def test_infinite_loop(self):
"""
Tests a complex dependency graph:
app_a: 0001 <-
\
app_b: 0001 <- x 0002 <-
/ \
app_c: 0001<- <------------- x 0002
And apply sqashing on app_c.
"""
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_node(("app_c", "0001_squashed_0002"), None)
graph.add_dependency("app_b.0001", ("app_b", "0001"), ("app_c", "0001_squashed_0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_a", "0001"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
graph.add_dependency("app_c.0001_squashed_0002", ("app_c", "0001_squashed_0002"), ("app_b", "0002"))
with self.assertRaises(CircularDependencyError):
graph.forwards_plan(("app_c", "0001_squashed_0002"))
def test_infinite_loop(self):
"""
Tests a complex dependency graph:
app_a: 0001 <-
\
app_b: 0001 <- x 0002 <-
/ \
app_c: 0001<- <------------- x 0002
And apply squashing on app_c.
"""
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_node(("app_c", "0001_squashed_0002"), None)
graph.add_dependency("app_b.0001", ("app_b", "0001"),
("app_c", "0001_squashed_0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"),
("app_a", "0001"))
graph.add_dependency("app_b.0002", ("app_b", "0002"),
("app_b", "0001"))
graph.add_dependency("app_c.0001_squashed_0002",
("app_c", "0001_squashed_0002"),
("app_b", "0002"))
with self.assertRaises(CircularDependencyError):
graph.forwards_plan(("app_c", "0001_squashed_0002"))
def test_complex_graph(self):
"""
Tests a complex dependency graph:
app_a: 0001 <-- 0002 <--- 0003 <-- 0004
\ \ / /
app_b: 0001 <-\ 0002 <-X /
\ \ /
app_c: \ 0001 <-- 0002 <-
"""
# Build graph
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_a", "0002"), None)
graph.add_node(("app_a", "0003"), None)
graph.add_node(("app_a", "0004"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_node(("app_c", "0001"), None)
graph.add_node(("app_c", "0002"), None)
graph.add_dependency("app_a.0004", ("app_a", "0004"), ("app_a", "0003"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_a", "0002"))
graph.add_dependency("app_a.0002", ("app_a", "0002"), ("app_a", "0001"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_b", "0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
graph.add_dependency("app_a.0004", ("app_a", "0004"), ("app_c", "0002"))
graph.add_dependency("app_c.0002", ("app_c", "0002"), ("app_c", "0001"))
graph.add_dependency("app_c.0001", ("app_c", "0001"), ("app_b", "0001"))
graph.add_dependency("app_c.0002", ("app_c", "0002"), ("app_a", "0002"))
# Test branch C only
self.assertEqual(
graph.forwards_plan(("app_c", "0002")),
[('app_b', '0001'), ('app_c', '0001'), ('app_a', '0001'), ('app_a', '0002'), ('app_c', '0002')],
)
# Test whole graph
self.assertEqual(
graph.forwards_plan(("app_a", "0004")),
[
('app_b', '0001'), ('app_c', '0001'), ('app_a', '0001'),
('app_a', '0002'), ('app_c', '0002'), ('app_b', '0002'),
('app_a', '0003'), ('app_a', '0004'),
],
)
# Test reverse to b:0001
self.assertEqual(
graph.backwards_plan(("app_b", "0001")),
[
('app_a', '0004'), ('app_c', '0002'), ('app_c', '0001'),
('app_a', '0003'), ('app_b', '0002'), ('app_b', '0001'),
],
)
# Test roots and leaves
self.assertEqual(
graph.root_nodes(),
[('app_a', '0001'), ('app_b', '0001'), ('app_c', '0001')],
)
self.assertEqual(
graph.leaf_nodes(),
[('app_a', '0004'), ('app_b', '0002'), ('app_c', '0002')],
)
def test_simple_graph(self):
"""
Tests a basic dependency graph:
app_a: 0001 <-- 0002 <--- 0003 <-- 0004
/
app_b: 0001 <-- 0002 <-/
"""
# Build graph
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_a", "0002"), None)
graph.add_node(("app_a", "0003"), None)
graph.add_node(("app_a", "0004"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_dependency("app_a.0004", ("app_a", "0004"), ("app_a", "0003"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_a", "0002"))
graph.add_dependency("app_a.0002", ("app_a", "0002"), ("app_a", "0001"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_b", "0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
# Test root migration case
self.assertEqual(
graph.forwards_plan(("app_a", "0001")),
[("app_a", "0001")],
)
# Test branch B only
self.assertEqual(
graph.forwards_plan(("app_b", "0002")),
[("app_b", "0001"), ("app_b", "0002")],
)
# Test whole graph
self.assertEqual(
graph.forwards_plan(("app_a", "0004")),
[
("app_b", "0001"),
("app_b", "0002"),
("app_a", "0001"),
("app_a", "0002"),
("app_a", "0003"),
("app_a", "0004"),
],
)
