meta_receipt: Use check-id as fallback metadata for outgoing checks.

When we send checks, we don't have a check document anywhere (for
security reasons), we just note the check number. Update the
validation to match. RT#10507.

conservancy_beancount/plugin/meta_receipt.py

@@ -14,14 +14,23 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+from decimal import Decimal
+
 from . import core
 from .. import config as configmod
 from .. import data
 from .. import errors as errormod
 from ..beancount_types import (
+    MetaKey,
     Transaction,
 )
 
+from typing import (
+    Callable,
+)
+
+_CheckMethod = Callable[[Transaction, data.Posting, MetaKey], None]
+
 class MetaReceipt(core._RequireLinksPostingMetadataHook):
     METADATA_KEY = 'receipt'
 
@@ -35,6 +44,13 @@ class MetaReceipt(core._RequireLinksPostingMetadataHook):
             and abs(post.units.number) >= self.payment_threshold
         )
 
+    def _check_check_id(self, txn: Transaction, post: data.Posting, key: MetaKey) -> None:
+        value = post.meta.get(key)
+        if (not isinstance(value, Decimal)
+            or value < 1
+            or value % 1):
+            raise errormod.InvalidMetadataError(txn, key, value, post, Decimal)
+
     def post_run(self, txn: Transaction, post: data.Posting) -> errormod.Iter:
         try:
             self._check_links(txn, post, self.METADATA_KEY)
@@ -50,7 +66,12 @@ class MetaReceipt(core._RequireLinksPostingMetadataHook):
         else:
             post_amount = -1
 
+        check_method: _CheckMethod = self._check_links
         if post.account.is_checking():
+            if post_amount == -1:
+                check_method = self._check_check_id
+                fallback_key = 'check-id'
+            else:
                 fallback_key = 'check'
         elif post.account.is_credit_card() and post_amount == -1:
             fallback_key = 'invoice'
@@ -61,7 +82,7 @@ class MetaReceipt(core._RequireLinksPostingMetadataHook):
             return
 
         try:
-            self._check_links(txn, post, fallback_key)
+            check_method(txn, post, fallback_key)
         except errormod.InvalidMetadataError as fallback_error:
             if receipt_error.value is None and fallback_error.value is None:
                 yield errormod.InvalidMetadataError(

tests/test_meta_receipt.py

@@ -48,17 +48,21 @@ class AccountForTesting(typing.NamedTuple):
         return f"{self.name} missing {TEST_KEY}{rest}"
 
     def wrong_type_message(self, wrong_value, key=TEST_KEY):
-        return  "{} has wrong type of {}: expected str but is a {}".format(
+        expect_type = 'Decimal' if key == 'check-id' else 'str'
+        return  "{} has wrong type of {}: expected {} but is a {}".format(
             self.name,
             key,
+            expect_type,
             type(wrong_value).__name__,
         )
 
 
 ACCOUNTS = [AccountForTesting._make(t) for t in [
-    ('Assets:Bank:CheckCard', PostType.BOTH, 'check'),
+    ('Assets:Bank:CheckCard', PostType.CREDIT, 'check'),
+    ('Assets:Bank:CheckCard', PostType.DEBIT, 'check-id'),
     ('Assets:Cash', PostType.BOTH, None),
-    ('Assets:Checking', PostType.BOTH, 'check'),
+    ('Assets:Checking', PostType.CREDIT, 'check'),
+    ('Assets:Checking', PostType.DEBIT, 'check-id'),
     ('Assets:PayPal', PostType.CREDIT, 'paypal-id'),
     ('Assets:PayPal', PostType.DEBIT, None),
     ('Assets:Savings', PostType.BOTH, None),
@@ -66,9 +70,12 @@ ACCOUNTS = [AccountForTesting._make(t) for t in [
     ('Liabilities:CreditCard', PostType.DEBIT, 'invoice'),
 ]]
 
-ACCOUNTS_WITH_FALLBACKS = [acct for acct in ACCOUNTS if acct.fallback_meta]
+ACCOUNTS_WITH_LINK_FALLBACK = [acct for acct in ACCOUNTS
+                               if acct.fallback_meta and acct.fallback_meta != 'check-id']
+ACCOUNTS_WITH_CHECK_ID_FALLBACK = [acct for acct in ACCOUNTS
+                                   if acct.fallback_meta == 'check-id']
 ACCOUNTS_WITHOUT_FALLBACKS = [acct for acct in ACCOUNTS if not acct.fallback_meta]
-KNOWN_FALLBACKS = {acct.fallback_meta for acct in ACCOUNTS_WITH_FALLBACKS}
+KNOWN_FALLBACKS = {acct.fallback_meta for acct in ACCOUNTS if acct.fallback_meta}
 
 # These are mostly fill-in values.
 # We don't need to run every test on every value for these, just enough to
@@ -86,6 +93,14 @@ NOT_REQUIRED_ACCOUNTS = itertools.cycle([
     'Liabilities:UnearnedIncome:Donations',
 ])
 
