add merge-directories

merge-directories.py

@@ -0,0 +1,72 @@
+#!/usr/bin/env python
+
+
+import sys
+import os
+import re
+import argparse
+import logging
+import contextlib
+
+
+class Tool(object):
+
+    def __init__(self, args):
+        self.args = args
+        self.dry_run_cache = set()
+
+    def run(self):
+        for directory in self.args.source_directory:
+            self.merge_directory(directory)
+
+    def merge_directory(self, source_directory_root):
+        source_directory_root = os.path.abspath(os.path.expanduser(source_directory_root))
+        print 'Merging {} into {}'.format(source_directory_root, self.args.destination)
+        for dirpath, dirnames, filenames in os.walk(source_directory_root):
+            for filename in filenames:
+                source_path = os.path.join(dirpath, filename)
+                source_rel_path = os.path.relpath(source_path, start=source_directory_root)
+                destination_path = os.path.join(self.args.destination, source_rel_path)
+                destination_dir_path = os.path.dirname(destination_path)
+
+                while os.path.exists(destination_path):
+                    head, tail = os.path.splitext(destination_path)
+                    number = 2
+                    match = re.match(r'(.+)_(\d+)$', head)
+                    if match:
+                        number = int(match.group(2)) + 1
+                        head = match.group(1)
+                    new_destination_path = head + '_' + str(number) + tail
+                    print '{} exists: {}'.format(destination_path, new_destination_path)
+                    destination_path = new_destination_path
+
+                if not os.path.exists(destination_dir_path):
+                    if not self.is_dry_run('Create directory {}'.format(destination_dir_path), unique=True):
+                        os.makedirs(destination_dir_path)
+
+                if not self.is_dry_run('Link {} -> {}'.format(source_path, destination_path)):
+                    os.link(source_path, destination_path)            
+
+    def is_dry_run(self, description, unique=False):
+        if self.args.dry_run:
+            should_print = True
+            if unique:
+                if description in self.dry_run_cache:
+                    should_print = False
+                else:
+                    self.dry_run_cache.add(description)
+            if should_print:
+                print 'Dry run: {}'.format(description)
+        return self.args.dry_run
+
+    @classmethod
+    def main(cls):
+        parser = argparse.ArgumentParser(description='Merge/Overlay directories')
+        parser.add_argument('-d', '--destination', required=True, help='Destination directory')
+        parser.add_argument('source_directory', nargs='+', help='Path to source directory to merge into destination directory')
+        parser.add_argument('-n', '--dry-run', action='store_true', help='Dry run')
+        args = parser.parse_args()
+        cls(args).run()
+
+if __name__ == "__main__":
+    Tool.main()