diff --git a/src/_zkapauthorizer/model.py b/src/_zkapauthorizer/model.py
index ab0a19a6fc4046970a1b09750d9ef361d0c44bf4..ba9089e9244280932f4c5e31b5608671fa7a99a8 100644
--- a/src/_zkapauthorizer/model.py
+++ b/src/_zkapauthorizer/model.py
@@ -325,6 +325,43 @@ class VoucherStore(object):
(len(unblinded_tokens), voucher),
)
+ @with_cursor
+ def mark_voucher_double_spent(self, cursor, voucher):
+ """
+ Mark a voucher as having failed redemption because it has already been
+ spent.
+ """
+ cursor.execute(
+ """
+ UPDATE [vouchers]
+ SET [state] = "double-spend"
+ WHERE [number] = ?
+ AND [state] = "pending"
+ """,
+ (voucher,)
+ )
+ if cursor.rowcount == 0:
+ # Was there no matching voucher or was it in the wrong state?
+ cursor.execute(
+ """
+ SELECT [state]
+ FROM [vouchers]
+ WHERE [number] = ?
+ """,
+ (voucher,)
+ )
+ rows = cursor.fetchall()
+ if len(rows) == 0:
+ raise ValueError("Voucher {} not found".format(voucher))
+ else:
+ raise ValueError(
+ "Voucher {} in state {} cannot transition to double-spend".format(
+ voucher,
+ rows[0][0],
+ ),
+ )
+
+
@with_cursor
def extract_unblinded_tokens(self, cursor, count):
"""
diff --git a/src/_zkapauthorizer/tests/test_model.py b/src/_zkapauthorizer/tests/test_model.py
index 615d202bc0f76bba753dfb3d6e9d7d5b7b9f38b2..2abed45fe8b4fbee625a261d45bba8210a2dea82 100644
--- a/src/_zkapauthorizer/tests/test_model.py
+++ b/src/_zkapauthorizer/tests/test_model.py
@@ -104,13 +104,7 @@ class VoucherStoreTests(TestCase):
``VoucherStore.get`` raises ``KeyError`` when called with a
voucher not previously added to the store.
"""
- tempdir = self.useFixture(TempDir())
- config = get_config(tempdir.join(b"node"), b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
+ store = store_for_test(self, get_config, lambda: now)
self.assertThat(
lambda: store.get(voucher),
raises(KeyError),
@@ -122,13 +116,7 @@ class VoucherStoreTests(TestCase):
``VoucherStore.get`` returns a ``Voucher`` representing a voucher
previously added to the store with ``VoucherStore.add``.
"""
- tempdir = self.useFixture(TempDir())
- config = get_config(tempdir.join(b"node"), b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
+ store = store_for_test(self, get_config, lambda: now)
store.add(voucher, tokens)
self.assertThat(
store.get(voucher),
@@ -145,13 +133,7 @@ class VoucherStoreTests(TestCase):
More than one call to ``VoucherStore.add`` with the same argument results
in the same state as a single call.
"""
- tempdir = self.useFixture(TempDir())
- config = get_config(tempdir.join(b"node"), b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
+ store = store_for_test(self, get_config, lambda: now)
store.add(voucher, tokens)
store.add(voucher, [])
self.assertThat(
@@ -171,15 +153,7 @@ class VoucherStoreTests(TestCase):
``VoucherStore.list`` returns a ``list`` containing a ``Voucher`` object
for each voucher previously added.
"""
- tempdir = self.useFixture(TempDir())
- nodedir = tempdir.join(b"node")
- config = get_config(nodedir, b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
-
+ store = store_for_test(self, get_config, lambda: now)
for voucher in vouchers:
store.add(voucher, [])
@@ -238,6 +212,7 @@ class VoucherStoreTests(TestCase):
If the underlying database file cannot be opened then
``VoucherStore.from_node_config`` raises ``StoreOpenError``.
"""
+
tempdir = self.useFixture(TempDir())
nodedir = tempdir.join(b"node")
@@ -282,13 +257,7 @@ class UnblindedTokenStoreTests(TestCase):
"""
Unblinded tokens that are added to the store can later be retrieved.
