Add a new git/hooks role

This will be needed to migrate Dist Git from puppet to ansible.

6 files changed, 1400 insertions, 0 deletions

diff --git a/roles/git/hooks/files/git.py b/roles/git/hooks/files/git.py
new file mode 100644
index 000000000..72adff1f7
--- /dev/null
+++ b/roles/git/hooks/files/git.py
@@ -0,0 +1,211 @@
+# Utility functions for git
+#
+# Copyright (C) 2008  Owen Taylor
+# Copyright (C) 2009  Red Hat, Inc
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, If not, see
+# http://www.gnu.org/licenses/.
+#
+# (These are adapted from git-bz)
+
+import os
+import re
+from subprocess import Popen, PIPE
+import sys
+
+from util import die
+
+# Clone of subprocess.CalledProcessError (not in Python 2.4)
+class CalledProcessError(Exception):
+    def __init__(self, returncode, cmd):
+        self.returncode = returncode
+        self.cmd = cmd
+
+    def __str__(self):
+        return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
+
+NULL_REVISION = "0000000000000000000000000000000000000000"
+
+# Run a git command
+#    Non-keyword arguments are passed verbatim as command line arguments
+#    Keyword arguments are turned into command line options
+#       <name>=True => --<name>
+#       <name>='<str>' => --<name>=<str>
+#    Special keyword arguments:
+#       _quiet: Discard all output even if an error occurs
+#       _interactive: Don't capture stdout and stderr
+#       _input=<str>: Feed <str> to stdinin of the command
+#       _outfile=<file): Use <file> as the output file descriptor
+#       _split_lines: Return an array with one string per returned line
+#
+def git_run(command, *args, **kwargs):
+    to_run = ['git', command.replace("_", "-")]
+
+    interactive = False
+    quiet = False
+    input = None
+    interactive = False
+    outfile = None
+    do_split_lines = False
+    for (k,v) in kwargs.iteritems():
+        if k == '_quiet':
+            quiet = True
+        elif k == '_interactive':
+            interactive = True
+        elif k == '_input':
+            input = v
+        elif k == '_outfile':
+            outfile = v
+        elif k == '_split_lines':
+            do_split_lines = True
+        elif v is True:
+            if len(k) == 1:
+                to_run.append("-" + k)
+            else:
+                to_run.append("--" + k.replace("_", "-"))
+        else:
+            to_run.append("--" + k.replace("_", "-") + "=" + v)
+
+    to_run.extend(args)
+
+    if outfile:
+        stdout = outfile
+    else:
+        if interactive:
+            stdout = None
+        else:
+            stdout = PIPE
+
+    if interactive:
+        stderr = None
+    else:
+        stderr = PIPE
+
+    if input != None:
+        stdin = PIPE
+    else:
+        stdin = None
+
+    process = Popen(to_run,
+                    stdout=stdout, stderr=stderr, stdin=stdin)
+    output, error = process.communicate(input)
+    if process.returncode != 0:
+        if not quiet and not interactive:
+            print >>sys.stderr, error,
+            print output,
+        raise CalledProcessError(process.returncode, " ".join(to_run))
+
+    if interactive or outfile:
+        return None
+    else:
+        if do_split_lines:
+            return output.strip().splitlines()
+        else:
+            return output.strip()
+
+# Wrapper to allow us to do git.<command>(...) instead of git_run()
+class Git:
+    def __getattr__(self, command):
+        def f(*args, **kwargs):
+            return git_run(command, *args, **kwargs)
+        return f
+
+git = Git()
+
+class GitCommit:
+    def __init__(self, id, subject):
+        self.id = id
+        self.subject = subject
+
+# Takes argument like 'git.rev_list()' and returns a list of commit objects
+def rev_list_commits(*args, **kwargs):
+    kwargs_copy = dict(kwargs)
+    kwargs_copy['pretty'] = 'format:%s'
+    kwargs_copy['_split_lines'] = True
+    lines = git.rev_list(*args, **kwargs_copy)
+    if (len(lines) % 2 != 0):
+        raise RuntimeException("git rev-list didn't return an even number of lines")
+
+    result = []
+    for i in xrange(0, len(lines), 2):
+        m = re.match("commit\s+([A-Fa-f0-9]+)", lines[i])
+        if not m:
+            raise RuntimeException("Can't parse commit it '%s'", lines[i])
+        commit_id = m.group(1)
+        subject = lines[i + 1]
+        result.append(GitCommit(commit_id, subject))
+
+    return result
+
+# Loads a single commit object by ID
+def load_commit(commit_id):
+    return rev_list_commits(commit_id + "^!")[0]
+
+# Return True if the commit has multiple parents
+def commit_is_merge(commit):
+    if isinstance(commit, basestring):
+        commit = load_commit(commit)
+
+    parent_count = 0
+    for line in git.cat_file("commit", commit.id, _split_lines=True):
+        if line == "":
+            break
+        if line.startswith("parent "):
+            parent_count += 1
+
+    return parent_count > 1
+
+# Return a short one-line summary of the commit
+def commit_oneline(commit):
+    if isinstance(commit, basestring):
+        commit = load_commit(commit)
+
+    return commit.id[0:7]+"... " + commit.subject[0:59]
+
+# Return the directory name with .git stripped as a short identifier
+# for the module
+def get_module_name():
+    try:
+        git_dir = git.rev_parse(git_dir=True, _quiet=True)
+    except CalledProcessError:
+        die("GIT_DIR not set")
+
+    # Use the directory name with .git stripped as a short identifier
+    absdir = os.path.abspath(git_dir)
+    if absdir.endswith(os.sep + '.git'):
+        absdir = os.path.dirname(absdir)
+    projectshort = os.path.basename(absdir)
+    if projectshort.endswith(".git"):
+        projectshort = projectshort[:-4]
+
+    return projectshort
+
+# Return the project description or '' if it is 'Unnamed repository;'
+def get_project_description():
+    try:
+        git_dir = git.rev_parse(git_dir=True, _quiet=True)
+    except CalledProcessError:
+        die("GIT_DIR not set")
+
+    projectdesc = ''
+    description = os.path.join(git_dir, 'description')
+    if os.path.exists(description):
+        try:
+            projectdesc = open(description).read().strip()
+        except:
+            pass
+    if projectdesc.startswith('Unnamed repository;'):
+        projectdesc = ''
+
+    return projectdesc
diff --git a/roles/git/hooks/files/gnome-post-receive-email b/roles/git/hooks/files/gnome-post-receive-email
new file mode 100644
index 000000000..4c5cd619b
--- /dev/null
+++ b/roles/git/hooks/files/gnome-post-receive-email
@@ -0,0 +1,941 @@
+#!/usr/bin/python
+#
+# gnome-post-receive-email - Post receive email hook for the GNOME Git repository
+#
+# Copyright (C) 2008  Owen Taylor
+# Copyright (C) 2009  Red Hat, Inc
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, If not, see
+# http://www.gnu.org/licenses/.
