Introduce changelog

        self.payload_path = os.path.join(path, "payload")

        self.validate_source_files()

        self.description = self.parse_description()

        self.changelog = self.parse_changelog()

        # script tarball path

        self.image_name = "%s-%s%s" % (self.description["name"],

                                       self.description["version"],

        # creating scripts tarball

        self.create_image(jdesc)

    def create_image(self, description):

    def create_image(self, jdescription):

        '''

        Create a script tarball in current directory

        '''

            raise Exception("Unable to create tarball %s: %s" % (self.image_name, e))

        # add .description.json

        arrow("Add description.json")

        tarball.add_str("description.json", description, tarfile.REGTYPE, 0444)

        tarball.add_str("description.json", jdescription, tarfile.REGTYPE, 0444)

        # add changelog

        changelog_path = os.path.join(self.base_path, "changelog")

        if os.path.exists(changelog_path):

        if self.changelog is not None:

            arrow("Add changelog")

            ti = tarball.gettarinfo(changelog_path, "changelog")

            ti.uid = ti.gid = 0

            ti.mode = 0644

            ti.uname = ti.gname = "root"

            tarball.addfile(ti, open(changelog_path, "rb"))

            tarball.add_str("changelog", self.changelog.verbatim, tarfile.REGTYPE, 0444)

        # add .format

        arrow("Add format")

        tarball.add_str("format", self.format, tarfile.REGTYPE, 0444)

            raise Exception("Bad description: %s" % e)

        return d

    def parse_changelog(self):

        '''

        Create a changelog object from a file

        '''

        # try to find a changelog file

        try:

            path = os.path.join(self.base_path, "changelog")

            fo = open(path, "r")

        except IOError:

            return None

        # we have it, we need to check everything is ok

        arrow("Parsing changelog")

        try:

            cl = Changelog(fo.read())

        except Exception as e:

            raise Exception("Bad changelog: %s" % e)

        return cl

class PackageImage(Image):

    '''

        '''

        Parse tarball and return metadata dict

        '''

        # extract metadata

        img_format = self._tarball.get_str("format")

        img_desc = self._tarball.get_str("description.json")

        desc = {}

        # check format

        img_format = self._tarball.get_str("format")

        if img_format != self.format:

            raise Exception("Invalid tarball image format")

        desc["format"] = img_format

        # check description

        try:

            desc = json.loads(img_desc)

            img_desc = self._tarball.get_str("description.json")

            desc.update(json.loads(img_desc))

            self.check_image_name(desc["name"])

            self.check_image_version(desc["version"])

        except Exception as e:

            raise Exception("Invalid description: %s" % e)

        # try to load changelog

        try:

            img_changelog = self._tarball.get_str("changelog")

            desc["changelog"] = Changelog(img_changelog)

        except KeyError:

            pass

        except Exception as e:

            warn("Invalid changelog: %s" % e)

        return desc

    def show(self, verbose=False):

                out('  #yellow#Date:#reset# %s' % time.ctime(payload.mtime))

                out('  #yellow#Size:#reset# %s' % (istools.human_size(payload.size)))

                out('  #yellow#MD5:#reset# %s' % payload.md5)

        # display image content

        out('#light##yellow#Content:#reset#')

        self._tarball.list(verbose)

        # display changelog

        try:

            self.changelog.show(int(self.version), verbose)

        except AttributeError:

            pass

    def check(self, message="Check MD5"):

        '''

        istools.chrights(dest, self.uid, self.gid, self.mode, self.mtime)

class Changelog(object):

class Changelog(dict):

    '''

    Object representing a changelog in memory

    '''

    def __init__(self):

        pass

    def __init__(self, data):

        self.verbatim = ""

        self.load(data)

    def load(self, data):

        '''

        Load a changelog file

        '''

        version = None

        lines = data.split("\n")

        for line in lines:

            # ignore empty lines

            if len(line.strip()) == 0:

                continue

            # ignore comments

            if line.lstrip().startswith("#"):

                continue

            # try to match a new version

            m = re.match("\[(\d+)\]", line.lstrip())

            if m is not None:

                version = int(m.group(1))

                self[version] = []

                continue

            # if line are out of a version => invalid format

            if version is None:

                raise Exception("Invalid format: Line outside version")

            # add line to version changelog

            self[version] += [line]

        # save original

        self.verbatim = data

    def show(self, version=None, verbose=False):

        '''

        Show changelog for a given version or all

        '''

        # if no version take the hightest

        if version is None:

            version = max(self)

        # in non verbose mode display only asked version if exists

        if not verbose and version not in self:

            print "chich"

            return

        out('#light##yellow#Changelog:#reset#')

        # display asked version

        out('  #yellow#Version:#reset# %s' % version)

        for line in self[version]:

            out("    %s" % line)

        # display all version in verbose mode

        if verbose:

            for ver in sorted((k for k in self if k < version), reverse=True):

                out('  #yellow#Version:#reset# %s' % ver)

                os.linesep.join(self[ver])

author =

"""

changelog = """==== 1 ====

changelog = """[1]

- Initial version

"""