initial commit

Signed-off-by: Keenan Tims <ktims@gotroot.ca>

parsers.py

@@ -0,0 +1,54 @@
+from decimal import Decimal
+from email.message import EmailMessage
+from model import Transaction
+import re
+from uuid import UUID
+from datetime import datetime
+from logging import debug
+from abc import ABC, abstractmethod
+
+
+class TransactionParser(ABC):
+    @abstractmethod
+    def match(self, msg: EmailMessage) -> bool:
+        pass
+
+    @abstractmethod
+    def extract(self, msg: EmailMessage) -> Transaction:
+        pass
+
+
+class TransactionParsingFailed(Exception):
+    pass
+
+
+class RogersBankParser(TransactionParser):
+    EXTRACT_RE = re.compile(
+        r"Attempt of \$(\d+\.\d{2}) was made on ([A-z]{3} \d{1,2}, \d{4})[^<]*at ([^<]+) in"
+    )
+
+    def __init__(self, account_id: UUID):
+        self.account_id = account_id
+
+    def match(self, msg: EmailMessage) -> bool:
+        return (
+            msg["From"] == "Rogers Bank <onlineservices@RogersBank.com>"
+            and msg["Subject"] == "Purchase amount alert"
+        )
+
+    def extract(self, msg: EmailMessage) -> Transaction:
+        matches = RogersBankParser.EXTRACT_RE.search(msg.get_body().as_string())
+        if matches is None:
+            return TransactionParsingFailed("No matches for extraction RE")
+        amount = Decimal(matches[1])
+        date_raw = matches[2]
+        payee = matches[3]
+        date = datetime.strptime(date_raw, "%b %d, %Y").date()
+        return Transaction(
+            account=self.account_id,
+            date=date,
+            amount=amount,
+            payee=payee,
+            notes="via email",
+            imported_id=msg["Message-ID"],
+        )