+#
+# About
+# =====
+# This script is used to generate mail to commits-list@gnome.org when change
+# are pushed to the GNOME git repository. It accepts input in the form of
+# a Git post-receive hook, and generates appropriate emails.
+#
+# The attempt here is to provide a maximimally useful and robust output
+# with as little clutter as possible.
+#
+
+import re
+import os
+import pwd
+import sys
+from email.header import Header
+from socket import gethostname
+
+from kitchen.text.converters import to_bytes, to_unicode
+from kitchen.text.misc import byte_string_valid_encoding
+
+script_path = os.path.realpath(os.path.abspath(sys.argv[0]))
+script_dir = os.path.dirname(script_path)
+
+sys.path.insert(0, script_dir)
+
+from git import *
+from util import die, strip_string as s, start_email, end_email
+
+# When we put a git subject into the Subject: line, where to truncate
+SUBJECT_MAX_SUBJECT_CHARS = 100
+
+CREATE = 0
+UPDATE = 1
+DELETE = 2
+INVALID_TAG = 3
+
+# Short name for project
+projectshort = None
+
+# Project description
+projectdesc = None
+
+# Human readable name for user, might be None
+user_fullname = None
+
+# Who gets the emails
+recipients = None
+
+# What domain the emails are from
+maildomain = None
+
+# short diff output only
+mailshortdiff = False
+
+# map of ref_name => Change object; this is used when computing whether
+# we've previously generated a detailed diff for a commit in the push
+all_changes = {}
+processed_changes = {}
+
+class RefChange(object):
+    def __init__(self, refname, oldrev, newrev):
+        self.refname = refname
+        self.oldrev = oldrev
+        self.newrev = newrev
+
+        if oldrev == None and newrev != None:
+            self.change_type = CREATE
+        elif oldrev != None and newrev == None:
+            self.change_type = DELETE
+        elif oldrev != None and newrev != None:
+            self.change_type = UPDATE
+        else:
+            self.change_type = INVALID_TAG
+
+        m = re.match(r"refs/[^/]*/(.*)", refname)
+        if m:
+            self.short_refname = m.group(1)
+        else:
+            self.short_refname = refname
+
+    # Do any setup before sending email. The __init__ function should generally
+    # just record the parameters passed in and not do git work. (The main reason
+    # for the split is to let the prepare stage do different things based on
+    # whether other ref updates have been processed or not.)
