Java: how to use UrlConnection to post request with authorization?

Question

Hi,

I would lake to generate POST request to a server which requires authentication. I tried to use the following method:

private synchronized String CreateNewProductPOST (String urlString, String encodedString, String title, String content, Double price, String tags) {

    String data = "product[title]=" + URLEncoder.encode(title) +
                "&product[content]=" + URLEncoder.encode(content) + 
                "&product[price]=" + URLEncoder.encode(price.toString()) +
                "&tags=" + tags;
    try {
        URL url = new URL(urlString);
        URLConnection conn;
        conn = url.openConnection();
        conn.setRequestProperty ("Authorization", "Basic " + encodedString);
        conn.setDoOutput(true);
        conn.setDoInput(true);
        OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
        wr.write(data);
        wr.flush(); 
        // Get the response 
        BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream())); 
        String line; 
        while ((line = rd.readLine()) != null) { 
            // Process line... 
            } 
        wr.close(); 
        rd.close(); 
        return rd.toString();
    } catch (MalformedURLException e) {

        e.printStackTrace();
        return e.getMessage();
    }
    catch (IOException e) {

        e.printStackTrace();
        return e.getMessage();
    } 
}

but the server doesn't receive the authorization data. The line which is supposed to add authorization data is the following:

conn.setRequestProperty ("Authorization", "Basic " + encodedString);

and the line

BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream())); 

also throws an IOException.

Anyway I would be very thankful if anyone could suggest any fix of the logic above in order to enable authorization using POST with UrlConnection.

but obviously it doesn't work as it is supposed to although if the same logic is used for GET request everything works fine.

Answer 1

A fine example found here.

Okay how about doing this,

    URL url = new URL(urlString);
    URLConnection conn = url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestProperty ("Authorization", encodedCredentials);

    OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

    writer.write(data);
    writer.flush();
    String line;
    BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
    while ((line = reader.readLine()) != null) {
      System.out.println(line);
    }
    writer.close();
    reader.close();

Answer 2

HTTP authorization does not differ between GET and POST requests, so I would first assume that something else is wrong. Instead of setting the Authorization header directly, I would suggest using the java.net.Authorization class, but I am not sure if it solves your problem. Perhaps your server is somehow configured to require a different authorization scheme than "basic" for post requests?

Answer 3

Hi to all, i was looking information about how to do a POST request. I need to specify that mi request is a POST request because, i'm working with RESTful web services that only uses POST methods, and if the request isn't post, when i try to do the request i receive an HTTP error 405. I assure that my code isn't wrong doing the next: I create a method in my web service that is called through GET request and i point my application to consume that web service method and it works. My code is the next:

    URL server = null;
    URLConnection conexion = null;
    BufferedReader reader = null;
    server = new URL("http://localhost:8089/myApp/resources/webService");
    conexion = server.openConnection();
    reader = new BufferedReader(new InputStreamReader(server.openStream()));
    System.out.println(reader.readLine());

Answer 4

I don't see anywhere in the code where you specify that this is a POST request. Then again, you need a java.net.HttpURLConnection to do that.

In fact, I highly recommend using HttpURLConnection instead of URLConnection, with conn.setRequestMethod("POST"); and see if it still gives you problems.