Enable bidirectional route creation on synthetic routes (#29)

* udpate tests

* bidirectional check

* refactor for loop through directions

* udpate tests

peartree/graph.py

@@ -4,7 +4,7 @@
 import pandas as pd
 import partridge as ptg
 from fiona import crs
-from shapely.geometry import shape
+from shapely.geometry import LineString, Point, shape
 
 from .settings import WGS84
 from .summarizer import (generate_edge_and_wait_values,
@@ -211,37 +211,47 @@ def make_synthetic_system_network(
     sid_lookup = {}
     all_nodes = None
     for feat in reference_geojson['features']:
-        ref_shape = shape(feat['geometry'])
-
         # Pull out required properties
         props = feat['properties']
         headway = props['headway']
         avg_speed = props['average_speed']
         stop_dist = props['stop_distance_distribution']
 
-        # Generate reference geometry data
-        chunks = generate_meter_projected_chunks(ref_shape, stop_dist)
-        all_pts = generate_stop_points(chunks)
-
-        # Give each stop a unique id
-        stop_ids = generate_stop_ids(len(all_pts))
-
-        # Produce graph components
-        nodes = generate_nodes_df(stop_ids, all_pts, headway)
-        edges = generate_edges_df(stop_ids, all_pts, chunks, avg_speed)
-
-        # Mutates the G network object
-        sid_lookup_sub = _add_nodes_and_edges(G, name, nodes, edges)
-
-        # Update the parent sid with new values
-        for key, val in sid_lookup_sub.items():
-            sid_lookup[key] = val
-
-        # Then add to the running tally of nodes
-        if all_nodes is None:
-            all_nodes = nodes.copy()
-        else:
-            all_nodes = all_nodes.append(nodes)
+        ref_shape_1 = shape(feat['geometry'])
+        ref_shapes = [ref_shape_1]
+
+        # Check if want to do bidirectional (optional)
+        if 'bidirectional' in props and bool(props['bidirectional']):
+            coord_array = [Point(p) for p in ref_shape_1.coords]
+            ref_shape_2 = LineString(reversed(coord_array))
+            ref_shapes.append(ref_shape_2)
+
+        # For either the one specified direction or both, create
+        # and add imputed nodes and edges from supplied shape
+        for ref_shape in ref_shapes:
+            # Generate reference geometry data
+            chunks = generate_meter_projected_chunks(ref_shape, stop_dist)
+            all_pts = generate_stop_points(chunks)
+
+            # Give each stop a unique id
+            stop_ids = generate_stop_ids(len(all_pts))
+
+            # Produce graph components
+            nodes = generate_nodes_df(stop_ids, all_pts, headway)
+            edges = generate_edges_df(stop_ids, all_pts, chunks, avg_speed)
+
+            # Mutates the G network object
+            sid_lookup_sub = _add_nodes_and_edges(G, name, nodes, edges)
+
+            # Update the parent sid with new values
+            for key, val in sid_lookup_sub.items():
+                sid_lookup[key] = val
+
+            # Then add to the running tally of nodes
+            if all_nodes is None:
+                all_nodes = nodes.copy()
+            else:
+                all_nodes = all_nodes.append(nodes)
 
     # Generate cross feed edge values
     exempt_nodes = []

tests/test_paths.py

@@ -97,16 +97,30 @@ def test_synthetic_network():
     with open(geojson_path, 'r') as gjf:
         reference_geojson = json.load(gjf)
 
-    G = load_synthetic_network_as_graph(reference_geojson)
+    G1 = load_synthetic_network_as_graph(reference_geojson)
 
     # This fixture gets broken into 15 chunks, so 15 + 1 = 16
-    nodes = list(G.nodes())
+    nodes = list(G1.nodes())
     assert len(nodes) == 16
 
     # And since it is one-directional, it gets the same edges as chunks
-    edges = list(G.edges())
+    edges = list(G1.edges())
     assert len(edges) == 15
 
+    # Go back to the GeoJSON and set optional bidirectional flag
+    for i in range(len(reference_geojson['features'])):
+        reference_geojson['features'][i]['properties']['bidirectional'] = True
+
+    G2 = load_synthetic_network_as_graph(reference_geojson)
+
+    # This fixture gets broken into 15 chunks, so 15 + 1 = 16
+    nodes = list(G2.nodes())
+    assert len(nodes) == 16 * 2
+
+    # And since it is one-directional, it gets the same edges as chunks
+    edges = list(G2.edges())
+    assert len(edges) == 62
+
 
 def test_feed_to_graph_path():
     path_1 = fixture('caltrain-2017-07-24.zip')