James Moger
2012-10-13 c658df9e87d65b08d5482cf04489cb0532ff83dd
src/com/gitblit/GitServlet.java
@@ -15,10 +15,55 @@
 */
package com.gitblit;
import groovy.lang.Binding;
import groovy.util.GroovyScriptEngine;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.text.MessageFormat;
import java.util.Collection;
import java.util.Enumeration;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import org.eclipse.jgit.http.server.resolver.DefaultReceivePackFactory;
import org.eclipse.jgit.lib.PersonIdent;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.transport.PostReceiveHook;
import org.eclipse.jgit.transport.PreReceiveHook;
import org.eclipse.jgit.transport.ReceiveCommand;
import org.eclipse.jgit.transport.ReceiveCommand.Result;
import org.eclipse.jgit.transport.ReceivePack;
import org.eclipse.jgit.transport.resolver.ServiceNotAuthorizedException;
import org.eclipse.jgit.transport.resolver.ServiceNotEnabledException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.gitblit.Constants.AccessRestrictionType;
import com.gitblit.models.RepositoryModel;
import com.gitblit.models.UserModel;
import com.gitblit.utils.ClientLogger;
import com.gitblit.utils.HttpUtils;
import com.gitblit.utils.JGitUtils;
import com.gitblit.utils.StringUtils;
/**
 * The GitServlet exists to force configuration of the JGit GitServlet based on
 * the Gitblit settings from either gitblit.properties or from context
 * parameters in the web.xml file.
 *
 * It also implements and registers the Groovy hook mechanism.
 * 
 * Access to this servlet is protected by the GitFilter.
 * 
@@ -29,16 +74,360 @@
   private static final long serialVersionUID = 1L;
   /**
    * Configure the servlet from Gitblit's configuration.
    */
   private GroovyScriptEngine gse;
   private File groovyDir;
   @Override
   public String getInitParameter(String name) {
      if (name.equals("base-path")) {
         return GitBlit.getRepositoriesFolder().getAbsolutePath();
      } else if (name.equals("export-all")) {
         return "1";
   public void init(ServletConfig config) throws ServletException {
      groovyDir = GitBlit.getGroovyScriptsFolder();
      try {
         // set Grape root
         File grapeRoot = new File(GitBlit.getString(Keys.groovy.grapeFolder, "groovy/grape")).getAbsoluteFile();
         grapeRoot.mkdirs();
         System.setProperty("grape.root", grapeRoot.getAbsolutePath());
         gse = new GroovyScriptEngine(groovyDir.getAbsolutePath());
      } catch (IOException e) {
         throw new ServletException("Failed to instantiate Groovy Script Engine!", e);
      }
      return super.getInitParameter(name);
      // set the Gitblit receive hook
      setReceivePackFactory(new DefaultReceivePackFactory() {
         @Override
         public ReceivePack create(HttpServletRequest req, Repository db)
               throws ServiceNotEnabledException, ServiceNotAuthorizedException {
            // determine repository name from request
            String repositoryName = req.getPathInfo().substring(1);
            repositoryName = GitFilter.getRepositoryName(repositoryName);
            GitblitReceiveHook hook = new GitblitReceiveHook();
            hook.repositoryName = repositoryName;
            hook.gitblitUrl = HttpUtils.getGitblitURL(req);
            ReceivePack rp = super.create(req, db);
            rp.setPreReceiveHook(hook);
            rp.setPostReceiveHook(hook);
            // determine pushing user
            PersonIdent person = rp.getRefLogIdent();
            UserModel user = GitBlit.self().getUserModel(person.getName());
            if (user == null) {
               // anonymous push, create a temporary usermodel
               user = new UserModel(person.getName());
            }
            // enforce advanced ref permissions
            RepositoryModel repository = GitBlit.self().getRepositoryModel(repositoryName);
            rp.setAllowCreates(user.canCreateRef(repository));
            rp.setAllowDeletes(user.canDeleteRef(repository));
            rp.setAllowNonFastForwards(user.canRewindRef(repository));
            return rp;
         }
      });
      super.init(new GitblitServletConfig(config));
   }
   /**
    * Transitional wrapper class to configure the JGit 1.2 GitFilter. This
    * GitServlet will probably be replaced by a GitFilter so that Gitblit can
    * serve Git repositories on the root URL and not a /git sub-url.
    *
    * @author James Moger
    *
    */
   private class GitblitServletConfig implements ServletConfig {
      final ServletConfig config;
      GitblitServletConfig(ServletConfig config) {
         this.config = config;
      }
      @Override
      public String getServletName() {
         return config.getServletName();
      }
      @Override
      public ServletContext getServletContext() {
         return config.getServletContext();
      }
      @Override
      public String getInitParameter(String name) {
         if (name.equals("base-path")) {
            return GitBlit.getRepositoriesFolder().getAbsolutePath();
         } else if (name.equals("export-all")) {
            return "1";
         }
         return config.getInitParameter(name);
      }
      @Override
      public Enumeration<String> getInitParameterNames() {
         return config.getInitParameterNames();
      }
   }
   /**
    * The Gitblit receive hook allows for special processing on push events.