+    def prepare(self):
+        pass
+
+    # Whether we should generate the normal 'main' email. For simple branch
+    # updates we only generate 'extra' emails
+    def get_needs_main_email(self):
+        return True
+
+    # The XXX in [projectname/XXX], usually a branch
+    def get_project_extra(self):
+        return None
+
+    # Return the subject for the main email, without the leading [projectname]
+    def get_subject(self):
+        raise NotImplementedError()
+
+    # Write the body of the main email to the given file object
+    def generate_body(self, out):
+        raise NotImplementedError()
+
+    def generate_header(self, out, subject, include_revs=True, oldrev=None, newrev=None):
+        user = os.environ['USER']
+        if user_fullname:
+            from_address = "%s <%s@%s>" % (user_fullname, user, maildomain)
+        else:
+            from_address = "%s@%s" % (user, maildomain)
+
+        if not byte_string_valid_encoding(to_bytes(subject), 'ascii'):
+            # non-ascii chars
+            subject = Header(to_bytes(to_unicode(subject)), 'utf-8').encode()
+
+        print >>out, s("""
+To: %(recipients)s
+From: %(from_address)s
+Subject: %(subject)s
+MIME-Version: 1.0
+Content-Transfer-Encoding: 8bit
+Content-Type: text/plain; charset="utf-8"
+Keywords: %(projectshort)s
+X-Project: %(projectdesc)s
+X-Git-Refname: %(refname)s
+""") % {
+            'recipients': to_bytes(recipients, errors='strict'),
+            'from_address': to_bytes(from_address, errors='strict'),
+            'subject': subject,
+            'projectshort': to_bytes(projectshort),
+            'projectdesc': to_bytes(projectdesc),
+            'refname': to_bytes(self.refname)
+       }
+
+        if include_revs:
+            if oldrev:
+                oldrev = oldrev
+            else:
+                oldrev = NULL_REVISION
+            if newrev:
+                newrev = newrev
+            else:
+                newrev = NULL_REVISION
+
+            print >>out, s("""
+X-Git-Oldrev: %(oldrev)s
+X-Git-Newrev: %(newrev)s
+""") % {
+            'oldrev': to_bytes(oldrev),
+            'newrev': to_bytes(newrev),
+       }
+
+        # Trailing newline to signal the end of the header
+        print >>out
+
+    def send_main_email(self):
+        if not self.get_needs_main_email():
+            return
+
+        extra = self.get_project_extra()
+        if extra:
+            extra = "/" + extra
+        else:
+            extra = ""
+        subject = "[" + projectshort + extra + "] " + self.get_subject()
+
+        email_out = start_email()
+
+        self.generate_header(email_out, subject, include_revs=True, oldrev=self.oldrev, newrev=self.newrev)
+        self.generate_body(email_out)
+
+        end_email()
+
+    # Allow multiple emails to be sent - used for branch updates
+    def send_extra_emails(self):
+        pass
+
+    def send_emails(self):
+        self.send_main_email()
+        self.send_extra_emails()
+
+# ========================
+
+# Common baseclass for BranchCreation and BranchUpdate (but not BranchDeletion)
+class BranchChange(RefChange):
+    def __init__(self, *args):
+        RefChange.__init__(self, *args)
+
+    def prepare(self):
+        # We need to figure out what commits are referenced in this commit thta
+        # weren't previously referenced in the repository by another branch.
+        # "Previously" here means either before this push, or by branch updates
+        # we've already done in this push. These are the commits we'll send
+        # out individual mails for.
+        #
+        # Note that "Before this push" can't be gotten exactly right since an
+        # push is only atomic per-branch and there is no locking across branches.
+        # But new commits will always show up in a cover mail in any case; even
+        # someone who maliciously is trying to fool us can't hide all trace.
+
+        # Ordering matters here, so we can't rely on kwargs
+        branches = git.rev_parse('--symbolic-full-name', '--branches', _split_lines=True)
+        detailed_commit_args = [ self.newrev ]
+
+        for branch in branches:
+            if branch == self.refname:
+                # For this branch, exclude commits before 'oldrev'
+                if self.change_type != CREATE:
+                    detailed_commit_args.append("^" + self.oldrev)
+            elif branch in all_changes and not branch in processed_changes:
+                # For branches that were updated in this push but we haven't processed
+                # yet, exclude commits before their old revisions
+                detailed_commit_args.append("^" + all_changes[branch].oldrev)
+            else:
+                # Exclude commits that are ancestors of all other branches
+                detailed_commit_args.append("^" + branch)
+
+        detailed_commits = git.rev_list(*detailed_commit_args).splitlines()
+
+        self.detailed_commits = set()
+        for id in detailed_commits:
+            self.detailed_commits.add(id)
+
+        # Find the commits that were added and removed, reverse() to get
+        # chronological order
+        if self.change_type == CREATE:
+            # If someone creates a branch of GTK+, we don't want to list (or even walk through)
+            # all 30,000 commits in the history as "new commits" on the branch. So we start
+            # the commit listing from the first commit we are going to send a mail out about.
+            #
+            # This does mean that if someone creates a branch, merges it, and then pushes
+            # both the branch and what was merged into at once, then the resulting mails will
+            # be a bit strange (depending on ordering) - the mail for the creation of the
+            # branch may look like it was created in the finished state because all the commits
+            # have been already mailed out for the other branch. I don't think this is a big
+            # problem, and the best way to fix it would be to sort the ref updates so that the
+            # branch creation was processed first.
+            #
+            if len(detailed_commits) > 0:
+                # Verify parent of first detailed commit is valid. On initial push, it is not.