# Test reverse to b:0002
self.assertEqual(
graph.backwards_plan(("app_b", "0002")),
[("app_a", "0004"), ("app_a", "0003"), ("app_b", "0002")],
)
# Test roots and leaves
self.assertEqual(
graph.root_nodes(),
[("app_a", "0001"), ("app_b", "0001")],
)
self.assertEqual(
graph.leaf_nodes(),
[("app_a", "0004"), ("app_b", "0002")],
)
def test_circular_graph_2(self):
graph = MigrationGraph()
graph.add_node(('A', '0001'), None)
graph.add_node(('C', '0001'), None)
graph.add_node(('B', '0001'), None)
graph.add_dependency('A.0001', ('A', '0001'), ('B', '0001'))
graph.add_dependency('B.0001', ('B', '0001'), ('A', '0001'))
graph.add_dependency('C.0001', ('C', '0001'), ('B', '0001'))
with self.assertRaises(CircularDependencyError):
graph.forwards_plan(('C', '0001'))
def test_circular_graph_2(self):
graph = MigrationGraph()
graph.add_node(('A', '0001'), None)
graph.add_node(('C', '0001'), None)
graph.add_node(('B', '0001'), None)
graph.add_dependency('A.0001', ('A', '0001'), ('B', '0001'))
graph.add_dependency('B.0001', ('B', '0001'), ('A', '0001'))
graph.add_dependency('C.0001', ('C', '0001'), ('B', '0001'))
with self.assertRaises(CircularDependencyError):
graph.forwards_plan(('C', '0001'))
def test_plan_invalid_node(self):
"""
Tests for forwards/backwards_plan of nonexistent node.
"""
graph = MigrationGraph()
message = "Node ('app_b', '0001') not a valid node"
with self.assertRaisesMessage(NodeNotFoundError, message):
graph.forwards_plan(("app_b", "0001"))
with self.assertRaisesMessage(NodeNotFoundError, message):
graph.backwards_plan(("app_b", "0001"))
def test_plan_invalid_node(self):
"""
Tests for forwards/backwards_plan of nonexistent node.
"""
graph = MigrationGraph()
message = "Node ('app_b', '0001') not a valid node"
with self.assertRaisesMessage(NodeNotFoundError, message):
graph.forwards_plan(("app_b", "0001"))
with self.assertRaisesMessage(NodeNotFoundError, message):
graph.backwards_plan(("app_b", "0001"))
def test_simple_graph(self):
"""
Tests a basic dependency graph:
app_a: 0001 <-- 0002 <--- 0003 <-- 0004
/
app_b: 0001 <-- 0002 <-/
"""
# Build graph
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_a", "0002"), None)
graph.add_node(("app_a", "0003"), None)
graph.add_node(("app_a", "0004"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_dependency("app_a.0004", ("app_a", "0004"), ("app_a", "0003"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_a", "0002"))
graph.add_dependency("app_a.0002", ("app_a", "0002"), ("app_a", "0001"))
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_b", "0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
# Test root migration case
self.assertEqual(
graph.forwards_plan(("app_a", "0001")),
[('app_a', '0001')],
)
# Test branch B only
self.assertEqual(
graph.forwards_plan(("app_b", "0002")),
[("app_b", "0001"), ("app_b", "0002")],
)
# Test whole graph
self.assertEqual(
graph.forwards_plan(("app_a", "0004")),
[
('app_b', '0001'), ('app_b', '0002'), ('app_a', '0001'),
('app_a', '0002'), ('app_a', '0003'), ('app_a', '0004'),
],
)
# Test reverse to b:0002
self.assertEqual(
graph.backwards_plan(("app_b", "0002")),
[('app_a', '0004'), ('app_a', '0003'), ('app_b', '0002')],
)
# Test roots and leaves
self.assertEqual(
graph.root_nodes(),
[('app_a', '0001'), ('app_b', '0001')],
)
self.assertEqual(
graph.leaf_nodes(),
[('app_a', '0004'), ('app_b', '0002')],
)
def test_graph_iterative(self):
graph = MigrationGraph()
root = ("app_a", "1")
graph.add_node(root, None)
expected = [root]
for i in range(2, 1000):
parent = ("app_a", str(i - 1))
child = ("app_a", str(i))
graph.add_node(child, None)
graph.add_dependency(str(i), child, parent)
expected.append(child)
leaf = expected[-1]
with warnings.catch_warnings(record=True) as w:
warnings.simplefilter('always', RuntimeWarning)
forwards_plan = graph.forwards_plan(leaf)
self.assertEqual(len(w), 1)
self.assertTrue(issubclass(w[-1].category, RuntimeWarning))
self.assertEqual(str(w[-1].message), RECURSION_DEPTH_WARNING)
self.assertEqual(expected, forwards_plan)
with warnings.catch_warnings(record=True) as w:
warnings.simplefilter('always', RuntimeWarning)
backwards_plan = graph.backwards_plan(root)
self.assertEqual(len(w), 1)
self.assertTrue(issubclass(w[-1].category, RuntimeWarning))
self.assertEqual(str(w[-1].message), RECURSION_DEPTH_WARNING)
self.assertEqual(expected[::-1], backwards_plan)
def test_circular_graph(self):
"""
Tests a circular dependency graph.
