autorun support

disabled by default, and configurable via trailets

Author: jimdigriz

nbgitpuller/pull.py

@@ -1,10 +1,11 @@
 import os
+import re
 import subprocess
 import logging
 import time
 import argparse
 import datetime
-from traitlets import Integer, default
+from traitlets import Bool, CRegExp, Integer, List, Unicode, Union, default
 from traitlets.config import Configurable
 from functools import partial
 
@@ -49,6 +50,33 @@ def flush():
 
 
 class GitPuller(Configurable):
+    autorun_allow = Union(
+        [List(CRegExp()), Bool()],
+        default_value=False,
+        config=True,
+        help="""
+        List of URLs described as Python regular expressions (using re.fullmatch()) where
+        it is permitted to autorun scripts from the pulled project as a pre-initialisation
+        step. Enable this only if you understand and accept the risks of AUTORUN.INF.
+
+        When set to boolean True, all URLs are allowed, whilst False (default) autorun
+        is disabled completely.
+        """
+    )
+
+    autorun_script = List(
+        Unicode(),
+        default_value=[],
+        config=True,
+        help="""
+        List of scripts to search for when attempting to autorun. The first match will
+        be run with a single argument of 'init' or 'update' depending on what nbgitpuller
+        is doing.
+
+        Enable this only if you understand and accept the risks of AUTORUN.INF.
+        """
+    )
+
     depth = Integer(
         config=True,
         help="""
@@ -143,6 +171,25 @@ def pull(self):
         else:
             yield from self.update()
 
+    def autorun(self, operation="method"):
+        """
+        Search for and execute the autorun script.
+        """
+
+        if not self.autorun_allow:
+            return
+        if not any(( re.fullmatch(pattern, self.git_url) for pattern in self.autorun_allow )):
+            logging.info('autorun skipped, URL does not match any rules')
+            return
+
+        script = next(( s for s in self._autorun_script if os.path.exists(os.path.join(self.repo_dir, s)) ), None)
+        if not script:
+            logging.info('autorun skipped, no matching script')
+            return
+
+        logging.info('autorun executing: %s %s', script, operation)
+        yield from execute_cmd([ script, operation ], cwd=self.repo_dir, shell=True)
+
     def initialize_repo(self):
         """
         Clones repository
@@ -154,6 +201,7 @@ def initialize_repo(self):
         clone_args.extend(['--branch', self.branch_name])
         clone_args.extend(["--", self.git_url, self.repo_dir])
         yield from execute_cmd(clone_args)
+        self.autorun('init')
         logging.info('Repo {} initialized'.format(self.repo_dir))
 
     def reset_deleted_files(self):
@@ -343,6 +391,7 @@ def update(self):
         yield from self.ensure_lock()
         yield from self.merge()
 
+        self.autorun('update')
 
 def main():
     """