161)
    org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:160)
    org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:99)
    org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:389)
    org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:347)
    org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:102)
    org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:326)
    org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)
    org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)
    org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    org.glassfish.jersey.internal.Errors.process(Errors.java:267)
    org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)
    org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305)
    org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154)
    org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:471)
    org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:425)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:383)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:336)
    org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:223)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/8.0.30 logs.

Answer 1

The user running tomcat doesn't have permission to write the file, just as the error says it. Would suggest you choose a specific folder where your uploaded files will be saved to and give the tomcat user write permissions to it (change username and path accordingly):

$ sudo mkdir /home/tomcat/uploads
$ sudo chown tomcat:tomcat /home/tomcat/uploads
$ sudo chmod u+wrx /home/tomcat/uploads

Then change your servlet code to use the upload path (modified line below):

FileOutputStream fos = new FileOutputStream("/home/tomcat/uploads/test.zip");