Minor refactoring of user/team checksumming

James Moger

2015-03-07 45ed92bd767e9e88d70c14d81e8bbb7acd2e5fe2

Minor refactoring of user/team checksumming

 src/main/java/com/gitblit/auth/AuthenticationProvider.java

@@ -15,13 +15,8 @@
 */
package com.gitblit.auth;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@@ -33,6 +28,7 @@
import com.gitblit.models.TeamModel;
import com.gitblit.models.UserModel;
import com.gitblit.utils.ArrayUtils;
import com.gitblit.utils.DeepCopier;
import com.gitblit.utils.StringUtils;

public abstract class AuthenticationProvider {
@@ -83,69 +79,35 @@
        }
    }

    /**
     * Utility method to calculate the checksum of an object.
     * @param sourceObject The object from which to establish the checksum.
     * @return The checksum
     * @throws IOException
     * @throws NoSuchAlgorithmException
     */
    private BigInteger checksum(Object sourceObject) throws IOException, NoSuchAlgorithmException {

        if (sourceObject == null) {
          return BigInteger.ZERO;   
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(baos);
        oos.writeObject(sourceObject);
        oos.close();

        MessageDigest m = MessageDigest.getInstance("SHA1");
        m.update(baos.toByteArray());

        return new BigInteger(1, m.digest());
    }
	
    protected void updateUser(UserModel userModel) {
        final UserModel userLocalDB = userManager.getUserModel(userModel.getName());
        try {

            // Establish the checksum of the current version of the user
            final BigInteger userCurrentCheck = checksum(userModel);
        final BigInteger userCurrentCheck = DeepCopier.checksum(userModel);

            // Establish the checksum of the stored version of the user
            final BigInteger userLocalDBcheck = checksum(userLocalDB);
        final BigInteger userLocalDBcheck = DeepCopier.checksum(userLocalDB);

            // Compare the checksums
            if (!userCurrentCheck.equals(userLocalDBcheck))
            {
        if (!userCurrentCheck.equals(userLocalDBcheck)) {
                // If mismatch, save the new instance.
                userManager.updateUserModel(userModel);
            }
        } catch (NoSuchAlgorithmException | IOException e) {
            // Trace any potential error.
            if (logger.isErrorEnabled()) {
                logger.error(e.getMessage());
            }
        }
    }

    protected void updateTeam(TeamModel teamModel) {
        final TeamModel teamLocalDB = userManager.getTeamModel(teamModel.name);
        try {

            // Establish the checksum of the current version of the team
            final BigInteger teamCurrentCheck = checksum(teamModel);
        final BigInteger teamCurrentCheck = DeepCopier.checksum(teamModel);

            // Establish the checksum of the stored version of the team
            final BigInteger teamLocalDBcheck = checksum(teamLocalDB);
        final BigInteger teamLocalDBcheck = DeepCopier.checksum(teamLocalDB);

            // Compare the checksums
            if (!teamCurrentCheck.equals(teamLocalDBcheck))
            {
        if (!teamCurrentCheck.equals(teamLocalDBcheck)) {
                // If mismatch, save the new instance.
                userManager.updateTeamModel(teamModel);
            }
        } catch (NoSuchAlgorithmException | IOException e) {
            // Trace any potential error.
            if (logger.isErrorEnabled()) {
                logger.error(e.getMessage());
            }
        }
    }


 src/main/java/com/gitblit/utils/DeepCopier.java

@@ -23,10 +23,43 @@
import java.io.ObjectOutputStream;

import java.io.PipedInputStream;

import java.io.PipedOutputStream;

import java.math.BigInteger;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;



public class DeepCopier {



    /**

     * Utility method to calculate the checksum of an object.

     * @param sourceObject The object from which to establish the checksum.

     * @return The checksum

     * @throws IOException

     */

    public static BigInteger checksum(Object sourceObject) {



        if (sourceObject == null) {

          return BigInteger.ZERO;

        }



        try {

            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            ObjectOutputStream oos = new ObjectOutputStream(baos);

            oos.writeObject(sourceObject);

            oos.close();



            MessageDigest m = MessageDigest.getInstance("SHA-1");

            m.update(baos.toByteArray());

            return new BigInteger(1, m.digest());

        } catch (IOException e) {

            throw new RuntimeException(e);

        } catch (NoSuchAlgorithmException e) {

            // impossible

        }



        return BigInteger.ZERO;

    }



    /**

     * Produce a deep copy of the given object. Serializes the entire object to

     * a byte array in memory. Recommended for relatively small objects.

     */