Fix GraphState.to_json() for tuple-like nodes

abp/fancy.py

@@ -39,7 +39,7 @@ class GraphState(graphstate.GraphState, networkx.Graph):
 
         # Send data to browser and rate-limit
         try:
-            self.ws.send(json.dumps(self.to_json(), default = str))
+            self.ws.send(json.dumps(self.to_json(stringify=True)))
             self.ws.recv()
             time.sleep(delay)
         except websocket._exceptions.WebSocketTimeoutException:

abp/graphstate.py

@@ -6,6 +6,7 @@ import itertools as it
 import json
 import qi, clifford, util
 import random
+from util import ABPJsonEncoder
 
 
 class GraphState(object):
@@ -177,9 +178,19 @@ class GraphState(object):
         nbstr = str(self.adj)
         return "graph:\n node: {}\n adj: {}\n".format(node, nbstr)
 
-    def to_json(self):
-        """ Convert the graph to JSON form """
-        return {"node": self.node, "adj": self.adj}
+    def to_json(self, stringify = False):
+        """ 
+        Convert the graph to JSON form.
+        JSON keys must be strings, But sometimes it is useful to have 
+        a JSON-like object whose keys are tuples!
+        """
+        if stringify:
+            node = {str(key):value for key, value in self.node.items()}
+            adj = {str(key): {str(key):value for key, value in ngbh.items()} 
+                    for key, ngbh in self.adj.items()}
+            return {"node": node, "adj": adj}
+        else: 
+            return {"node": self.node, "adj": self.adj}
 
     def from_json(self, data):
         """ Reconstruct from JSON """

abp/util.py

@@ -2,5 +2,19 @@
 Utility functions for ABP
 """
 
+import json
+
 def xyz(x, y, z=0):
     return {"x": x, "y": y, "z": z}
+
+class ABPJsonEncoder(json.JSONEncoder):
+    def default(self, thing):
+        print thing
+
+if __name__ == '__main__':
+    j = ABPJsonEncoder()
+    print j.encode({1:2})
+    j = ABPJsonEncoder()
+    print j.encode({1:2})
+    print j.encode({(1,2):2})
+

tests/test_json.py

@@ -1,4 +1,4 @@
-from abp import GraphState
+from abp import GraphState, fancy
 from abp import clifford
 from demograph import demograph
 import time
@@ -12,11 +12,13 @@ def test_json_basic():
     assert "node" in js
     e = GraphState()
 
-#TODO
-def _test_to_json():
-    """ Nah """
-    assert e != g
-    e.from_json(js)
-    assert e == g
+def test_tuple_keys():
+    """ Test that we can write tuple-ish keys """
+    g = fancy.GraphState()
+    g.add_node("string")
+    g.add_node((1, 2, 3))
+    g.add_edge((1, 2, 3), "string")
+    print json.dumps(g.to_json(True))
+