diff --git a/src/_zkapauthorizer/model.py b/src/_zkapauthorizer/model.py
index 65d653ddf94ceaa3435fbaf9a2bb690029f4de4b..8a3b8ec91de583a8cf9195034ef7c75f1a71b5f3 100644
--- a/src/_zkapauthorizer/model.py
+++ b/src/_zkapauthorizer/model.py
@@ -41,6 +41,10 @@ from twisted.python.filepath import (
FilePath,
)
+from .storage_common import (
+ BYTES_PER_PASS,
+ required_passes,
+)
class StoreOpenError(Exception):
"""
@@ -157,6 +161,26 @@ def open_and_initialize(path, required_schema_version, connect=None):
)
""",
)
+ cursor.execute(
+ """
+ CREATE TABLE IF NOT EXISTS [lease-maintenance-spending] (
+ [id] integer, -- A unique identifier for a group of activity.
+ [started] text, -- ISO8601 date+time string when the activity began.
+ [finished] text, -- ISO8601 date+time string when the activity completed (or null).
+
+ -- The number of passes that would be required to renew all
+ -- shares encountered during this activity. Note that because
+ -- leases on different shares don't necessarily expire at the
+ -- same time this is not necessarily the number of passes
+ -- **actually** used during this activity. Some shares may
+ -- not have required lease renewal. Also note that while the
+ -- activity is ongoing this value may change.
+ [count] integer,
+
+ PRIMARY KEY([id])
+ )
+ """,
+ )
return conn
@@ -427,6 +451,140 @@ class VoucherStore(object):
u"unblinded-tokens": list(token for (token,) in tokens),
}
+ def start_lease_maintenance(self):
+ """
+ Get an object which can track a newly started round of lease maintenance
+ activity.
+
+ :return LeaseMaintenance: A new, started lease maintenance object.
+ """
+ m = LeaseMaintenance(self.now, self._connection)
+ m.start()
+ return m
+
+ @with_cursor
+ def get_latest_lease_maintenance_activity(self, cursor):
+ """
+ Get a description of the most recently completed lease maintenance
+ activity.
+
+ :return LeaseMaintenanceActivity|None: If any lease maintenance has
+ completed, an object describing its results. Otherwise, None.
+ """
+ cursor.execute(
+ """
+ SELECT [started], [count], [finished]
+ FROM [lease-maintenance-spending]
+ WHERE [finished] IS NOT NULL
+ ORDER BY [finished] DESC
+ LIMIT 1
+ """,
+ )
+ activity = cursor.fetchall()
+ if len(activity) == 0:
+ return None
+ [(started, count, finished)] = activity
+ return LeaseMaintenanceActivity(
+ parse_datetime(started, delimiter=u" "),
+ count,
+ parse_datetime(finished, delimiter=u" "),
+ )
+
+
+@attr.s
+class LeaseMaintenance(object):
+ """
+ A state-updating helper for recording pass usage during a lease
+ maintenance run.
+
+ Get one of these from ``VoucherStore.start_lease_maintenance``. Then use
+ the ``observe`` and ``finish`` methods to persist state about a lease
+ maintenance run.
+
+ :ivar _now: A no-argument callable which returns a datetime giving a time
+ to use as current.
+
+ :ivar _connection: A SQLite3 connection object to use to persist observed
+ information.
+
+ :ivar _rowid: None for unstarted lease maintenance objects. For started
+ objects, the database row id that corresponds to the started run.
+ This is used to make sure future updates go to the right row.
+ """
+ _now = attr.ib()
+ _connection = attr.ib()
+ _rowid = attr.ib(default=None)
+
+ @with_cursor
+ def start(self, cursor):
+ """
+ Record the start of a lease maintenance run.
+ """
+ if self._rowid is not None:
+ raise Exception("Cannot re-start a particular _LeaseMaintenance.")
+
+ cursor.execute(
+ """
+ INSERT INTO [lease-maintenance-spending] ([started], [finished], [count])
+ VALUES (?, ?, ?)
+ """,
+ (self._now(), None, 0),
+ )
+ self._rowid = cursor.lastrowid
+
+ @with_cursor
+ def observe(self, cursor, size):
+ """
+ Record a storage object of a given size.
+ """
+ # XXX The client has no idea how many shares a server is storing and
+ # can do nothing except renew the lease on all of them. :( Here, guess
+ # that there is only one share. "Servers of happiness" should make
+ # this more likely to be the case... We might be underestimating
+ # storage costs though.
+ count = required_passes(BYTES_PER_PASS, {size})
+ cursor.execute(
+ """
+ UPDATE [lease-maintenance-spending]
+ SET [count] = [count] + ?
+ WHERE [id] = ?