"""
- tempdir = self.useFixture(TempDir())
- config = get_config(tempdir.join(b"node"), b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
+ store = store_for_test(self, get_config, lambda: now)
store.insert_unblinded_tokens_for_voucher(voucher_value, tokens)
retrieved_tokens = store.extract_unblinded_tokens(len(tokens))
self.expectThat(tokens, AfterPreprocessing(sorted, Equals(retrieved_tokens)))
@@ -326,13 +295,7 @@ class UnblindedTokenStoreTests(TestCase):
),
)
- tempdir = self.useFixture(TempDir())
- config = get_config(tempdir.join(b"node"), b"tub.port")
- store = VoucherStore.from_node_config(
- config,
- lambda: now,
- memory_connect,
- )
+ store = store_for_test(self, get_config, lambda: now)
store.add(voucher_value, random)
store.insert_unblinded_tokens_for_voucher(voucher_value, unblinded)
loaded_voucher = store.get(voucher_value)
@@ -343,3 +306,105 @@ class UnblindedTokenStoreTests(TestCase):
token_count=Equals(num_tokens),
),
)
+
+ @given(
+ tahoe_configs(),
+ datetimes(),
+ vouchers(),
+ lists(random_tokens(), unique=True),
+ )
+ def test_mark_vouchers_double_spent(self, get_config, now, voucher_value, random_tokens):
+ """
+ A voucher which is reported as double-spent is marked in the database as
+ such.
+ """
+ store = store_for_test(self, get_config, lambda: now)
+ store.add(voucher_value, random_tokens)
+ store.mark_voucher_double_spent(voucher_value)
+ voucher = store.get(voucher_value)
+ self.assertThat(
+ voucher,
+ MatchesStructure(
+ state=Equals(u"double-spend"),
+ ),
+ )
+
+ @given(
+ tahoe_configs(),
+ datetimes(),
+ vouchers(),
+ integers(min_value=1, max_value=100),
+ data(),
+ )
+ def test_mark_spent_vouchers_double_spent(self, get_config, now, voucher_value, num_tokens, data):
+ """
+ A voucher which has already been spent cannot be marked as double-spent.
+ """
+ random = data.draw(
+ lists(
+ random_tokens(),
+ min_size=num_tokens,
+ max_size=num_tokens,
+ unique=True,
+ ),
+ )
+ unblinded = data.draw(
+ lists(
+ unblinded_tokens(),
+ min_size=num_tokens,
+ max_size=num_tokens,
+ unique=True,
+ ),
+ )
+ store = store_for_test(self, get_config, lambda: now)
+ store.add(voucher_value, random)
+ store.insert_unblinded_tokens_for_voucher(voucher_value, unblinded)
+ try:
+ result = store.mark_voucher_double_spent(voucher_value)
+ except ValueError:
+ pass
+ except Exception as e:
+ self.fail("mark_voucher_double_spent raised the wrong exception: {}".format(e))
+ else:
+ self.fail("mark_voucher_double_spent didn't raise, returned: {}".format(result))
+
+ @given(
+ tahoe_configs(),
+ datetimes(),
+ vouchers(),
+ )
+ def test_mark_invalid_vouchers_double_spent(self, get_config, now, voucher_value):
+ """
+ A voucher which is not known cannot be marked as double-spent.
+ """
+ store = store_for_test(self, get_config, lambda: now)
+ try:
+ result = store.mark_voucher_double_spent(voucher_value)
+ except ValueError:
+ pass
+ except Exception as e:
+ self.fail("mark_voucher_double_spent raised the wrong exception: {}".format(e))
+ else:
+ self.fail("mark_voucher_double_spent didn't raise, returned: {}".format(result))
+
+
+def store_for_test(testcase, get_config, get_now):
+ """
+ Create a ``VoucherStore`` in a temporary directory associated with the
+ given test case.
+
+ :param TestCase testcase: The test case for which to build the store.
+ :param get_config: A function like the one built by ``tahoe_configs``.
+ :param get_now: A no-argument callable that returns a datetime giving a
+ time to consider as "now".
+
+ :return VoucherStore: A newly created temporary store.
+ """
+ tempdir = testcase.useFixture(TempDir())
+ config = get_config(tempdir.join(b"node"), b"tub.port")
+ store = VoucherStore.from_node_config(
+ config,
+ get_now,
+ memory_connect,
+ )
+ return store