AuthenticatorUtils.java

package org.aksw.jena_sparql_api.web.utils;

import java.util.Arrays;

import javax.servlet.http.HttpServletRequest;
import javax.xml.bind.DatatypeConverter;

import org.aksw.commons.util.strings.StringUtils;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.HttpClient;
import org.apache.http.client.utils.HttpClientUtils;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.client.HttpClientBuilder;

public class AuthenticatorUtils {
	/**
	 * Create a http client with username / password authentication.
	 * If the argument is null, an http client without authentication is returned.
	 *
	 * @param credentials
	 * @return
	 */
	public static HttpClientBuilder prepareHttpClientBuilder(UsernamePasswordCredentials credentials) {
        HttpClientBuilder result = HttpClientBuilder.create();
        if(credentials != null) {
        	CredentialsProvider provider = new BasicCredentialsProvider();
            provider.setCredentials(AuthScope.ANY, credentials);
        	result.setDefaultCredentialsProvider(provider);
        }
        return result;
	}

    public static UsernamePasswordCredentials parseCredentials(HttpServletRequest req) {
    	UsernamePasswordCredentials result = null;
        /*
        Enumeration<String> e = req.getHeaderNames();
        while(e.hasMoreElements()) {
            String name = e.nextElement();
            System.out.println(name + ": " + req.getHeader(name));
        }*/

        String authStr = StringUtils.coalesce(
                req.getHeader("Authorization"),
                req.getHeader("WWW-Authenticate"));

        if(authStr != null && authStr.startsWith("Basic")) {
            // authStr: Basic base64credentials
            String base64Credentials = authStr.substring("Basic".length()).trim();

            // credentials = username:password
            String credentials = new String(DatatypeConverter.parseBase64Binary(base64Credentials));
            final String[] values = credentials.split(":", 2);

            if(values.length == 2) {
                String username = values[0];
                String password = values[1];
                //char[] password = values[1].toCharArray();

                result = new UsernamePasswordCredentials(username, password);
            } else {
                throw new RuntimeException("Invalid header - got: " + Arrays.asList(values));
            }
        }

        return result;
    }
}