Copying the email package back, despite its failings.

1 files changed, 73 insertions, 0 deletions

diff --git a/Lib/email/iterators.py b/Lib/email/iterators.py
new file mode 100644
index 0000000..e4476e3
--- /dev/null
+++ b/Lib/email/iterators.py
@@ -0,0 +1,73 @@
+# Copyright (C) 2001-2006 Python Software Foundation
+# Author: Barry Warsaw
+# Contact: email-sig@python.org
+
+"""Various types of useful iterators and generators."""
+
+__all__ = [
+    'body_line_iterator',
+    'typed_subpart_iterator',
+    'walk',
+    # Do not include _structure() since it's part of the debugging API.
+    ]
+
+import sys
+from io import StringIO
+
+
+
+# This function will become a method of the Message class
+def walk(self):
+    """Walk over the message tree, yielding each subpart.
+
+    The walk is performed in depth-first order.  This method is a
+    generator.
+    """
+    yield self
+    if self.is_multipart():
+        for subpart in self.get_payload():
+            for subsubpart in subpart.walk():
+                yield subsubpart
+
+
+
+# These two functions are imported into the Iterators.py interface module.
+def body_line_iterator(msg, decode=False):
+    """Iterate over the parts, returning string payloads line-by-line.
+
+    Optional decode (default False) is passed through to .get_payload().
+    """
+    for subpart in msg.walk():
+        payload = subpart.get_payload(decode=decode)
+        if isinstance(payload, basestring):
+            for line in StringIO(payload):
+                yield line
+
+
+def typed_subpart_iterator(msg, maintype='text', subtype=None):
+    """Iterate over the subparts with a given MIME type.
+
+    Use `maintype' as the main MIME type to match against; this defaults to
+    "text".  Optional `subtype' is the MIME subtype to match against; if
+    omitted, only the main type is matched.
+    """
+    for subpart in msg.walk():
+        if subpart.get_content_maintype() == maintype:
+            if subtype is None or subpart.get_content_subtype() == subtype:
+                yield subpart
+
+
+
+def _structure(msg, fp=None, level=0, include_default=False):
+    """A handy debugging aid"""
+    if fp is None:
+        fp = sys.stdout
+    tab = ' ' * (level * 4)
+    print(tab + msg.get_content_type(), end='', file=fp)
+    if include_default:
+        print(' [%s]' % msg.get_default_type(), file=fp)
+    else:
+        print(file=fp)
+    if msg.is_multipart():
+        for subpart in msg.get_payload():
+            _structure(subpart, fp, level+1, include_default)