+                parent = detailed_commits[-1] + "^"
+                try:
+                    validref = git.rev_parse(parent, _quiet=True)
+                except CalledProcessError, error:
+                    self.added_commits = []
+                else:
+                    self.added_commits = rev_list_commits(parent + ".." + self.newrev)
+                    self.added_commits.reverse()
+            else:
+                self.added_commits = []
+            self.removed_commits = []
+        else:
+            self.added_commits = rev_list_commits(self.oldrev + ".." + self.newrev)
+            self.added_commits.reverse()
+            self.removed_commits = rev_list_commits(self.newrev + ".." + self.oldrev)
+            self.removed_commits.reverse()
+
+        # In some cases we'll send a cover email that describes the overall
+        # change to the branch before ending individual mails for commits. In other
+        # cases, we just send the individual emails. We generate a cover mail:
+        #
+        # - If it's a branch creation
+        # - If it's not a fast forward
+        # - If there are any merge commits
+        # - If there are any commits we won't send separately (already in repo)
+
+        have_merge_commits = False
+        for commit in self.added_commits:
+            if commit_is_merge(commit):
+                have_merge_commits = True
+
+        self.needs_cover_email = (self.change_type == CREATE or
+                                  len(self.removed_commits) > 0 or
+                                  have_merge_commits or
+                                  len(self.detailed_commits) < len(self.added_commits))
+
+    def get_needs_main_email(self):
+        return self.needs_cover_email
+
+    # A prefix for the cover letter summary with the number of added commits
+    def get_count_string(self):
+        if len(self.added_commits) > 1:
+            return "(%d commits) " % len(self.added_commits)
+        else:
+            return ""
+
+    # Generate a short listing for a series of commits
+    # show_details - whether we should mark commit where we aren't going to send
+    # a detailed email. (Set the False when listing removed commits)
+    def generate_commit_summary(self, out, commits, show_details=True):
+        detail_note = False
+        for commit in commits:
+            if show_details and not commit.id in self.detailed_commits:
+                detail = " (*)"
+                detail_note = True
+            else:
+                detail = ""
+            print >>out, "  %s%s" % (to_bytes(commit_oneline(commit)), to_bytes(detail))
+
+        if detail_note:
+            print >>out
+            print >>out, "(*) This commit already existed in another branch; no separate mail sent"
+
+    def send_extra_emails(self):
+        total = len(self.added_commits)
+
+        for i, commit in enumerate(self.added_commits):
+            if not commit.id in self.detailed_commits:
+                continue
+
+            email_out = start_email()
+
+            if self.short_refname == 'master':
+                branch = ""
+            else:
+                branch = "/" + self.short_refname
+
+            total = len(self.added_commits)
+            if total > 1 and self.needs_cover_email:
+                count_string = ": %(index)s/%(total)s" % {
+                    'index' : i + 1,
+                    'total' : total
+                }
+            else:
+                count_string = ""
+
+            subject = "[%(projectshort)s%(branch)s%(count_string)s] %(subject)s" % {
+                'projectshort' : projectshort,
+                'branch' : branch,
+                'count_string' : count_string,
+                'subject' : commit.subject[0:SUBJECT_MAX_SUBJECT_CHARS]
+                }
+
+            # If there is a cover email, it has the X-Git-OldRev/X-Git-NewRev in it
+            # for the total branch update. Without a cover email, we are conceptually
+            # breaking up the update into individual updates for each commit
+            if self.needs_cover_email:
+                self.generate_header(email_out, subject, include_revs=False)
+            else:
+                parent = git.rev_parse(commit.id + "^")
+                self.generate_header(email_out, subject,
+                                     include_revs=True,
+                                     oldrev=parent, newrev=commit.id)
+
+            email_out.flush()
+            git.show(commit.id, M=True, stat=True, _outfile=email_out)
+            email_out.flush()
+            if not mailshortdiff:
+                git.show(commit.id, p=True, M=True, diff_filter="ACMRTUXB", pretty="format:---", _outfile=email_out)
+            end_email()
+
+class BranchCreation(BranchChange):
+    def get_subject(self):
+        return self.get_count_string() + "Created branch " + self.short_refname
+
+    def generate_body(self, out):
+        if len(self.added_commits) > 0:
+            print >>out, s("""
+The branch '%(short_refname)s' was created.
+
+Summary of new commits:
+
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+       }
+
+            self.generate_commit_summary(out, self.added_commits)
+        else:
+            print >>out, s("""
+The branch '%(short_refname)s' was created pointing to:
+
+ %(commit_oneline)s
+
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+            'commit_oneline': to_bytes(commit_oneline(self.newrev))
+       }
+
+class BranchUpdate(BranchChange):
+    def get_project_extra(self):
+        if len(self.removed_commits) > 0:
+            # In the non-fast-forward-case, the branch name is in the subject
+            return None
+        else:
+            if self.short_refname == 'master':
+                # Not saying 'master' all over the place reduces clutter
+                return None
+            else:
+                return self.short_refname
+
+    def get_subject(self):
+        if len(self.removed_commits) > 0:
+            return self.get_count_string() + "Non-fast-forward update to branch " + self.short_refname
+        else:
+            # We want something for useful for the subject than "Updates to branch spiffy-stuff".
+            # The common case where we have a cover-letter for a fast-forward branch
+            # update is a merge. So we try to get:
+            #
+            #  [myproject/spiffy-stuff] (18 commits) ...Merge branch master
+            #
+            last_commit = self.added_commits[-1]
+            if len(self.added_commits) > 1:
+                return self.get_count_string() + "..." + last_commit.subject[0:SUBJECT_MAX_SUBJECT_CHARS]
+            else:
+                # The ... indicates we are only showing one of many, don't need it for a single commit
+                return last_commit.subject[0:SUBJECT_MAX_SUBJECT_CHARS]
+
+    def generate_body_normal(self, out):
+        print >>out, s("""
+Summary of changes:
+
+""")
+
+        self.generate_commit_summary(out, self.added_commits)
+
+    def generate_body_non_fast_forward(self, out):
+        print >>out, s("""
+The branch '%(short_refname)s' was changed in a way that was not a fast-forward update.
+NOTE: This may cause problems for people pulling from the branch. For more information,
+please see:
+
+ http://live.gnome.org/Git/Help/NonFastForward
+
+Commits removed from the branch:
+
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+       }
+
+        self.generate_commit_summary(out, self.removed_commits, show_details=False)
+
+        print >>out, s("""
+
+Commits added to the branch:
+
+""")
+        self.generate_commit_summary(out, self.added_commits)
+
+    def generate_body(self, out):
+        if len(self.removed_commits) == 0:
+            self.generate_body_normal(out)
+        else:
+            self.generate_body_non_fast_forward(out)
+
+class BranchDeletion(RefChange):
+    def get_subject(self):
+        return "Deleted branch " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The branch '%(short_refname)s' was deleted.
