/**
* Call api endpoint
*
* @param verb http-method to use, like: GET, POST, PUT, DELETE, PATCH
* @param url the api-url to call
* @return the output of the api-call, can be a JSON-string
*/
private String call(Verb verb, String url) {
String urlEnd = url;
if (!url.startsWith("/")) {
urlEnd = "/" + url;
}
OAuthRequest request = new OAuthRequest(verb, "https://graph.facebook.com/v2.2" + urlEnd);
request.addHeader("Authorization", "Bearer " + accessTokenString);
Response response = request.send();
return response.getBody();
}
/*
* posts an image to the users news feed
* @param message to show
* @param image as form data
* @return the new image id if successful
*/
public String publishPicture(String msg, Image image, String placeId) throws IOException {
OAuthRequest request =
new OAuthRequest(Verb.POST, "https://graph.facebook.com/v2.2/me/photos"); // request node
request.addHeader("Authorization", "Bearer " + accessTokenString); // authentificate
// check input to avoid error responses
if (msg != null && image != null) {
// facebook requires multipart post structure
MultipartEntityBuilder builder = MultipartEntityBuilder.create();
builder.addTextBody("message", msg); // description
if (placeId != null && !"".equals(placeId)) {
builder.addTextBody(
"place", placeId); // add link to FabLab site if property is set in preferences
}
// convert image to bytearray and append to multipart
BufferedImage bimage =
new BufferedImage(
image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_ARGB);
Graphics2D bGr = bimage.createGraphics();
bGr.drawImage(image, 0, 0, null);
bGr.dispose();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(bimage, "png", baos);
builder.addBinaryBody(msg, baos.toByteArray(), ContentType.MULTIPART_FORM_DATA, "test.png");
// generate multipart byte stream and add to payload of post package
HttpEntity multipart = builder.build();
ByteArrayOutputStream multipartOutStream =
new ByteArrayOutputStream((int) multipart.getContentLength());
multipart.writeTo(multipartOutStream);
request.addPayload(multipartOutStream.toByteArray());
// set header of post package
Header contentType = multipart.getContentType();
request.addHeader(contentType.getName(), contentType.getValue());
// send and response answer
Response response = request.send();
return response.getBody();
} else {
throw new RuntimeException(CONSTANTS.get(FACEBOOK_MESSAGE_IMG_NEEDED));
}
}