def main(args):
parser = argparse.ArgumentParser()
parser.add_argument('output',
metavar='graph.pickle',
help='Ouput graph file')
parser.add_argument(
'--connection',
default='postgresql://*****:*****@localhost/osrm',
help='Postgres connection string. Default %(default)s')
parser.add_argument('--prune',
action='store_true',
help='Collapse redundant edges, prune tails')
parser.add_argument('--verbose',
action='store_true',
help='Increase logging level')
args = parser.parse_args()
logging.basicConfig(
level=logging.INFO if args.verbose else logging.WARNING)
log.info("Creating DB engine")
engine = create_engine(args.connection, echo=False)
log.info("Creating DB session")
Session = sessionmaker(bind=engine)
session = Session()
g = build_graph(session)
if args.prune:
log.info("Collapsing unidirectional strings")
pruned = graphtools.collapse_degree_2_vtxs(g)
log.info("Removed %i thru-nodes", pruned)
log.info("Collapsing bidirectional strings")
pruned = graphtools.collapse_bidirectional_streets(g)
log.info("Removed %i thru-nodes", pruned)
log.info("Snipping tails")
snipped = graphtools.delete_degree_1_vtxs(g)
log.info("Removed %i tails", snipped)
loners = graphtools.delete_degree_0_vtxs(g)
log.info("Removed %i loner-nodes (should be zero)", loners)
redundancies = graphtools.identify_rendudant_nodes(g)
log.info("Marked %i nodes as redundant", redundancies)
log.info("Saving graph to %s", args.output)
g.save(args.output)
def test_build_graph():
with test_db_session() as session:
# Make a y-shaped graph
node1 = OSRMNode(1, 1, 2, True, False)
node2 = OSRMNode(2, 3, 4, False, False)
node3 = OSRMNode(3, 5, 6, False, False)
node4 = OSRMNode(4, 7, 8, False, False)
session.add(node1)
session.add(node2)
session.add(node3)
session.add(node4)
# The source-sink nodes aren't necessarily
# in "forward" order.
edge_12 = OSRMEdge(2, 1, 5, 5, False)
edge_23 = OSRMEdge(2, 3, 5, 5, False)
edge_24 = OSRMEdge(4, 2, 5, 5, False)
session.add_all([edge_12, edge_23, edge_24])
session.commit()
# The combination of the hash + forward
# nature should define the edge frequency.
freq_12 = OSRMEdgeFrequencies(
edge=OSRMEdge.hash_edge(1, 2),
# 1->2
forward=True,
freq=12,
geom=None)
freq_21 = OSRMEdgeFrequencies(
edge=OSRMEdge.hash_edge(1, 2),
# 2->1
forward=False,
freq=21,
geom=None)
freq_34 = OSRMEdgeFrequencies(
edge=OSRMEdge.hash_edge(2, 3),
# 2-> 3
forward=True,
freq=32,
geom=None)
freq_24 = OSRMEdgeFrequencies(
edge=OSRMEdge.hash_edge(2, 4),
# This means 2->4
forward=True,
freq=24,
geom=None)
session.add_all([freq_12, freq_21, freq_34, freq_24])
session.commit()
results = session.query(OSRMEdgeFrequencies).all()
eq_(len(results), 4)
eq_(results[0].edgeobj.source, 2)
eq_(results[0].edgeobj.sink, 1)
graph = build_graph(session)
eq_(len(graph.vs), 4)
eq_(len(graph.es), 4)
assert (graph.is_directed)
eq_(set(graph.vs["osm_id"]), set([1, 2, 3, 4]))
eq_(len(graph.vs.select(osm_id=1)), 1)
vtx_1 = graph.vs.select(osm_id=1)[0]
eq_(vtx_1.indegree(), 1)
eq_(vtx_1.outdegree(), 1)
eq_(vtx_1.degree(), 2)
eq_(vtx_1.successors()[0]["osm_id"], 2)
eq_(vtx_1.predecessors()[0]["osm_id"], 2)
vtx_2 = graph.vs.select(osm_id=2)[0]
eq_(vtx_2.indegree(), 1)
eq_(vtx_2.outdegree(), 3)
eq_(vtx_2.degree(), 4)
# Check edge weights are correct
# vtx 0 is node 1
eq_(gt.output_weights(graph, 0), [12])
eq_(gt.output_weights(graph, 1), [21, 32, 24])