"""
# Build graph
graph = MigrationGraph()
graph.add_node(("app_a", "0001"), None)
graph.add_node(("app_a", "0002"), None)
graph.add_node(("app_a", "0003"), None)
graph.add_node(("app_b", "0001"), None)
graph.add_node(("app_b", "0002"), None)
graph.add_dependency("app_a.0003", ("app_a", "0003"), ("app_a", "0002"))
graph.add_dependency("app_a.0002", ("app_a", "0002"), ("app_a", "0001"))
graph.add_dependency("app_a.0001", ("app_a", "0001"), ("app_b", "0002"))
graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
graph.add_dependency("app_b.0001", ("app_b", "0001"), ("app_a", "0003"))
# Test whole graph
with self.assertRaises(CircularDependencyError):
graph.forwards_plan(("app_a", "0003"), )
def test_graph_recursive(self):
graph = MigrationGraph()
root = ("app_a", "1")
graph.add_node(root, None)
expected = [root]
for i in range(2, 750):
parent = ("app_a", str(i - 1))
child = ("app_a", str(i))
graph.add_node(child, None)
graph.add_dependency(str(i), child, parent)
expected.append(child)
leaf = expected[-1]
forwards_plan = graph.forwards_plan(leaf)
self.assertEqual(expected, forwards_plan)
backwards_plan = graph.backwards_plan(root)
self.assertEqual(expected[::-1], backwards_plan)
def test_graph_recursive(self):
graph = MigrationGraph()
root = ("app_a", "1")
graph.add_node(root, None)
expected = [root]
for i in range(2, 750):
parent = ("app_a", str(i - 1))
child = ("app_a", str(i))
graph.add_node(child, None)
graph.add_dependency(str(i), child, parent)
expected.append(child)
leaf = expected[-1]
forwards_plan = graph.forwards_plan(leaf)
self.assertEqual(expected, forwards_plan)
backwards_plan = graph.backwards_plan(root)
self.assertEqual(expected[::-1], backwards_plan)
def test_iterative_dfs_complexity(self):
"""
In a graph with merge migrations, iterative_dfs() traverses each node
only once even if there are multiple paths leading to it.
"""
n = 50
graph = MigrationGraph()
for i in range(1, n + 1):
graph.add_node(("app_a", str(i)), None)
graph.add_node(("app_b", str(i)), None)
graph.add_node(("app_c", str(i)), None)
for i in range(1, n):
graph.add_dependency(None, ("app_b", str(i)), ("app_a", str(i)))
graph.add_dependency(None, ("app_c", str(i)), ("app_a", str(i)))
graph.add_dependency(None, ("app_a", str(i + 1)), ("app_b", str(i)))
graph.add_dependency(None, ("app_a", str(i + 1)), ("app_c", str(i)))
plan = graph.forwards_plan(("app_a", str(n)))
expected = [
(app, str(i)) for i in range(1, n) for app in ["app_a", "app_c", "app_b"]
] + [("app_a", str(n))]
self.assertEqual(plan, expected)
def test_graph_iterative(self):
graph = MigrationGraph()
root = ("app_a", "1")
graph.add_node(root, None)
expected = [root]
for i in range(2, 1000):
parent = ("app_a", str(i - 1))
child = ("app_a", str(i))
graph.add_node(child, None)
graph.add_dependency(str(i), child, parent)
expected.append(child)
leaf = expected[-1]
with self.assertWarnsMessage(RuntimeWarning, RECURSION_DEPTH_WARNING):
forwards_plan = graph.forwards_plan(leaf)
self.assertEqual(expected, forwards_plan)
with self.assertWarnsMessage(RuntimeWarning, RECURSION_DEPTH_WARNING):
backwards_plan = graph.backwards_plan(root)
self.assertEqual(expected[::-1], backwards_plan)
def test_graph_iterative(self):
graph = MigrationGraph()
root = ("app_a", "1")
graph.add_node(root, None)
expected = [root]
for i in range(2, 1000):
parent = ("app_a", str(i - 1))
child = ("app_a", str(i))
graph.add_node(child, None)
graph.add_dependency(str(i), child, parent)
expected.append(child)
leaf = expected[-1]
with self.assertWarnsMessage(RuntimeWarning, RECURSION_DEPTH_WARNING):
forwards_plan = graph.forwards_plan(leaf)
self.assertEqual(expected, forwards_plan)
with self.assertWarnsMessage(RuntimeWarning, RECURSION_DEPTH_WARNING):
backwards_plan = graph.backwards_plan(root)
self.assertEqual(expected[::-1], backwards_plan)
