first implementation of the mail rework

src/paperless_mail/mail.py

@@ -0,0 +1,149 @@
+import email
+from datetime import datetime, timedelta, date
+from email.parser import BytesParser
+
+from django.utils.text import slugify
+from imap_tools import MailBox, MailBoxUnencrypted, AND, MailMessageFlags
+
+from documents.models import Correspondent
+from paperless_mail.models import MailAccount, MailRule
+
+
+class BaseMailAction:
+
+    def get_criteria(self):
+        return {}
+
+    def post_consume(self, M, message_uids, parameter):
+        pass
+
+
+class DeleteMailAction(BaseMailAction):
+
+    def post_consume(self, M, message_uids, parameter):
+        M.delete(message_uids)
+
+
+class MarkReadMailAction(BaseMailAction):
+
+    def get_criteria(self):
+        return {'seen': False}
+
+    def post_consume(self, M, message_uids, parameter):
+        M.seen(message_uids, True)
+
+
+class MoveMailAction(BaseMailAction):
+
+    def post_consume(self, M, message_uids, parameter):
+        M.move(message_uids, parameter)
+
+
+class FlagMailAction(BaseMailAction):
+
+    def get_criteria(self):
+        return {'flagged': False}
+
+    def post_consume(self, M, message_uids, parameter):
+        M.flag(message_uids, [MailMessageFlags.FLAGGED], True)
+
+
+def get_rule_action(action):
+    if action == MailRule.ACTION_FLAG:
+        return FlagMailAction()
+    elif action == MailRule.ACTION_DELETE:
+        return DeleteMailAction()
+    elif action == MailRule.ACTION_MOVE:
+        return MoveMailAction()
+    elif action == MailRule.ACTION_MARK_READ:
+        return MarkReadMailAction()
+    else:
+        raise ValueError("Unknown action.")
+
+
+def handle_mail_account(account):
+
+    if account.imap_security == MailAccount.IMAP_SECURITY_NONE:
+        mailbox = MailBoxUnencrypted(account.imap_server, account.imap_port)
+    elif account.imap_security == MailAccount.IMAP_SECURITY_STARTTLS:
+        mailbox = MailBox(account.imap_server, account.imap_port, starttls=True)
+    elif account.imap_security == MailAccount.IMAP_SECURITY_SSL:
+        mailbox = MailBox(account.imap_server, account.imap_port)
+    else:
+        raise ValueError("Unknown IMAP security")
+
+    with mailbox.login(account.username, account.password) as M:
+
+        for rule in account.rules.all():
+
+            M.folder.set(rule.folder)
+
+            maximum_age = date.today() - timedelta(days=rule.maximum_age)
+            criterias = {
+                "date_gte": maximum_age
+            }
+            if rule.filter_from:
+                criterias["from_"] = rule.filter_from
+            if rule.filter_subject:
+                criterias["subject"] = rule.filter_subject
+            if rule.filter_body:
+                criterias["body"] = rule.filter_body
+
+            action = get_rule_action(rule.action)
+            criterias = {**criterias, **action.get_criteria()}
+
+            messages = M.fetch(criteria=AND(**criterias), mark_seen=False)
+
+            post_consume_messages = []
+
+            for message in messages:
+                result = handle_message(M, message, rule)
+                if result:
+                    post_consume_messages.append(message.uid)
+
+            action.post_consume(M, post_consume_messages, rule.action_parameter)
+
+
+def handle_message(M, message, rule):
+    if not message.attachments:
+        return False
+
+    if rule.assign_correspondent_from == MailRule.CORRESPONDENT_FROM_NOTHING:
+        correspondent = None
+    elif rule.assign_correspondent_from == MailRule.CORRESPONDENT_FROM_EMAIL:
+        corerspondent_name = message.from_
+        correspondent = Correspondent.objects.get_or_create(
+            name=corerspondent_name, defaults={
+                "slug": slugify(corerspondent_name)
+            })[0]
+    elif rule.assign_correspondent_from == MailRule.CORRESPONDENT_FROM_NAME:
+        corerspondent_name = message.from_values.name if message.from_values and message.from_values.name else message.from_
+        correspondent = Correspondent.objects.get_or_create(
+            name=corerspondent_name, defaults={
+                "slug": slugify(corerspondent_name)
+            })[0]
+    elif rule.assign_correspondent_from == MailRule.CORRESPONDENT_FROM_CUSTOM:
+        correspondent = rule.assign_correspondent
+    else:
+        raise ValueError("Unknwown correspondent selector")
+
+    tag = rule.assign_tag
+
+    doc_type = rule.assign_document_type
+
+    for att in message.attachments:
+
+        if rule.assign_title_from == MailRule.TITLE_FROM_SUBJECT:
+            title = message.subject
+        elif rule.assign_title_from == MailRule.TITLE_FROM_FILENAME:
+            title = att.filename
+        else:
+            raise ValueError("Unknown title selector.")
+
+        if att.content_type == 'application/pdf':
+            print("This is where I would consume the file with name {} and I would "
+                  "give it the title '{}', correspondent '{}', tag '{}', and doc type"
+                  "'{}'."
+                  .format(att.filename, title, correspondent, tag, doc_type))
+
+    return True