def test_cycles_simple():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_edge("A", "B")
network.add_edge("B", "A")
assert chash(network.cycles()) == chash([("A", "B", "A")])
def import_directory(self, datadir):
""" import a JSON directory into the database """
# id: json
data_by_id = {}
# hash(json): id
seen_hashes = {}
# load all json, mapped by json_id
for fname in glob.glob(os.path.join(datadir, self._type + '_*.json')):
with open(fname) as f:
data = json.load(f)
json_id = data.pop('_id')
objhash = omnihash(data)
if objhash not in seen_hashes:
seen_hashes[objhash] = json_id
data_by_id[json_id] = data
else:
self.duplicates[json_id] = seen_hashes[objhash]
# toposort the nodes so parents are imported first
network = Network()
in_network = set()
import_order = []
for json_id, data in data_by_id.items():
parent_id = data.get('parent_id', None)
if parent_id:
# Right. There's an import dep. We need to add the edge from
# the parent to the current node, so that we import the parent
# before the current node.
network.add_edge(parent_id, json_id)
else:
# Otherwise, there is no parent, and we just need to add it to
# the network to add whenever we feel like it during the import
# phase.
network.add_node(json_id)
# resolve the sorted import order
for jid in network.sort():
import_order.append((jid, data_by_id[jid]))
in_network.add(jid)
# ensure all data made it into network
if in_network != set(data_by_id.keys()):
raise Exception("import is missing nodes in network set")
# time to actually do the import
for json_id, data in import_order:
parent_id = data.get('parent_id', None)
if parent_id:
# If we've got a parent ID, let's resolve it's JSON id
# (scrape-time) to a Database ID (needs to have had the
# parent imported first - which we asserted is true via
# the topological sort)
data['parent_id'] = self.resolve_json_id(parent_id)
obj, what = self.import_json(data)
self.json_to_db_id[json_id] = obj.id
self.results[what] += 1
return {self._type: self.results}
def test_cyclic_graph_error_simple():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_edge("A", "B")
network.add_edge("B", "A")
with pytest.raises(CyclicGraphError):
list(network.sort())
def test_dot_debug():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_edge("A", "B")
dot = network.dot()
assert dot == "digraph graphname {A -> B;}"
def test_sort_order_basic():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_node("C")
network.add_edge("A", "B")
network.add_edge("B", "C")
assert (list(network.sort())) == ["A", "B", "C"]
def test_cyclic_graph_error_massive():
network = Network()
entries = ["A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "A"]
for i, e in enumerate(entries[:-1]):
network.add_node(e)
network.add_edge(e, entries[1 + i])
with pytest.raises(CyclicGraphError):
list(network.sort())
def test_link_before_nodes():
network = Network()
network.add_edge("A", "B")
network.add_edge("B", "C")
network.add_edge("C", "D")
network.add_node("A")
network.add_node("B")
network.add_node("C")
network.add_node("D")
assert list(network.sort()) == ["A", "B", "C", "D"]
def test_sort_order_double():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_node("C")
network.add_edge("A", "B")
network.add_edge("A", "C")
network.add_edge("C", "B")
# A => B
# /
# A => C
assert (list(network.sort())) == ["A", "C", "B"]
def test_sort_order_staged():
network = Network()
network.add_node("A1")
network.add_node("A2")
network.add_node("A3")
network.add_edge("A1", "A2")
network.add_edge("A1", "A3")
network.add_edge("A2", "A3")
network.add_node("B1")
network.add_node("B2")
network.add_node("B3")
network.add_edge("B1", "B2")
network.add_edge("B1", "B3")
network.add_edge("B2", "B3")
network.add_edge("B1", "A1")
network.add_node("C1")
network.add_node("C2")
network.add_node("C3")
network.add_edge("C1", "C2")
network.add_edge("C1", "C3")
network.add_edge("C2", "C3")
network.add_edge("C1", "A1")
network.add_edge("C1", "B1")
network.add_edge("C1", "B1")
network.add_edge("B1", "A1")
network.add_edge("A1", "C2")
network.add_edge("A1", "C3")
# with open("/home/tag/debug.dot", 'w') as fd:
# fd.write(network.dot())
sorted_order = list(network.sort())
assert sorted_order.pop(0) == "C1"
assert sorted_order.pop(0) == "B1"
assert sorted_order.pop(0) in ("A1", "B2")
# ^^ This makes more sense after you dot debug it
assert sorted_order.pop(0) in ("A1", "B2")
def test_cycles_complex():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_node("C")
network.add_node("D")
network.add_edge("A", "B")
network.add_edge("B", "C")
network.add_edge("C", "D")
network.add_edge("D", "A")
network.add_edge("D", "C")
network.add_edge("C", "B")
network.add_edge("B", "D")
# with open("/home/tag/debug.dot", 'w') as fd:
# fd.write(network.dot())
assert chash(network.cycles()) == chash([
('B', 'C', 'B'),
('C', 'D', 'C'),
('A', 'B', 'D', 'A')
])
def test_internal_node_removal():
network = Network()
network.add_node("A")
network.add_node("B")
network.add_node("C")
network.add_node("D")
network.add_edge("A", "B")
network.add_edge("B", "C")
network.add_edge("C", "D")
network.add_edge("A", "C") # Useful for ensuring the ending list
# is deterministic.
# Ensure that we can't remove an internal node without a ValueError
# by default.
with pytest.raises(ValueError):
network.prune_node("B")
# OK. Now that we know that works, let's prune it harder.
network.prune_node("B", remove_backrefs=True)
# And make sure "B" is gone.
assert list(network.sort()) == ["A", "C", "D"]