I know how to create a plain link to download arbitrary binary data (using ResourceLink with ResourceStreamResource and AbstractResourceStream), but now I want to create a form whose submit button should either redirect to the form again (e.g. to correct an input error) or to download an arbitrary binary data file without going to a different page. How this can be achieved?
For the binary part, try something like this:
final ResourceStreamRequestHandler target = new ResourceStreamRequestHandler(new AbstractResourceStream() {
#Override
public String getContentType() {
return "application/octet-stream";
}
#Override
public InputStream getInputStream() throws ResourceStreamNotFoundException {
return new ByteArrayInputStream(yourBinaryContent);
}
#Override
public void close() throws IOException {
}
});
target.setFileName("response.dat");
target.setContentDisposition(ContentDisposition.ATTACHMENT);
getRequestCycle().scheduleRequestHandlerAfterCurrent(target);
Otherwise, to handle 'text' responses, use the code you already have.
Related
I have a component which allows a user to download an excel file after clicking a link.
It works and everything is fine, but I don't know how to write a test for this component.
I want to write a test to check if after pressing a link a file is sent to a client.
And so, my component looks like this
Link<Void> calculationsLink = new Link<>("calculationsLink") {
#Override
public void onClick() {
AbstractResourceStreamWriter rStream =
new AbstractResourceStreamWriter() {
#Override
public void write(OutputStream output)
throws IOException {
output.write(MyApp.class
.getResourceAsStream(pathToCalculations)
.readAllBytes());
}
};
ResourceStreamRequestHandler handler =
new ResourceStreamRequestHandler(rStream, "calculations.xslx");
getRequestCycle().scheduleRequestHandlerAfterCurrent(handler);
}
};
My test is
#Test
public void calculations_file_downloaded_Successfully() {
// then start and render the base page
tester.startPage(HomePage.class); <-- link is located in a HomePage
tester.clickLink("navBar:calculations", false); <-- link is clickable
tester.getResponse();//????
tester.assert???(?????); <-- how to assert and what to assert?
}
You should use tester.getLastResponse() and assert on its properties.
tester.getResponse() is the MockHttpServletResponse that will be used for the next HTTP call.
Some dummy examples:
assertEquals("application/octet-stream", tester.getLastResponse().getContentType());
assertEquals(3, tester.getLastResponse().getBinaryContent().length);
assertArrayEquals(new byte[] {1, 2, 3}, tester.getLastResponse().getBinaryContent());
I'm attempting to do a POST with the body being an InputStream with something like this:
#POST("/build")
#Headers("Content-Type: application/tar")
Response build(#Query("t") String tag,
#Query("q") boolean quiet,
#Query("nocache") boolean nocache,
#Body TypedInput inputStream);
In this case the InputStream is from a compressed tar file.
What's the proper way to POST an InputStream?
You can upload inputStream using Multipart.
#Multipart
#POST("pictures")
suspend fun uploadPicture(
#Part part: MultipartBody.Part
): NetworkPicture
Then in perhaps your repository class:
suspend fun upload(inputStream: InputStream) {
val part = MultipartBody.Part.createFormData(
"pic", "myPic", RequestBody.create(
MediaType.parse("image/*"),
inputStream.readBytes()
)
)
uploadPicture(part)
}
If you want to find out how to get an image Uri, check this answer: https://stackoverflow.com/a/61592000/10030693
TypedInput is a wrapper around an InputStream that has metadata such as length and content type which is used in making the request. All you need to do is provide a class that implements TypedInput which passed your input stream.
class TarFileInput implements TypedInput {
#Override public InputStream in() {
return /*your input stream here*/;
}
// other methods...
}
Be sure you pass the appropriate return values for length() and mimeType() based on the type of file from which you are streaming content.
You can also optionally pass it as an anonymous implementation when you are calling your build method.
The only solution I came up with here was to use the TypeFile class:
TypedFile tarTypeFile = new TypedFile("application/tar", myFile);
and the interface (without explicitly setting the Content-Type header this time):
#POST("/build")
Response build(#Query("t") String tag,
#Query("q") boolean quiet,
#Query("nocache") boolean nocache,
#Body TypedInput inputStream);
Using my own implementation of TypedInput resulted in a vague EOF exception even while I provided the length().
public class TarArchive implements TypedInput {
private File file;
public TarArchive(File file) {
this.file = file;
}
public String mimeType() {
return "application/tar";
}
public long length() {
return this.file.length();
}
public InputStream in() throws IOException {
return new FileInputStream(this.file);
}
}
Also, while troubleshooting this issue I tried using the latest Apache Http client instead of OkHttp which resulted in a "Content-Length header already present" error even though I wasn't explicitly setting that header.
According to the Multipart section of http://square.github.io/retrofit/ you'll want to use TypedOutput instead of TypedInput. Following their examples for multipart uploads worked fine for me once I had implemented a TypedOutput class.