    * That might include rejecting writes to specific branches or executing a
    * script.
    *
    * @author James Moger
    *
    */
   private class GitblitReceiveHook implements PreReceiveHook, PostReceiveHook {
      protected final Logger logger = LoggerFactory.getLogger(GitblitReceiveHook.class);
      protected String repositoryName;
      protected String gitblitUrl;
      /**
       * Instrumentation point where the incoming push event has been parsed,
       * validated, objects created BUT refs have not been updated. You might
       * use this to enforce a branch-write permissions model.
       */
      @Override
      public void onPreReceive(ReceivePack rp, Collection<ReceiveCommand> commands) {
         RepositoryModel repository = GitBlit.self().getRepositoryModel(repositoryName);
         UserModel user = getUserModel(rp);
         if (repository.accessRestriction.atLeast(AccessRestrictionType.PUSH) && repository.verifyCommitter) {
            if (StringUtils.isEmpty(user.emailAddress)) {
               // emit warning if user does not have an email address
               logger.warn(MessageFormat.format("Consider setting an email address for {0} ({1}) to improve committer verification.", user.getDisplayName(), user.username));
            }
            // Optionally enforce that the committer of the left parent chain
            // match the account being used to push the commits.
            //
            // This requires all merge commits are executed with the "--no-ff"
            // option to force a merge commit even if fast-forward is possible.
            // This ensures that the chain of left parents has the commit
            // identity of the merging user.
            for (ReceiveCommand cmd : commands) {
               try {
                  List<RevCommit> commits = JGitUtils.getRevLog(rp.getRepository(), cmd.getOldId().name(), cmd.getNewId().name());
                  for (RevCommit commit : commits) {
                     PersonIdent committer = commit.getCommitterIdent();
                     if (!user.is(committer.getName(), committer.getEmailAddress())) {
                        String reason;
                        if (StringUtils.isEmpty(user.emailAddress)) {
                           // account does not have en email address
                           reason = MessageFormat.format("{0} by {1} <{2}> was not committed by {3} ({4})", commit.getId().name(), committer.getName(), StringUtils.isEmpty(committer.getEmailAddress()) ? "?":committer.getEmailAddress(), user.getDisplayName(), user.username);
                        } else {
                           // account has an email address
                           reason = MessageFormat.format("{0} by {1} <{2}> was not committed by {3} ({4}) <{5}>", commit.getId().name(), committer.getName(), StringUtils.isEmpty(committer.getEmailAddress()) ? "?":committer.getEmailAddress(), user.getDisplayName(), user.username, user.emailAddress);
                        }
                        cmd.setResult(Result.REJECTED_OTHER_REASON, reason);
                        break;
                     }
                  }
               } catch (Exception e) {
                  logger.error("Failed to verify commits were made by pushing user", e);
               }
            }
         }
         Set<String> scripts = new LinkedHashSet<String>();
         scripts.addAll(GitBlit.self().getPreReceiveScriptsInherited(repository));
         scripts.addAll(repository.preReceiveScripts);
         runGroovy(repository, user, commands, rp, scripts);
         for (ReceiveCommand cmd : commands) {
            if (!Result.NOT_ATTEMPTED.equals(cmd.getResult())) {
               logger.warn(MessageFormat.format("{0} {1} because \"{2}\"", cmd.getNewId()
                     .getName(), cmd.getResult(), cmd.getMessage()));
            }
         }
         // Experimental
         // runNativeScript(rp, "hooks/pre-receive", commands);
      }
      /**
       * Instrumentation point where the incoming push has been applied to the
       * repository. This is the point where we would trigger a Jenkins build
       * or send an email.
       */
      @Override
      public void onPostReceive(ReceivePack rp, Collection<ReceiveCommand> commands) {
         if (commands.size() == 0) {
            logger.info("skipping post-receive hooks, no refs created, updated, or removed");
            return;
         }
         RepositoryModel repository = GitBlit.self().getRepositoryModel(repositoryName);
         Set<String> scripts = new LinkedHashSet<String>();
         scripts.addAll(GitBlit.self().getPostReceiveScriptsInherited(repository));
         scripts.addAll(repository.postReceiveScripts);
         UserModel user = getUserModel(rp);
         runGroovy(repository, user, commands, rp, scripts);
         for (ReceiveCommand cmd : commands) {
            if (Result.OK.equals(cmd.getResult())) {
               // add some logging for important ref changes
               switch (cmd.getType()) {
               case DELETE:
                  logger.info(MessageFormat.format("{0} DELETED {1} in {2} ({3})", user.username, cmd.getRefName(), repository.name, cmd.getOldId().name()));
                  break;
               case CREATE:
                  logger.info(MessageFormat.format("{0} CREATED {1} in {2}", user.username, cmd.getRefName(), repository.name));
                  break;
               case UPDATE_NONFASTFORWARD:
                  logger.info(MessageFormat.format("{0} UPDATED NON-FAST-FORWARD {1} in {2} (from {3} to {4})", user.username, cmd.getRefName(), repository.name, cmd.getOldId().name(), cmd.getNewId().name()));
                  break;
               default:
                  break;
               }
            }
         }
         // Experimental
         // runNativeScript(rp, "hooks/post-receive", commands);
      }
      /**
       * Returns the UserModel for the user pushing the changes.