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+       }
+
+# ========================
+
+class AnnotatedTagChange(RefChange):
+    def __init__(self, *args):
+        RefChange.__init__(self, *args)
+
+    def prepare(self):
+        # Resolve tag to commit
+        if self.oldrev:
+            self.old_commit_id = git.rev_parse(self.oldrev + "^{commit}")
+
+        if self.newrev:
+            self.parse_tag_object(self.newrev)
+        else:
+            self.parse_tag_object(self.oldrev)
+
+    # Parse information out of the tag object
+    def parse_tag_object(self, revision):
+        message_lines = []
+        in_message = False
+
+        # A bit of paranoia if we fail at parsing; better to make the failure
+        # visible than just silently skip Tagger:/Date:.
+        self.tagger = "unknown <unknown@example.com>"
+        self.date = "at an unknown time"
+
+        self.have_signature = False
+        for line in git.cat_file(revision, p=True, _split_lines=True):
+            if in_message:
+                # Nobody is going to verify the signature by extracting it
+                # from the email, so strip it, and remember that we saw it
+                # by saying 'signed tag'
+                if re.match(r'-----BEGIN PGP SIGNATURE-----', line):
+                    self.have_signature = True
+                    break
+                message_lines.append(line)
+            else:
+                if line.strip() == "":
+                    in_message = True
+                    continue
+                # I don't know what a more robust rule is for dividing the
+                # name and date, other than maybe looking explicitly for a
+                # RFC 822 date. This seems to work pretty well
+                m = re.match(r"tagger\s+([^>]*>)\s*(.*)", line)
+                if m:
+                    self.tagger = m.group(1)
+                    self.date = m.group(2)
+                    continue
+        self.message = "\n".join(["    " + line for line in message_lines])
+
+    # Outputs information about the new tag
+    def generate_tag_info(self, out):
+
+        print >>out, s("""
+Tagger: %(tagger)s
+Date: %(date)s
+
+%(message)s
+
+""") % {
+            'tagger': to_bytes(self.tagger),
+            'date': to_bytes(self.date),
+            'message': to_bytes(self.message),
+       }
+
+        # We take the creation of an annotated tag as being a "mini-release-announcement"
+        # and show a 'git shortlog' of the changes since the last tag that was an
+        # ancestor of the new tag.
+        last_tag = None
+        try:
+            # A bit of a hack to get that previous tag
+            last_tag = git.describe(self.newrev+"^", abbrev='0', _quiet=True)
+        except CalledProcessError:
+            # Assume that this means no older tag
+            pass
+
+        if last_tag:
+            revision_range = last_tag + ".." + self.newrev
+            print >>out, s("""
+Changes since the last tag '%(last_tag)s':
+
+""") % {
+                'last_tag': to_bytes(last_tag)
+      }
+        else:
+            revision_range = self.newrev
+            print >>out, s("""
+Changes:
+
+""")
+        out.write(to_bytes(git.shortlog(revision_range)))
+        out.write("\n")
+
+    def get_tag_type(self):
+        if self.have_signature:
+            return 'signed tag'
+        else:
+            return 'unsigned tag'
+
+class AnnotatedTagCreation(AnnotatedTagChange):
+    def get_subject(self):
+        return "Created tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The %(tag_type)s '%(short_refname)s' was created.
+
+""") % {
+            'tag_type': to_bytes(self.get_tag_type()),
+            'short_refname': to_bytes(self.short_refname),
+       }
+        self.generate_tag_info(out)
+
+class AnnotatedTagDeletion(AnnotatedTagChange):
+    def get_subject(self):
+        return "Deleted tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The %(tag_type)s '%(short_refname)s' was deleted. It previously pointed to:
+
+ %(old_commit_oneline)s
+""") % {
+            'tag_type': to_bytes(self.get_tag_type()),
+            'short_refname': to_bytes(self.short_refname),
+            'old_commit_oneline': to_bytes(commit_oneline(self.old_commit_id)),
+       }
+
+class AnnotatedTagUpdate(AnnotatedTagChange):
+    def get_subject(self):
+        return "Updated tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The tag '%(short_refname)s' was replaced with a new tag. It previously
+pointed to:
+
+ %(old_commit_oneline)s
+
+NOTE: People pulling from the repository will not get the new tag.
+For more information, please see:
+
+ http://live.gnome.org/Git/Help/TagUpdates
+
+New tag information:
+
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+            'old_commit_oneline': to_bytes(commit_oneline(self.old_commit_id)),
+       }
+        self.generate_tag_info(out)
+
+# ========================
+
+class LightweightTagCreation(RefChange):
+    def get_subject(self):
+        return "Created tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The lightweight tag '%(short_refname)s' was created pointing to:
+
+ %(commit_oneline)s
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+            'commit_oneline': to_bytes(commit_oneline(self.newrev))
+       }
+
+class LightweightTagDeletion(RefChange):
+    def get_subject(self):
+        return "Deleted tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The lighweight tag '%(short_refname)s' was deleted. It previously pointed to:
+
+ %(commit_oneline)s
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+            'commit_oneline': to_bytes(commit_oneline(self.oldrev)),
+       }
+
+class LightweightTagUpdate(RefChange):
+    def get_subject(self):
+        return "Updated tag " + self.short_refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The lightweight tag '%(short_refname)s' was updated to point to:
+
+ %(commit_oneline)s
+
+It previously pointed to:
+
+ %(old_commit_oneline)s
+
+NOTE: People pulling from the repository will not get the new tag.