My solution was to implement TypedOutput
public class TypedStream implements TypedOutput{
private Uri uri;
public TypedStream(Uri uri){
this.uri = uri;
}
#Override
public String fileName() {
return null;
}
#Override
public String mimeType() {
return getContentResolver().getType(uri);
}
#Override
public long length() {
return -1;
}
#Override
public void writeTo(OutputStream out) throws IOException {
Utils.copyStream(getContentResolver().openInputStream(uri), out);
}
}
I use junit to assert the existing of wicket components:
wicketTester.assertComponent("dev1WicketId:dev2WicketId:formWicketId", Form.class);
This works for some forms. For complex structure, it is defficult to find out the path of the form by searching all html files. Is there any method how to find out the path easy?
If you have the component you can call #getPageRelativePath(). E.g.
// Supposing c is a component that has been added to the page.
// Returns the full path to the component relative to the page, e.g., "path:to:label"
String pathToComponent = c.getPageRelativePath();
You can get the children of a markup container by using the visitChildren() method. The following example shows how to get all the Forms from a page.
List<Form> list = new ArrayList<Form<?>>();
Page page = wicketTester.getLastRenderedPage();
for (Form form : page.visitChildren(Form.class)) {
list.add(form);
}
An easy way to get those is to call getDebugSettings().setOutputComponentPath(true); when initializing your application. This will make Wicket to output these paths to the generated HTML as an attribute on every component-bound tag.
It's recommended to only enable this on debug mode, though:
public class WicketApplication extends WebApplication {
#Override
public void init() {
super.init();
if (getConfigurationType() == RuntimeConfigurationType.DEVELOPMENT) {
getDebugSettings().setOutputComponentPath(true);
}
}
}
Extending the RJo's answer.
It seems that the method page.visitChildren(<Class>) is deprecated (Wicket 6), so with an IVisitor it can be :
protected String findPathComponentOnLastRenderedPage(final String idComponent) {
final Page page = wicketTester.getLastRenderedPage();
return page.visitChildren(Component.class, new IVisitor<Component, String>() {
#Override
public void component(final Component component, final IVisit<String> visit) {
if (component.getId().equals(idComponent)) {
visit.stop(component.getPageRelativePath());
}
}
});
}
I am new to GWT and am trying to implement a file upload functionality.
Found some implementation help over the internet and used that as reference.
But have some questions related to that:
The actual upload or writing the contents of file on server(or disk) will be done by a servlet.
Is it necessary that this servlet (say MyFileUploadServlet) extends HttpServlet? OR
I can use RemoteServiceServlet or implement any other interface? If yes, which method do I need to implement/override?
In my servlet, after everything is done, I need to return back the response back to the client.
I think form.addSubmitCompleteHandler() can be used to achieve that. From servlet, I could return text/html (or String type object) and then use SubmitCompleteEvent.getResults() to get the result.
Question is that can I use my custom object instead of String (lets say MyFileUploadResult), populate the results in it and then pass it back to client?
or can I get back JSON object?
Currently, after getting back the response and using SubmitCompleteEvent.getResults(), I am getting some HTML tags added to the actual response such as :
pre> Image upload successfully /pre> .
Is there a way to get rid of that?
Thanks a lot in advance!
Regards,
Ashish
To upload files, I have extended HttpServlet in the past. I used it together with Commons-FileUpload.
I made a general widget for form-based uploads. That was to accommodate uploads for different file types (plain text and Base64). If you just need to upload plain text files, you could combine the following two classes into one.
public class UploadFile extends Composite {
#UiField FormPanel uploadForm;
#UiField FileUpload fileUpload;
#UiField Button uploadButton;
interface Binder extends UiBinder<Widget, UploadFile> {}
public UploadFile() {
initWidget(GWT.<Binder> create(Binder.class).createAndBindUi(this));
fileUpload.setName("fileUpload");
uploadForm.setEncoding(FormPanel.ENCODING_MULTIPART);
uploadForm.setMethod(FormPanel.METHOD_POST);
uploadForm.addSubmitHandler(new SubmitHandler() {
#Override
public void onSubmit(SubmitEvent event) {
if ("".equals(fileUpload.getFilename())) {
Window.alert("No file selected");
event.cancel();
}
}
});
uploadButton.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
uploadForm.submit();
}
});
}
public HandlerRegistration addCompletedCallback(
final AsyncCallback<String> callback) {
return uploadForm.addSubmitCompleteHandler(new SubmitCompleteHandler() {
#Override
public void onSubmitComplete(SubmitCompleteEvent event) {
callback.onSuccess(event.getResults());
}
});
}
}
The UiBinder part is pretty straighforward.