       *
       * @param rp
       * @return a UserModel
       */
      protected UserModel getUserModel(ReceivePack rp) {
         PersonIdent person = rp.getRefLogIdent();
         UserModel user = GitBlit.self().getUserModel(person.getName());
         if (user == null) {
            // anonymous push, create a temporary usermodel
            user = new UserModel(person.getName());
            user.isAuthenticated = false;
         }
         return user;
      }
      /**
       * Runs the specified Groovy hook scripts.
       *
       * @param repository
       * @param user
       * @param commands
       * @param scripts
       */
      protected void runGroovy(RepositoryModel repository, UserModel user,
            Collection<ReceiveCommand> commands, ReceivePack rp, Set<String> scripts) {
         if (scripts == null || scripts.size() == 0) {
            // no Groovy scripts to execute
            return;
         }
         Binding binding = new Binding();
         binding.setVariable("gitblit", GitBlit.self());
         binding.setVariable("repository", repository);
         binding.setVariable("receivePack", rp);
         binding.setVariable("user", user);
         binding.setVariable("commands", commands);
         binding.setVariable("url", gitblitUrl);
         binding.setVariable("logger", logger);
         binding.setVariable("clientLogger", new ClientLogger(rp));
         for (String script : scripts) {
            if (StringUtils.isEmpty(script)) {
               continue;
            }
            // allow script to be specified without .groovy extension
            // this is easier to read in the settings
            File file = new File(groovyDir, script);
            if (!file.exists() && !script.toLowerCase().endsWith(".groovy")) {
               file = new File(groovyDir, script + ".groovy");
               if (file.exists()) {
                  script = file.getName();
               }
            }
            try {
               Object result = gse.run(script, binding);
               if (result instanceof Boolean) {
                  if (!((Boolean) result)) {
                     logger.error(MessageFormat.format(
                           "Groovy script {0} has failed!  Hook scripts aborted.", script));
                     break;
                  }
               }
            } catch (Exception e) {
               logger.error(
                     MessageFormat.format("Failed to execute Groovy script {0}", script), e);
            }
         }
      }
      /**
       * Runs the native push hook script.
       *
       * http://book.git-scm.com/5_git_hooks.html
       * http://longair.net/blog/2011/04/09/missing-git-hooks-documentation/
       *
       * @param rp
       * @param script
       * @param commands
       */
      @SuppressWarnings("unused")
      protected void runNativeScript(ReceivePack rp, String script,
            Collection<ReceiveCommand> commands) {
         Repository repository = rp.getRepository();
         File scriptFile = new File(repository.getDirectory(), script);
         int resultCode = 0;
         if (scriptFile.exists()) {
            try {
               logger.debug("executing " + scriptFile);
               Process process = Runtime.getRuntime().exec(scriptFile.getAbsolutePath(), null,
                     repository.getDirectory());
               BufferedReader reader = new BufferedReader(new InputStreamReader(
                     process.getInputStream()));
               BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
                     process.getOutputStream()));
               for (ReceiveCommand command : commands) {
                  switch (command.getType()) {
                  case UPDATE:
                     // updating a ref
                     writer.append(MessageFormat.format("{0} {1} {2}\n", command.getOldId()
                           .getName(), command.getNewId().getName(), command.getRefName()));
                     break;
                  case CREATE:
                     // new ref
                     // oldrev hard-coded to 40? weird.
                     writer.append(MessageFormat.format("40 {0} {1}\n", command.getNewId()
                           .getName(), command.getRefName()));
                     break;
                  }
               }
               resultCode = process.waitFor();
               // read and buffer stdin
               // this is supposed to be piped back to the git client.
               // not sure how to do that right now.
               StringBuilder sb = new StringBuilder();
               String line = null;
               while ((line = reader.readLine()) != null) {
                  sb.append(line).append('\n');
               }
               logger.debug(sb.toString());
            } catch (Throwable e) {
               resultCode = -1;
               logger.error(
                     MessageFormat.format("Failed to execute {0}",
                           scriptFile.getAbsolutePath()), e);
            }
         }
         // reject push
         if (resultCode != 0) {
            for (ReceiveCommand command : commands) {
               command.setResult(Result.REJECTED_OTHER_REASON, MessageFormat.format(
                     "Native script {0} rejected push or failed",
                     scriptFile.getAbsolutePath()));
            }
         }
      }
   }
}