+For more information, please see:
+
+ http://live.gnome.org/Git/Help/TagUpdates
+""") % {
+            'short_refname': to_bytes(self.short_refname),
+            'commit_oneline': to_bytes(commit_oneline(self.newrev)),
+            'old_commit_oneline': to_bytes(commit_oneline(self.oldrev)),
+       }
+
+# ========================
+
+class InvalidRefDeletion(RefChange):
+    def get_subject(self):
+        return "Deleted invalid ref " + self.refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The ref '%(refname)s' was deleted. It previously pointed nowhere.
+""") % {
+            'refname': to_bytes(self.refname),
+       }
+
+# ========================
+
+class MiscChange(RefChange):
+    def __init__(self, refname, oldrev, newrev, message):
+        RefChange.__init__(self, refname, oldrev, newrev)
+        self.message = message
+
+class MiscCreation(MiscChange):
+    def get_subject(self):
+        return "Unexpected: Created " + self.refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The ref '%(refname)s' was created pointing to:
+
+ %(newrev)s
+
+This is unexpected because:
+
+ %(message)s
+""") % {
+            'refname': to_bytes(self.refname),
+            'newrev': to_bytes(self.newrev),
+            'message': to_bytes(self.message),
+      }
+
+class MiscDeletion(MiscChange):
+    def get_subject(self):
+        return "Unexpected: Deleted " + self.refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The ref '%(refname)s' was deleted. It previously pointed to:
+
+ %(oldrev)s
+
+This is unexpected because:
+
+ %(message)s
+""") % {
+            'refname': to_bytes(self.refname),
+            'oldrev': to_bytes(self.oldrev),
+            'message': to_bytes(self.message),
+      }
+
+class MiscUpdate(MiscChange):
+    def get_subject(self):
+        return "Unexpected: Updated " + self.refname
+
+    def generate_body(self, out):
+        print >>out, s("""
+The ref '%(refname)s' was updated from:
+
+ %(newrev)s
+
+To:
+
+ %(oldrev)s
+
+This is unexpected because:
+
+ %(message)s
+""") % {
+            'refname': to_bytes(self.refname),
+            'oldrev': to_bytes(self.oldrev),
+            'newrev': to_bytes(self.newrev),
+            'message': to_bytes(self.message),
+      }
+
+# ========================
+
+def make_change(oldrev, newrev, refname):
+    refname = refname
+
+    # Canonicalize
+    oldrev = git.rev_parse(oldrev)
+    newrev = git.rev_parse(newrev)
+
+    # Replacing the null revision with None makes it easier for us to test
+    # in subsequent code
+
+    if re.match(r'^0+$', oldrev):
+        oldrev = None
+    else:
+        oldrev = oldrev
+
+    if re.match(r'^0+$', newrev):
+        newrev = None
+    else:
+        newrev = newrev
+
+    # Figure out what we are doing to the ref
+
+    if oldrev == None and newrev != None:
+        change_type = CREATE
+        target = newrev
+    elif oldrev != None and newrev == None:
+        change_type = DELETE
+        target = oldrev
+    elif oldrev != None and newrev != None:
+        change_type = UPDATE
+        target = newrev
+    else:
+        return InvalidRefDeletion(refname, oldrev, newrev)
+
+    object_type = git.cat_file(target, t=True)
+
+    # And then create the right type of change object
+
+    # Closing the arguments like this simplifies the following code
+    def make(cls, *args):
+        return cls(refname, oldrev, newrev, *args)
+
+    def make_misc_change(message):
+        if change_type == CREATE:
+            return make(MiscCreation, message)
+        elif change_type == DELETE:
+            return make(MiscDeletion, message)
+        else:
+            return make(MiscUpdate, message)
+
+    if re.match(r'^refs/tags/.*$', refname):
+        if object_type == 'commit':
+            if change_type == CREATE:
+                return make(LightweightTagCreation)
+            elif change_type == DELETE:
+                return make(LightweightTagDeletion)
+            else:
+                return make(LightweightTagUpdate)
+        elif object_type == 'tag':
+            if change_type == CREATE:
+                return make(AnnotatedTagCreation)
+            elif change_type == DELETE:
+                return make(AnnotatedTagDeletion)
+            else:
+                return make(AnnotatedTagUpdate)
+        else:
+            return make_misc_change("%s is not a commit or tag object" % target)
+    elif re.match(r'^refs/heads/.*$', refname):
+        if object_type == 'commit':
+            if change_type == CREATE:
+                return make(BranchCreation)
+            elif change_type == DELETE:
+                return make(BranchDeletion)
+            else:
+                return make(BranchUpdate)
+        else:
+            return make_misc_change("%s is not a commit object" % target)
+    elif re.match(r'^refs/remotes/.*$', refname):
+        return make_misc_change("'%s' is a tracking branch and doesn't belong on the server" % refname)
+    else:
+        return make_misc_change("'%s' is not in refs/heads/ or refs/tags/" % refname)
+
+def main():
+    global projectshort
+    global projectdesc
+    global user_fullname
+    global recipients
+    global maildomain
+    global mailshortdiff
+
+    # No emails for a repository in the process of being imported
+    git_dir = git.rev_parse(git_dir=True, _quiet=True)
+    if os.path.exists(os.path.join(git_dir, 'pending')):
+        return
+    
+    projectshort = get_module_name()
+    projectdesc = get_project_description()
+
+
+    try:
+        mailshortdiff=git.config("hooks.mailshortdiff", _quiet=True)
+    except CalledProcessError:
+        pass
+    
+    if isinstance(mailshortdiff, str) and mailshortdiff.lower() in ('true', 'yes', 'on', '1'):
+        mailshortdiff = True
+    else:
+        mailshortdiff = False
+
+    try:
+        recipients=git.config("hooks.mailinglist", _quiet=True)
+    except CalledProcessError:
+        pass
+        
+    if not recipients:
+        die("hooks.mailinglist is not set")
+
+    # Get the domain name to use in the From header
+    try:
+        maildomain = git.config("hooks.maildomain", _quiet=True)
+    except CalledProcessError:
+        pass
+
+    if not maildomain:
+        try:
+            hostname = gethostname()
+            maildomain = '.'.join(hostname.split('.')[1:])
+        except:
+            pass
+        if not maildomain or '.' not in maildomain:
+            maildomain = 'localhost.localdomain'
+
+    # Figure out a human-readable username
+    try:
+        entry = pwd.getpwuid(os.getuid())
+        gecos = entry.pw_gecos
+    except:
+        gecos = None
+
+    if gecos != None:
+        # Typical GNOME account have John Doe <john.doe@example.com> for the GECOS.
