diff --git a/src/_zkapauthorizer/model.py b/src/_zkapauthorizer/model.py
index 090411660a2873cb98769b2b68f10f86c2935718..d0066139e34ece2e4a1dd3b143c0b9b04d6b718b 100644
--- a/src/_zkapauthorizer/model.py
+++ b/src/_zkapauthorizer/model.py
@@ -61,6 +61,12 @@ from .storage_common import (
required_passes,
)
+from .schema import (
+ get_schema_version,
+ get_schema_upgrades,
+ run_schema_upgrades,
+)
+
class ILeaseMaintenanceObserver(Interface):
"""
@@ -88,13 +94,9 @@ class StoreOpenError(Exception):
self.reason = reason
-class SchemaError(TypeError):
- pass
-
-
CONFIG_DB_NAME = u"privatestorageio-zkapauthz-v1.sqlite3"
-def open_and_initialize(path, required_schema_version, connect=None):
+def open_and_initialize(path, connect=None):
"""
Open a SQLite3 database for use as a voucher store.
@@ -103,13 +105,6 @@ def open_and_initialize(path, required_schema_version, connect=None):
:param FilePath path: The location of the SQLite3 database file.
- :param int required_schema_version: The schema version which must be
- present in the database in order for a SQLite3 connection to be
- returned.
-
- :raise SchemaError: If the schema in the database does not match the
- required schema version.
-
:return: A SQLite3 connection object for the database at the given path.
"""
if connect is None:
@@ -135,86 +130,9 @@ def open_and_initialize(path, required_schema_version, connect=None):
with conn:
cursor = conn.cursor()
- cursor.execute(
- # This code knows how to create schema version 1. This is
- # regardless of what the caller *wants* to find in the database.
- """
- CREATE TABLE IF NOT EXISTS [version] AS SELECT 1 AS [version]
- """
- )
- cursor.execute(
- """
- SELECT [version] FROM [version]
- """
- )
- [(actual_version,)] = cursor.fetchall()
- if actual_version != required_schema_version:
- raise SchemaError(
- "Unexpected database schema version. Required {}. Got {}.".format(
- required_schema_version,
- actual_version,
- ),
- )
-
- cursor.execute(
- # A denormalized schema because, for now, it's simpler. :/
- """
- CREATE TABLE IF NOT EXISTS [vouchers] (
- [number] text,
- [created] text, -- An ISO8601 date+time string.
- [state] text DEFAULT "pending", -- pending, double-spend, redeemed
-
- [finished] text DEFAULT NULL, -- ISO8601 date+time string when
- -- the current terminal state was entered.
-
- [token-count] num DEFAULT NULL, -- Set in the redeemed state to the number
- -- of tokens received on this voucher's
- -- redemption.
-
- PRIMARY KEY([number])
- )
- """,
- )
- cursor.execute(
- """
- CREATE TABLE IF NOT EXISTS [tokens] (
- [text] text, -- The random string that defines the token.
- [voucher] text, -- Reference to the voucher these tokens go with.
-
- PRIMARY KEY([text])
- FOREIGN KEY([voucher]) REFERENCES [vouchers]([number])
- )
- """,
- )
- cursor.execute(
- """
- CREATE TABLE IF NOT EXISTS [unblinded-tokens] (
- [token] text, -- The base64 encoded unblinded token.
-
- PRIMARY KEY([token])
- )
- """,
- )
- 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])
- )
- """,
- )
+ actual_version = get_schema_version(cursor)
+ schema_upgrades = list(get_schema_upgrades(actual_version))
+ run_schema_upgrades(schema_upgrades, cursor)
return conn
@@ -280,7 +198,6 @@ class VoucherStore(object):
db_path = FilePath(node_config.get_private_path(CONFIG_DB_NAME))
conn = open_and_initialize(
db_path,
- required_schema_version=1,
connect=connect,
)
return cls(
diff --git a/src/_zkapauthorizer/schema.py b/src/_zkapauthorizer/schema.py
new file mode 100644
index 0000000000000000000000000000000000000000..cf71a9c2a9d11b26ba4756e505284770a6952dd3
--- /dev/null
+++ b/src/_zkapauthorizer/schema.py
@@ -0,0 +1,134 @@
+# Copyright 2019 PrivateStorage.io, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import (
+ unicode_literals,
+)
+
+"""
+This module defines the database schema used by the model interface.
