Add command-line arguments to change default input and output files

polygraph.py

@@ -2,6 +2,7 @@
 
 import pygraphviz as pgv
 import json
+import argparse
 
 # These are the attributes to use for color-coding the graphs
 # fixme: make these configurable
@@ -27,9 +28,18 @@ relationship_colors = {
     }
 
 
+def parse_args():
+    parser = argparse.ArgumentParser(description='Generate graphs of polyamorous family networks from data files')
+    parser.add_argument('--input', '-i', default='network.json', help='Input file in json format')
+    parser.add_argument('--output', '-o', default='network.png', help='Output image file. Format auto-detected from file extension')
+    return parser.parse_args()
+
+
 def main():
+    settings = parse_args()
+
     try:
-        data = json.load(open('network.dat', 'r'))
+        data = json.load(open(settings.input, 'r'))
     except Exception as e:
         print "Error parsing data file: " + str(e)
         return
@@ -48,7 +58,7 @@ def main():
         graph.add_edge(member1, member2, style=fluid_colors[fluid], color=relationship_colors[rel])
 
     graph.layout()
-    graph.draw('poly_network.png')
+    graph.draw(settings.output)
     
 
 if __name__ == '__main__': main()