#include <Wt/WFileResource>
Public Member Functions | |
WFileResource (const std::string &mimeType, const std::string &fileName, WObject *parent=0) | |
Create a new resource with given mime-type and contents stored in filename. | |
~WFileResource () | |
Destroy the resource. | |
void | setFileName (const std::string &fileName) |
Set a (different) filename. | |
const std::string & | fileName () const |
Get the filename. | |
void | setMimeType (const std::string &mimeType) |
Set the mime-type. | |
const std::string & | mimeType () const |
Get the mime-type. | |
void | setBufferSize (int size) |
Configure the buffer size. | |
int | bufferSize () const |
Returns the buffer size. | |
Protected Member Functions | |
virtual void | handleRequest (const Http::Request &request, Http::Response &response) |
Handle a request. |
To update the resource, either use setFileName() to point it to a new file, or emit the WResource::dataChanged() signal when only the file contents has changed, but not the filename.
The resource makes use of continuations to transmit data piecewise, without blocking a thread or requiring the entire file to be read in memory. The size of the buffer can be changed using setBufferSize().
Usage examples:
Wt::WFileResource *csvFile = new Wt::WFileResource("text/csv", "/opt/files/afile.csv"); csvFile->suggestFileName("data.csv"); Wt::WAnchor *anchor = new Wt::WAnchor(csvFile, "CSV data"); Wt::WFileResource *imageFile = new Wt::WFileResource("image/png", "/opt/files/image.png"); imageFile->suggestFileName("data.png"); Wt::WImage *image = new Wt::WImage(imageFile, "PNG version");
Wt::WFileResource::~WFileResource | ( | ) |
Destroy the resource.
It is up to the user to make sure that the resource is nog longer in use (by e.g. a WImage).
void Wt::WFileResource::setFileName | ( | const std::string & | fileName | ) |
Set a (different) filename.
Set the location of the file on the local filesystem which must be streamed for this resource.
void Wt::WFileResource::setBufferSize | ( | int | size | ) |
Configure the buffer size.
This configures the size of the buffer used to transmit the file piece by piece.
int Wt::WFileResource::bufferSize | ( | ) | const [inline] |
void Wt::WFileResource::handleRequest | ( | const Http::Request & | request, | |
Http::Response & | response | |||
) | [protected, virtual] |
Handle a request.
Reimplement this method so that a proper response is generated for the given request. From the request object you can access request parameters and whether the request is a continuation request. In the response object, you should set the mime type and stream the output data.
A request may also concern a continuation, indicated in Http::Request::continuation(), in which case the next part for a previously created continuation should be served.
While handling a request, which may happen at any time together with event handling, the library makes sure that the resource is not being concurrently deleted, but multiple requests may happend simultaneously for a single resource.
Implements Wt::WResource.