Create new mail util function to get body text(s)

diff --git a/src/mail_utils.py b/src/mail_utils.py
index c0e46e5..2bd69c2 100644 (file)
--- a/src/mail_utils.py
+++ b/src/mail_utils.py
@@ -662,13 +662,75 @@ def get_user_mail(user, mailbox='INBOX', **kwargs):
     if mailbox != 'INBOX':
         folder = os.path.join(folder, cyrus_escape(mailbox))
     for filename in os.listdir(folder):
-        if not re.match('\d+\.', filename):
+        if not re.match(r'\d+\.', filename):
             continue
         full_path = os.path.join(folder, filename)
         yield full_path, parse_mail_file(os.path.join(folder, filename),
                                          **kwargs)
 
 
+def get_message_text(filename, fallback_encoding='iso8859-1',
+                     include_all_text=False):
+    """
+    Extract message text as string from email message.
+
+    Intended as complementary addition to get_user_mail, e.g. ::
+
+        for filename, msg in get_user_mail(user):
+            # rough filtering based on headers
+            if msg['Subject'] != 'Expected Subject':
+                continue
+            # get message text for closer inspection
+            text = get_message_text(filename)
+            if 'Expected Text' not in text:
+                continue
+            ...
+
+    Finds the first part in message that is of type text/plain and decodes it
+    using encoding specified in mail or otherwise fallback encoding. If none
+    found takes first part of type "text/*", or otherwise just the first part.
+
+    If include_all_text is True, all text/* parts are included, with text/plain
+    being the first.
+
+    :param str filename: complete path of message file in filesystem
+    :param bool include_all_text: include all "text/*" parts in returned text
+    :returns: text(s) of message
+    :rtype: [str] if include_all_text else str
+    """
+    result = []
+    msg = parse_mail_file(filename, headers_only=False)
+    for part in msg.walk():
+        if part.get_content_type() != 'text/plain':
+            continue
+        encoding = part.get_content_charset(fallback_encoding)
+        result.append(part.get_payload(decode=True).decode(encoding))
+
+    if result and not include_all_text:
+        return result[0]
+
+    # no text/plain found. Try only "text/":
+    for part in msg.walk():
+        cont_type = part.get_content_type()
+        if cont_type.startswith('text/') and cont_type != 'text/plain':
+            encoding = part.get_content_charset(fallback_encoding)
+            result.append(part.get_payload(decode=True).decode(encoding))
+
+    if result:
+        if not include_all_text:
+            return result[0]
+        return result
+
+    # no "text/" found. Just take first part
+    while msg.is_multipart():
+        msg = msg.get_payload(0)
+
+    encoding = msg.get_content_charset(fallback_encoding)
+    if include_all_text:
+        return [msg.get_payload(decode=True).decode(encoding), ]
+    return msg.get_payload(decode=True).decode(encoding)
+
+
 def cyrus_escape(user_or_folder, keep_path=False, regex=False):
     """
     Converts names of users or mailbox folders to cyrus format.