Download
From Documentation
Since 1.1.0
We usually implement file downloading through Filedownload when some events are triggered [1]. Following is a simple implementation of downloading a file:
download.zul
<zk>
<div apply="DownloadComposer">
<button id="btn" label="download" />
</div>
</zk>
DownloadComposer.java
public class DownloadComposer extends GenericForwardComposer {
@Listen("onClick=#btn")
public void download() throws IOException {
Filedownload.save("/hello.txt", "application/octet-stream");
}
}
The download mechanism is a process involving two steps. When you invoke save()
, the Filedownload
simply notifies ZK client engine of the download URL. Then, ZK client engine downloads such file according to the referred URL.
Notes
- ↑ For more details, please refer to ZK_Component_Reference/Essential_Components/Filedownload
Download Files in a Test Case
In order to simulate the behavior of the ZK client engine, ZATS Mimic introduces the Resource
interface which represents a downloadable resource file saved on the server. General steps for testing a download function are as follows:
- perform some operations to trigger the download function, e.g. click a button
- check the presence of a downloadable resource through a desktop agent
- fetch and verify the information or content of the resource
@Test
public void test() throws Exception {
DesktopAgent desktop = Zats.newClient().connect("/essentials/download.zul");
Assert. assertNull (desktop. getDownloadable ());
desktop.query("#btn").click();
Resource resource = desktop.getDownloadable();
Assert.assertNotNull(resource);
Assert.assertEquals("hello..txt", resource.getName());
String content = fetchContent(resource.getInputStream());
Assert.assertEquals("Hello world!", content);
}
- Line 14: Click the button to trigger downloading.
- Line 15-16: Since ZATS Mimic handles the response from ZK application automatically, we can retrieve current downloadable resource files from
DesktopAgent.getDownloadable()
. If the method returns anull
when attempting to retrieve downloadable resources, it indicates that there are no downloadable resources after the previous operation. - Line 17-19: We can get more information from
Resource
, or fetch the content of resource files in binary through the input stream to verify the result.