+        # Comma-separated fields are also possible
+        m = re.match("([^,<]+)", gecos)
+        if m:
+            fullname = m.group(1).strip()
+            if fullname != "":
+                try:
+                    user_fullname = unicode(fullname, 'ascii')
+                except UnicodeDecodeError:
+                    user_fullname = Header(fullname, 'utf-8').encode()
+
+    changes = []
+
+    if len(sys.argv) > 1:
+        # For testing purposes, allow passing in a ref update on the command line
+        if len(sys.argv) != 4:
+            die("Usage: generate-commit-mail OLDREV NEWREV REFNAME")
+        changes.append(make_change(sys.argv[1], sys.argv[2], sys.argv[3]))
+    else:
+        for line in sys.stdin:
+            items = line.strip().split()
+            if len(items) != 3:
+                die("Input line has unexpected number of items")
+            changes.append(make_change(items[0], items[1], items[2]))
+
+    for change in changes:
+        all_changes[change.refname] = change
+
+    for change in changes:
+        change.prepare()
+        change.send_emails()
+        processed_changes[change.refname] = change
+
+if __name__ == '__main__':
+    main()
diff --git a/roles/git/hooks/files/post-received-chained b/roles/git/hooks/files/post-received-chained
new file mode 100644
index 000000000..b5c6e2311
--- /dev/null
+++ b/roles/git/hooks/files/post-received-chained
@@ -0,0 +1,8 @@
+#!/bin/bash
+# Redirect stdin to each of the post-receive hooks in place.
+
+# You need to explicitly add your hook to the following list
+# for it to be invoked.
+pee \
+    $GIT_DIR/hooks/post-receive-chained.d/post-receive-email \
+    $GIT_DIR/hooks/post-receive-chained.d/post-receive-fedmsg
diff --git a/roles/git/hooks/files/post-received-fedmsg b/roles/git/hooks/files/post-received-fedmsg
new file mode 100644
index 000000000..7bc9a140d
--- /dev/null
+++ b/roles/git/hooks/files/post-received-fedmsg
@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+import getpass
+import git
+import os
+import sys
+
+import fedmsg
+import fedmsg.config
+
+# Read in all the rev information git-receive-pack hands us.
+lines = [line.split() for line in sys.stdin.readlines()]
+
+# Use $GIT_DIR to determine where this repo is.
+abspath = os.path.abspath(os.environ['GIT_DIR'])
+repo_name = '.'.join(abspath.split(os.path.sep)[-1].split('.')[:-1])
+
+username = getpass.getuser()
+
+repo = git.repo.Repo(abspath)
+def _build_commit(rev):
+    old, rev, branch = rev
+    branch = '/'.join(branch.split('/')[2:])
+    commit = repo.rev_parse(rev=rev)
+
+    # We just don't handle these
+    if isinstance(commit, git.TagObject):
+        return None
+
+    return dict(
+        name=commit.author.name,
+        email=commit.author.email,
+        username=username,
+        summary=commit.summary,
+        message=commit.message,
+        stats=dict(
+            files=commit.stats.files,
+            total=commit.stats.total,
+        ),
+        rev=rev,
+        path=abspath,
+        repo=repo_name,
+        branch=branch,
+        agent=os.getlogin(),
+    )
+
+commits = map(_build_commit, lines)
+
+print "Emitting a message to the fedmsg bus."
+config = fedmsg.config.load_config([], None)
+config['active'] = True
+config['endpoints']['relay_inbound'] = config['relay_inbound']
+fedmsg.init(name='relay_inbound', cert_prefix='scm', **config)
+
+for commit in commits:
+
+    if commit is None:
+        continue
+
+    fedmsg.publish(
+        # Expect this to change to just "receive" in the future.
