1 files changed, 134 insertions, 0 deletions
diff --git a/install-files.configure b/install-files.configure
new file mode 100755
index 00000000..341cce61
--- /dev/null
+++ b/install-files.configure
@@ -0,0 +1,134 @@
+#!/usr/bin/python
+# Copyright (C) 2013-2015  Codethink Limited
+#
+# 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; version 2 of the License.
+#
+# 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, see <http://www.gnu.org/licenses/>.
+
+
+''' A Morph configuration extension for adding arbitrary files to a system
+
+It will read the manifest files specified in the environment variable
+INSTALL_FILES, then use the contens of those files to determine which files
+to install into the target system.
+
+'''
+
+import cliapp
+import os
+import errno
+import re
+import sys
+import shlex
+import shutil
+import stat
+
+try:
+    import jinja2
+    jinja_available = True
+except ImportError:
+    jinja_available = False
+
+class InstallFilesConfigureExtension(cliapp.Application):
+
+    def process_args(self, args):
+        if not 'INSTALL_FILES' in os.environ:
+            return
+        target_root = args[0]
+        manifests = shlex.split(os.environ['INSTALL_FILES'])
+        for manifest in manifests:
+            self.install_manifest(manifest, target_root)
+
+    def install_manifest(self, manifest, target_root):
+        manifest_dir = os.path.dirname(manifest)
+        with open(manifest) as f:
+            entries = f.readlines()
+            for entry in entries:
+                self.install_entry(entry, manifest_dir, target_root)
+
+    def force_symlink(self, source, link_name):
+        try:
+            os.symlink(source, link_name)
+        except OSError as e:
+            if e.errno == errno.EEXIST:
+                os.remove(link_name)
+                os.symlink(source, link_name)
+
+    def install_entry(self, entry, manifest_root, target_root):
+        m = re.match('(template )?(overwrite )?'
+                     '([0-7]+) ([0-9]+) ([0-9]+) (\S+)', entry)
+
+        if m:
+            template = m.group(1)
+            overwrite = m.group(2)
+            mode = int(m.group(3), 8)   # mode is octal
+            uid = int(m.group(4))
+            gid = int(m.group(5))
+            path = m.group(6)
+        else:
+            raise cliapp.AppException('Invalid manifest entry, '
+                'format: [template] [overwrite] '
+                '<octal mode> <uid decimal> <gid decimal> <filename>')
+
+        dest_path = os.path.join(target_root, './' + path)
+        if stat.S_ISDIR(mode):
+            if os.path.exists(dest_path) and not overwrite:
+                dest_stat = os.stat(dest_path)
+                if (mode != dest_stat.st_mode
+                    or uid != dest_stat.st_uid
+                    or gid != dest_stat.st_gid):
+                        raise cliapp.AppException('"%s" exists and is not '
+                                                  'identical to directory '
+                                                  '"%s"' % (dest_path, entry))
+            else:
+                os.mkdir(dest_path, mode)
+                os.chown(dest_path, uid, gid)
+                os.chmod(dest_path, mode)
+
+        elif stat.S_ISLNK(mode):
+            if os.path.lexists(dest_path) and not overwrite:
+                raise cliapp.AppException('Symlink already exists at %s'
+                                          % dest_path)
+            else:
+                linkdest = os.readlink(os.path.join(manifest_root,
+                                                    './' + path))
+                self.force_symlink(linkdest, dest_path)
+                os.lchown(dest_path, uid, gid)
+
+        elif stat.S_ISREG(mode):
+            if os.path.lexists(dest_path) and not overwrite:
+                raise cliapp.AppException('File already exists at %s'
+                                           % dest_path)
+            else:
+                if template:
+                    if not jinja_available:
+                        raise cliapp.AppException(
+                            "Failed to install template file `%s': "
+                            'install-files templates require jinja2'
+                            % path)
+
+                    loader = jinja2.FileSystemLoader(manifest_root)
+                    env = jinja2.Environment(loader=loader,
+                                             keep_trailing_newline=True)
+
+                    env.get_template(path).stream(os.environ).dump(dest_path)
+                else:
+                    shutil.copyfile(os.path.join(manifest_root, './' + path),
+                                    dest_path)
+
+                os.chown(dest_path, uid, gid)
+                os.chmod(dest_path, mode)
+
+        else:
+            raise cliapp.AppException('Mode given in "%s" is not a file,'
+                                      ' symlink or directory' % entry)
+
+InstallFilesConfigureExtension().run()