Load up all subfolders from Maildir and MH boxes.

Closes #123.

changelog.rst

@@ -7,6 +7,8 @@ ChangeLog
 
 .. note:: This version is not yet released and is under active development
 
+* Load up all subfolders from ``Maildir`` and ``MH`` boxes. Closes #123.
+
 
 `6.0.1 (2020-10-22) <https://github.com/kdeldycke/mail-deduplicate/compare/v6.0.0...v6.0.1>`_
 ---------------------------------------------------------------------------------------------

mail_deduplicate/deduplicate.py

@@ -329,15 +329,16 @@ def add_source(self, source_path):
         if source_path in self.sources:
             raise ValueError(f"{source_path} already added.")
 
-        # Open and register the mail source.
-        box = open_box(source_path, self.conf.input_format, self.conf.force_unlock)
-        assert source_path == box._path
-        self.sources[source_path] = box
-
-        # Track of global mail count.
-        mail_found = len(box)
-        logger.info(f"{mail_found} mails found.")
-        self.stats["mail_found"] += mail_found
+        # Open and register the mail source. Subfolders will be registered as their
+        # own box.
+        boxes = open_box(source_path, self.conf.input_format, self.conf.force_unlock)
+        for box in boxes:
+            self.sources[box._path] = box
+
+            # Track global mail count.
+            mail_found = len(box)
+            logger.info(f"{mail_found} mails found.")
+            self.stats["mail_found"] += mail_found
 
     def hash_all(self):
         """Browse all mails from all registered sources, compute hashes and group mails

mail_deduplicate/mailbox.py

@@ -129,10 +129,10 @@ def autodetect_box_type(path):
 def open_box(path, box_type=False, force_unlock=False):
     """Open a mailbox.
 
-    Returns the locked box, ready for operations.
+    Returns a list of boxes, one per sub-folder. All are locked, ready for operations.
 
-    If ``box_type`` is specified, forces the opening of the box in the
-    specified format. Else try to autodetect the type.
+    If ``box_type`` is provided, forces the opening of the box in the specified format.
+    Defaults to (crude) autodetection.
     """
     logger.info(f"Opening {choice_style(path)} ...")
     path = Path(path)
@@ -145,6 +145,14 @@ def open_box(path, box_type=False, force_unlock=False):
     # Do not allow the constructor to create a new mailbox if not found.
     box = constructor(path, create=False)
 
+    return open_subfolders(box, force_unlock)
+
+
+def lock_box(box, force_unlock):
+    """ Lock an opened box and allows for forced unlocking.
+
+    Returns the locked box.
+    """
     try:
         logger.debug("Locking box...")
         box.lock()
@@ -160,11 +168,25 @@ def open_box(path, box_type=False, force_unlock=False):
         # Re-raise error.
         else:
             raise
-
     logger.debug("Box opened.")
     return box
 
 
+def open_subfolders(box, force_unlock):
+    """ Browse recursively the subfolder tree of a box.
+
+    Returns a list of opened and locked boxes, each for one subfolder.
+    """
+    folder_list = [lock_box(box, force_unlock)]
+
+    # Skip box types not supporting subfolders.
+    if hasattr(box, "list_folders"):
+        for folder_id in box.list_folders():
+            logger.info(f"Opening subfolder {folder_id} ...")
+            folder_list += open_subfolders(box.get_folder(folder_id), force_unlock)
+    return folder_list
+
+
 def create_box(path, box_type=False):
     """Creates a brand new box from scratch."""
     assert isinstance(path, Path)