+"""
+
+def get_schema_version(cursor):
+ cursor.execute(
+ """
+ CREATE TABLE IF NOT EXISTS [version] AS SELECT 0 AS [version]
+ """
+ )
+ cursor.execute(
+ """
+ SELECT [version] FROM [version]
+ """
+ )
+ [(actual_version,)] = cursor.fetchall()
+ return actual_version
+
+
+def get_schema_upgrades(from_version):
+ """
+ Generate unicode strings containing SQL expressions to alter a schema from
+ ``from_version`` to the latest version.
+
+ :param int from_version: The version of the schema which may require
+ upgrade.
+ """
+ while from_version in _UPGRADES:
+ for upgrade in _UPGRADES[from_version]:
+ yield upgrade
+ yield _INCREMENT_VERSION
+ from_version += 1
+
+
+def run_schema_upgrades(upgrades, cursor):
+ """
+ Apply the given upgrades using the given cursor.
+
+ :param list[unicode] upgrades: The SQL statements to apply for the
+ upgrade.
+
+ :param cursor: A DB-API cursor to use to run the SQL.
+ """
+ for upgrade in upgrades:
+ cursor.execute(upgrade)
+
+
+_INCREMENT_VERSION = (
+ """
+ UPDATE [version]
+ SET [version] = [version] + 1
+ """
+)
+
+# A mapping from old schema versions to lists of unicode strings of SQL to
+# execute against that version of the schema to create the successor schema.
+_UPGRADES = {
+ 0: [
+ """
+ CREATE TABLE [vouchers] (
+ [number] text,
+ [created] text, -- An ISO8601 date+time string.
+ [state] text DEFAULT "pending", -- pending, double-spend, redeemed
+
+ [finished] text DEFAULT NULL, -- ISO8601 date+time string when
+ -- the current terminal state was entered.
+
+ [token-count] num DEFAULT NULL, -- Set in the redeemed state to the number
+ -- of tokens received on this voucher's
+ -- redemption.
+
+ PRIMARY KEY([number])
+ )
+ """,
+ """
+ CREATE TABLE [tokens] (
+ [text] text, -- The random string that defines the token.
+ [voucher] text, -- Reference to the voucher these tokens go with.
+
+ PRIMARY KEY([text])
+ FOREIGN KEY([voucher]) REFERENCES [vouchers]([number])
+ )
+ """,
+ """
+ CREATE TABLE [unblinded-tokens] (
+ [token] text, -- The base64 encoded unblinded token.
+
+ PRIMARY KEY([token])
+ )
+ """,
+ """
+ CREATE TABLE [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])
+ )
+ """,
+ ],
+}
+
+def _check_consistency():
+ if _UPGRADES.keys() != range(len(_UPGRADES)):
+ raise TypeError("Inconsistent schema versions in schema upgraders.")
+
+_check_consistency()
diff --git a/src/_zkapauthorizer/tests/test_model.py b/src/_zkapauthorizer/tests/test_model.py
index 9ea41591dfadd3eac428726d22856fead977f00b..bf2dbaf7e3c4849ef8c8159450cb01ee7dca45ad 100644
--- a/src/_zkapauthorizer/tests/test_model.py
+++ b/src/_zkapauthorizer/tests/test_model.py
@@ -68,16 +68,12 @@ from hypothesis.strategies import (
from twisted.python.runtime import (
platform,
)
-from twisted.python.filepath import (
- FilePath,
-)
from ..storage_common import (
BYTES_PER_PASS,
)
from ..model import (
- SchemaError,
StoreOpenError,
VoucherStore,
Voucher,
@@ -85,7 +81,6 @@ from ..model import (
DoubleSpend,
Redeemed,
LeaseMaintenanceActivity,
- open_and_initialize,
memory_connect,
)
@@ -107,22 +102,6 @@ class VoucherStoreTests(TestCase):
"""
Tests for ``VoucherStore``.
"""
- def test_create_mismatched_schema(self):
- """
- ``open_and_initialize`` raises ``SchemaError`` if asked for a database
- with a schema version other than it can create.
- """
- tempdir = self.useFixture(TempDir())
- dbpath = tempdir.join(b"db.sqlite3")
- self.assertThat(
- lambda: open_and_initialize(
- FilePath(dbpath),
- required_schema_version=100,
- ),
- raises(SchemaError),
- )
-
-
@given(tahoe_configs(), datetimes(), vouchers())
def test_get_missing(self, get_config, now, voucher):
"""