<g:HTMLPanel>
<g:HorizontalPanel>
<g:FormPanel ui:field="uploadForm">
<g:FileUpload ui:field="fileUpload"></g:FileUpload>
</g:FormPanel>
<g:Button ui:field="uploadButton">Upload File</g:Button>
</g:HorizontalPanel>
</g:HTMLPanel>
Now you can extend this class for plain text files. Just make sure your web.xml serves the HttpServlet at /textupload.
public class UploadFileAsText extends UploadFile {
public UploadFileAsText() {
uploadForm.setAction(GWT.getModuleBaseURL() + "textupload");
}
}
The servlet for plain text files goes on the server side. It returns the contents of the uploaded file to the client. Make sure to install the jar for FileUpload from Apache Commons somewhere on your classpath.
public class TextFileUploadServiceImpl extends HttpServlet {
private static final long serialVersionUID = 1L;
#Override
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
if (! ServletFileUpload.isMultipartContent(request)) {
response.sendError(HttpServletResponse.SC_BAD_REQUEST,
"Not a multipart request");
return;
}
ServletFileUpload upload = new ServletFileUpload(); // from Commons
try {
FileItemIterator iter = upload.getItemIterator(request);
if (iter.hasNext()) {
FileItemStream fileItem = iter.next();
// String name = fileItem.getFieldName(); // file name, if you need it
ServletOutputStream out = response.getOutputStream();
response.setBufferSize(32768);
int bufSize = response.getBufferSize();
byte[] buffer = new byte[bufSize];
InputStream in = fileItem.openStream();
BufferedInputStream bis = new BufferedInputStream(in, bufSize);
long length = 0;
int bytes;
while ((bytes = bis.read(buffer, 0, bufSize)) >= 0) {
out.write(buffer, 0, bytes);
length += bytes;
}
response.setContentType("text/html");
response.setContentLength(
(length > 0 && length <= Integer.MAX_VALUE) ? (int) length : 0);
bis.close();
in.close();
out.flush();
out.close();
}
} catch(Exception caught) {
throw new RuntimeException(caught);
}
}
}
I cannot recall how I got around the <pre></pre> tag problem. You may have to filter the tags on the client. The topic is also addressed here.
When I do a request for a profile picture, mine in this case I receive some kind of encoded string in my HttpResponseHandler. The code below is the request for my profile picture.
private static AsyncHttpClient client = new AsyncHttpClient();
client.get("http://graph.facebook.com/1206433/picture", fbPictureHandler);
The code below is my handler to retrieve a response. I get the response as a string, but I am not sure what to do with this response object. I have tried converting to a byte array and writing to "file.jpg" this hasnt worked. My main question is what do I do with this response object?
private static AsyncHttpResponseHandler fbPictureHandler = new AsyncHttpResponseHandler ()
{
#Override
public void onStart() {
Log.d(TAG,"started picture handler");
}
#Override
public void onSuccess(String response) {
//Not sure what to do here, have been unable to do anything with this Byte //array
byte[] imageBackground = response.getBytes();
}
#Override
public void onFailure(Throwable error) {
Log.d(TAG, "unable to retrieve picture");
error.printStackTrace();
}
#Override
public void onFinish() {
Log.d(TAG,"Finished picture handler");
}
};
This is the PrintString of the response object
11-29 19:42:12.640: D/Yatter Facebook(3551): ÿØÿà��JFIF������������ÿþ��;CREATOR: gd-jpeg v1.0 (using IJG JPEG v62), quality = 95
ANy help is greatly appreciated and hopefully this can help others.
Thank you,
Use the following request instead of the one that you are issuing
http://graph.facebook.com/1206433?fields=picture
This will return a JSON string to you in the following format which contains the original path to the profile image.
{
"picture": "http://profile.ak.fbcdn.net/hprofile-ak-snc4/260615_1206433_140418666_q.jpg"
}
Parse this string to get the path of "picture" and use it in your code to get the picture.
Here is a sample request example
NOTE : http://profile.ak.fbcdn.net/hprofile-ak-snc4/260615_1206433_140418666_q.jpg is obtained by parsing the JSON string in the first step.
WebRequest request = WebRequest.Create("http://profile.ak.fbcdn.net/hprofile-ak-snc4/260615_1206433_140418666_q.jpg");
WebResponse response = request.GetResponse();
Stream stream = response.GetResponseStream();
pictureBox1.Image = Image.FromStream(stream);
This will load the image to a picture box in a windows form application.
If you need anymore help let me know.
you can use ?redirect=false follow '/picture' for get direct link
http://graph.facebook.com/+facebookid+/picture?redirect=false
and response contain url static link (json format)
{"data":{
"url":"https:\/\/fbcdn-profile-a.akamaihd.net\/hprofile-ak-frc1\/t1.0-1\/c126.33.409.409\/s50x50\/551571_4079894629426_190963543_n.jpg","is_silhouette":false}
}