+ """,
+ (count, self._rowid),
+ )
+
+ @with_cursor
+ def finish(self, cursor):
+ """
+ Record the completion of this lease maintenance run.
+ """
+ cursor.execute(
+ """
+ UPDATE [lease-maintenance-spending]
+ SET [finished] = ?
+ WHERE [id] = ?
+ """,
+ (self._now(), self._rowid),
+ )
+ self._rowid = None
+
+
+@attr.s
+class LeaseMaintenanceActivity(object):
+ started = attr.ib()
+ passes_required = attr.ib()
+ finished = attr.ib()
+
+
+# store = ...
+# x = store.start_lease_maintenance()
+# x.observe(size=123)
+# x.observe(size=456)
+# ...
+# x.finish()
+#
+# x = store.get_latest_lease_maintenance_activity()
+# xs.started, xs.passes_required, xs.finished
+
@attr.s(frozen=True)
class UnblindedToken(object):
diff --git a/src/_zkapauthorizer/tests/test_model.py b/src/_zkapauthorizer/tests/test_model.py
index d31e669a9f2fd108fa67e25aa655ef747707e246..018eb07f20fc7e526b7d8b30305566c93ec0e29c 100644
--- a/src/_zkapauthorizer/tests/test_model.py
+++ b/src/_zkapauthorizer/tests/test_model.py
@@ -27,6 +27,9 @@ from os import (
from errno import (
EACCES,
)
+from datetime import (
+ timedelta,
+)
from testtools import (
TestCase,
@@ -52,7 +55,9 @@ from hypothesis import (
from hypothesis.strategies import (
data,
lists,
+ tuples,
datetimes,
+ timedeltas,
integers,
)
@@ -60,6 +65,10 @@ from twisted.python.filepath import (
FilePath,
)
+from ..storage_common import (
+ BYTES_PER_PASS,
+)
+
from ..model import (
SchemaError,
StoreOpenError,
@@ -68,6 +77,7 @@ from ..model import (
Pending,
DoubleSpend,
Redeemed,
+ LeaseMaintenanceActivity,
open_and_initialize,
memory_connect,
)
@@ -78,6 +88,7 @@ from .strategies import (
voucher_objects,
random_tokens,
unblinded_tokens,
+ posix_safe_datetimes,
)
from .fixtures import (
TemporaryVoucherStore,
@@ -217,7 +228,6 @@ 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")
@@ -238,6 +248,73 @@ class VoucherStoreTests(TestCase):
)
+class LeaseMaintenanceTests(TestCase):
+ """
+ Tests for the lease-maintenance related parts of ``VoucherStore``.
+ """
+ @given(
+ tahoe_configs(),
+ posix_safe_datetimes(),
+ lists(
+ tuples(
+ # How much time passes before this activity starts
+ timedeltas(min_value=timedelta(0), max_value=timedelta(days=1)),
+ # Some activity. This list of two tuples gives us a trivial
+ # way to compute the total passes required (just sum the pass
+ # counts in it). This is nice because it avoids having the
+ # test re-implement size quantization which would just be
+ # repeated code duplicating the implementation. The second
+ # value lets us fuzz the actual size values a little bit in a
+ # way which shouldn't affect the passes required.
+ lists(
+ tuples(
+ # The activity itself, in pass count
+ integers(min_value=1, max_value=2 ** 16 - 1),
+ # Amount by which to trim back the share sizes
+ integers(min_value=0, max_value=BYTES_PER_PASS - 1),
+ ),
+ ),
+ # How much time passes before this activity finishes
+ timedeltas(min_value=timedelta(0), max_value=timedelta(days=1)),
+ ),
+ ),
+ )
+ def test_lease_maintenance_activity(self, get_config, now, activity):
+ """
+ ``VoucherStore.get_latest_lease_maintenance_activity`` returns a
+ ``LeaseMaintenanceTests`` with fields reflecting the most recently
+ finished lease maintenance activity.
+ """
+ store = self.useFixture(
+ TemporaryVoucherStore(get_config, lambda: now),
+ ).store
+
+ expected = None
+ for (start_delay, sizes, finish_delay) in activity:
+ now += start_delay
+ started = now
+ x = store.start_lease_maintenance()
+ passes_required = 0
+ for (num_passes, trim_size) in sizes:
+ passes_required += num_passes
+ x.observe(num_passes * BYTES_PER_PASS - trim_size)
+ now += finish_delay
+ x.finish()
+ finished = now
+
+ # Let the last iteration of the loop define the expected value.
+ expected = LeaseMaintenanceActivity(
+ started,
+ passes_required,
+ finished,
+ )
+
+ self.assertThat(
+ store.get_latest_lease_maintenance_activity(),
+ Equals(expected),
+ )
+
+
class VoucherTests(TestCase):
"""
Tests for ``Voucher``.