+CHECK_IDS = (decimal.Decimal(n) for n in itertools.count(1))
+def BAD_CHECK_IDS():
+    # Valid check-id values are positive integers
+    yield decimal.Decimal(0)
+    yield -next(CHECK_IDS)
+    yield next(CHECK_IDS) * decimal.Decimal('1.1')
+BAD_CHECK_IDS = BAD_CHECK_IDS()
+
 def check(hook, test_acct, other_acct, expected, *,
           txn_meta={}, post_meta={}, check_type=PostType.BOTH, min_amt=0):
     check_type &= test_acct.required_types
@@ -167,7 +182,7 @@ def test_bad_type_receipt_on_txn(hook, test_acct, other_acct, value):
           txn_meta={TEST_KEY: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.LINK_METADATA_STRINGS,
 ))
@@ -176,7 +191,7 @@ def test_valid_fallback_on_post(hook, test_acct, other_acct, value):
           post_meta={test_acct.fallback_meta: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.NON_LINK_METADATA_STRINGS,
 ))
@@ -185,7 +200,7 @@ def test_invalid_fallback_on_post(hook, test_acct, other_acct, value):
           post_meta={test_acct.fallback_meta: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.NON_STRING_METADATA_VALUES,
 ))
@@ -198,7 +213,7 @@ def test_bad_type_fallback_on_post(hook, test_acct, other_acct, value):
           post_meta={test_acct.fallback_meta: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.LINK_METADATA_STRINGS,
 ))
@@ -207,7 +222,7 @@ def test_valid_fallback_on_txn(hook, test_acct, other_acct, value):
           txn_meta={test_acct.fallback_meta: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.NON_LINK_METADATA_STRINGS,
 ))
@@ -216,7 +231,7 @@ def test_invalid_fallback_on_txn(hook, test_acct, other_acct, value):
           txn_meta={test_acct.fallback_meta: value})
 
 @pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
-    ACCOUNTS_WITH_FALLBACKS,
+    ACCOUNTS_WITH_LINK_FALLBACK,
     NOT_REQUIRED_ACCOUNTS,
     testutil.NON_STRING_METADATA_VALUES,
 ))
@@ -228,6 +243,80 @@ def test_bad_type_fallback_on_txn(hook, test_acct, other_acct, value):
     check(hook, test_acct, other_acct, expected,
           txn_meta={test_acct.fallback_meta: value})
 
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    CHECK_IDS,
+))
+def test_valid_check_id_on_post(hook, test_acct, other_acct, value):
+    check(hook, test_acct, other_acct, None,
+          post_meta={test_acct.fallback_meta: value})
+
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    BAD_CHECK_IDS,
+))
+def test_invalid_check_id_on_post(hook, test_acct, other_acct, value):
+    expected = {
+        test_acct.missing_message(False),
+        f"{test_acct.name} has invalid {test_acct.fallback_meta}: {value}",
+    }
+    check(hook, test_acct, other_acct, expected,
+          post_meta={test_acct.fallback_meta: value})
+
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    testutil.NON_STRING_METADATA_VALUES,
+))
+def test_bad_type_check_id_on_post(hook, test_acct, other_acct, value):
+    if isinstance(value, decimal.Decimal):
+        value = ''
+    expected = {
+        test_acct.missing_message(False),
+        test_acct.wrong_type_message(value, test_acct.fallback_meta),
+    }
+    check(hook, test_acct, other_acct, expected,
+          post_meta={test_acct.fallback_meta: value})
+
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    CHECK_IDS,
+))
+def test_valid_check_id_on_txn(hook, test_acct, other_acct, value):
+    check(hook, test_acct, other_acct, None,
+          txn_meta={test_acct.fallback_meta: value})
+
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    BAD_CHECK_IDS,
+))
+def test_invalid_check_id_on_txn(hook, test_acct, other_acct, value):
+    expected = {
+        test_acct.missing_message(False),
+        f"{test_acct.name} has invalid {test_acct.fallback_meta}: {value}",
+    }
+    check(hook, test_acct, other_acct, expected,
+          txn_meta={test_acct.fallback_meta: value})
+
+@pytest.mark.parametrize('test_acct,other_acct,value', testutil.combine_values(
+    ACCOUNTS_WITH_CHECK_ID_FALLBACK,
+    NOT_REQUIRED_ACCOUNTS,
+    testutil.NON_STRING_METADATA_VALUES,
+))
+def test_bad_type_check_id_on_txn(hook, test_acct, other_acct, value):
+    if isinstance(value, decimal.Decimal):
+        value = ''
+    expected = {
+        test_acct.missing_message(False),
+        test_acct.wrong_type_message(value, test_acct.fallback_meta),
+    }
+    check(hook, test_acct, other_acct, expected,
+          txn_meta={test_acct.fallback_meta: value})
+
 @pytest.mark.parametrize('test_acct,other_acct,key,value', testutil.combine_values(
     ACCOUNTS_WITHOUT_FALLBACKS,
     NOT_REQUIRED_ACCOUNTS,