Sending a photo to the tumblr API

[Nigey Nige]

So I've been wrestling with this problem for a while, trying to code my first network-enabled app. The purpose of my program is to upload a directory of images to the user's blog using the Tumblr API, found here.

The Write API is a very simple HTTP interface. To create a post, send a POST request to http://www.tumblr.com/api/write with the following parameters:

email - Your account's email address.
password - Your account's password.
type - The post type.
(content parameters) - These vary by post type.

These are the valid values for the type parameter, with the associated content parameters that each type supports:

regular - Requires at least one:
-title
-body (HTML allowed)
photo - Requires either source or data, but not both. If both are specified, source is used.
-source - The URL of the photo to copy. This must be a web-accessible URL, not a local file or intranet location.
-data - An image file. See File uploads below.
-caption (optional, HTML allowed)
-click-through-url (optional)

File uploads can be done in a data parameter where specified above. You may use either of the common encoding methods:

multipart/form-data method, like a file upload box in a web form. Maximum size:
-50 MB for videos
-10 MB for photos
-10 MB for audio
This is recommended since there's much less overhead.
Normal POST method, in which the file's entire binary contents are URL-encoded like any other POST variable. Maximum size:
-5 MB for videos
-5 MB for photos
-5 MB for audio

So I read up on how to perform POST requests, and I managed to send a text post successfully to my blog with the following code:

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;


public class TextPost {
	
	String data = null;
	String enc = "UTF-8";
	
	public TextPost(String type, String title, String body, String tags) throws UnsupportedEncodingException {
		
		//Construct data
		data = URLEncoder.encode("email", enc) + "=" + URLEncoder.encode(Main.getEmail(), enc);
		data += "&" + URLEncoder.encode("password", enc) + "=" + URLEncoder.encode(Main.getPassword(), enc);
		data += "&" + URLEncoder.encode("type", enc) + "=" + URLEncoder.encode(type, enc);
		data += "&" + URLEncoder.encode("title", enc) + "=" + URLEncoder.encode(title, enc);
		data += "&" + URLEncoder.encode("body", enc) + "=" + URLEncoder.encode(body, enc);
		data += "&" + URLEncoder.encode("generator", "UTF-8") + "=" + URLEncoder.encode(Main.getVersion(), "UTF-8");
		data += "&" + URLEncoder.encode("tags", "UTF-8") + "=" + URLEncoder.encode(tags, "UTF-8");
		
	}
	
	public void send() throws IOException {
		// Set up connection
		URL tumblrWrite = new URL("http://www.tumblr.com/api/write");
		HttpURLConnection http = (HttpURLConnection) tumblrWrite.openConnection();
		http.setDoOutput(true);
		http.setRequestMethod("POST");
		OutputStreamWriter out = new OutputStreamWriter(http.getOutputStream());
		
		// Send data
		http.connect();
		out.write(data);
		out.flush();
		System.out.println(http.getResponseCode());
		System.out.println(http.getResponseMessage());
		out.close();
	}
	
}

That works wonderfully. The problem I face now is how to add an image as the data parameter for the post type photo. I've tried what feels like everything, but all I get are 400 bad request errors.

Here's my ImagePost class at the moment, but it's gone through so many iterations of trial and error that it no longer makes any sense to me. Can anyone explain to me how I go about this?

import java.net.*;
import java.io.*;

import org.apache.http.HttpConnection;
import org.apache.http.HttpEntity;
import org.apache.http.HttpRequest;
import org.apache.http.params.HttpParams;
import org.apache.http.util.EntityUtils;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.FileEntity;

public class ImagePost {
	
	HttpRequest request;
	HttpParams formparams;
	HttpEntity image;
	
	public ImagePost(String type, String imgPath, String caption, String tags) {
		image = new FileEntity(new File(imgPath), "image/png");
		
		formparams.setParameter("email", Main.getEmail());
		formparams.setParameter("password", Main.getPassword());
		formparams.setParameter("type", type);
		formparams.setParameter("caption", caption);
		formparams.setParameter("generator", Main.getVersion());
		formparams.setParameter("tags", tags);
		try {
			formparams.setParameter("data", EntityUtils.toByteArray(image));
		} catch (Exception e) {
			System.out.println("Error setting image as parameter.");
			e.printStackTrace();
		}
		request = new HttpPost();
		request.setParams(formparams);
	}

	public void send() throws IOException {
		URL tumblrWrite = new URL("http://www.tumblr.com/api/write");
		HttpConnection hc = (HttpConnection) tumblrWrite.openConnection();
		
	}
	
	
}

[Abhay Agarwal]

I have not used Tumblr API before but just want to add -
I guess you are not encoding your data parameter(image).
As per API, data parameter should be image file and it has to be encoded also.

~ abhay