+        topic="receive",
+        msg=dict(commit=commit),
+        modname="git",
+    )
diff --git a/roles/git/hooks/files/util.py b/roles/git/hooks/files/util.py
new file mode 100644
index 000000000..f35019634
--- /dev/null
+++ b/roles/git/hooks/files/util.py
@@ -0,0 +1,153 @@
+# General Utility Functions used in our Git scripts
+#
+# Copyright (C) 2008  Owen Taylor
+# Copyright (C) 2009  Red Hat, Inc
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, If not, see
+# http://www.gnu.org/licenses/.
+
+import os
+import sys
+from subprocess import Popen
+import tempfile
+import time
+
+def die(message):
+    print >>sys.stderr, message
+    sys.exit(1)
+
+# This cleans up our generation code by allowing us to use the same indentation
+# for the first line and subsequent line of a multi-line string
+def strip_string(str):
+    start = 0
+    end = len(str)
+    if len(str) > 0 and str[0] == '\n':
+        start += 1
+    if len(str) > 1 and str[end - 1] == '\n':
+        end -= 1
+
+    return str[start:end]
+
+# How long to wait between mails (in seconds); the idea of waiting
+# is to try to make the sequence of mails we send out in order
+# actually get delivered in order. The waiting is done in a forked
+# subprocess and doesn't stall completion of the main script.
+EMAIL_DELAY = 5
+
+# Some line that can never appear in any email we send out
+EMAIL_BOUNDARY="---@@@--- gnome-git-email ---@@@---\n"
+
+# Run in subprocess
+def _do_send_emails(email_in):
+    email_files = []
+    current_file = None
+    last_line = None
+
+    # Read emails from the input pipe and write each to a file
+    for line in email_in:
+        if current_file is None:
+            current_file, filename = tempfile.mkstemp(suffix=".mail", prefix="gnome-post-receive-email-")
+            email_files.append(filename)
+
+        if line == EMAIL_BOUNDARY:
+            # Strip the last line if blank; see comment when writing
+            # the email boundary for rationale
+            if last_line.strip() != "":
+                os.write(current_file, last_line)
+            last_line = None
+            os.close(current_file)
+            current_file = None
+        else:
+            if last_line is not None:
+                os.write(current_file, last_line)
+            last_line = line
+
+    if current_file is not None:
+        if last_line is not None:
+            os.write(current_file, last_line)
+        os.close(current_file)
+
+    # We're done interacting with the parent process, the rest happens
+    # asynchronously; send out the emails one by one and remove the
+    # temporary files
+    for i, filename in enumerate(email_files):
+        if i != 0:
+            time.sleep(EMAIL_DELAY)
+
+        f = open(filename, "r")
+        process = Popen(["/usr/sbin/sendmail", "-t"],
+                        stdout=None, stderr=None, stdin=f)
+        process.wait()
+        f.close()
+
+        os.remove(filename)
+
+email_file = None
+
+# Start a new outgoing email; returns a file object that the
+# email should be written to. Call end_email() when done
+def start_email():
+    global email_file
+    if email_file is None:
+        email_pipe = os.pipe()
+        pid = os.fork()
+        if pid == 0:
+            # The child
+
+            os.close(email_pipe[1])
+            email_in = os.fdopen(email_pipe[0])
+
+            # Redirect stdin/stdout/stderr to/from /dev/null
+            devnullin = os.open("/dev/null", os.O_RDONLY)
+            os.close(0)
+            os.dup2(devnullin, 0)
+
+            devnullout = os.open("/dev/null", os.O_WRONLY)
+            os.close(1)
+            os.dup2(devnullout, 1)
+            os.close(2)
+            os.dup2(devnullout, 2)
+            os.close(devnullout)
+
+            # Fork again to daemonize
+            if os.fork() > 0:
+                sys.exit(0)
+
+            try:
+                _do_send_emails(email_in)
+            except Exception:
+                import syslog
+                import traceback
+
+                syslog.openlog(os.path.basename(sys.argv[0]))
+                syslog.syslog(syslog.LOG_ERR, "Unexpected exception sending mail")
+                for line in traceback.format_exc().strip().split("\n"):
+                    syslog.syslog(syslog.LOG_ERR, line)
+
+            sys.exit(0)
+
+        email_file = os.fdopen(email_pipe[1], "w")
+    else:
+        # The email might not end with a newline, so add one. We'll
+        # strip the last line, if blank, when emails, so the net effect
+        # is to add a newline to messages without one
+        email_file.write("\n")
+        email_file.write(EMAIL_BOUNDARY)
+
+    return email_file
+
+# Finish an email started with start_email
+def end_email():
+    global email_file
+    email_file.flush()
diff --git a/roles/git/hooks/tasks/main.yml b/roles/git/hooks/tasks/main.yml
new file mode 100644
index 000000000..6cf6b9d0f
--- /dev/null
+++ b/roles/git/hooks/tasks/main.yml
@@ -0,0 +1,22 @@
+---
+# tasklist for setting up git mail hooks
+
+- name: install needed packages
+  yum: pkg={{item}} state=present
+  with_items:
+  - git
+  - moreutils
+
+# This requires the fedmsg/base role
+- name: install the git hooks
+  copy: src={{item}} dest=/usr/share/git-core mode=0755
+  with_items:
+  - post-receive-fedmsg
+  - post-receive-chained
+
+- name: install the git mail hooks
+  copy: src={{item}} dest=/usr/share/git-core/mail-hooks mode=0755
+  with_items:
+  - util.py
+  - git.py
+  - gnome-post-receive-email