Add benchmark script.

Author: dnephin

bench.py

@@ -0,0 +1,74 @@
+#!/usr/env/bin python
+"""
+Benchmark the performance of jsonschema.
+
+Example benchmark:
+
+    wget http://swagger.io/v2/schema.json
+    wget http://petstore.swagger.io/v2/swagger.json
+    python bench.py -r 5 schema.json swagger.json
+
+"""
+from __future__ import print_function
+import argparse
+import cProfile
+import json
+import time
+
+import jsonschema
+
+
+def parse_args():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('schema', help="path to a schema used to benchmark")
+    parser.add_argument('document', help="document to validate with schema")
+    parser.add_argument('-r', '--repeat', type=int, help="number of iterations")
+    parser.add_argument('--profile',
+                        help="Enable profiling, write profile to this filepath")
+    return parser.parse_args()
+
+
+def run(filename, schema, document):
+    resolver = jsonschema.RefResolver(
+        'file://{0}'.format(filename),
+        schema,
+        store={schema['id']: schema})
+    jsonschema.validate(document, schema, resolver=resolver)
+
+
+def format_time(time_):
+    return "%.3fms" % (time_ * 1000)
+
+
+def run_timeit(schema_filename, document_filename, repeat, profile):
+    with open(schema_filename) as schema_file:
+        schema = json.load(schema_file)
+
+    with open(document_filename) as fh:
+        document = json.load(fh)
+
+    if profile:
+        profiler = cProfile.Profile()
+        profiler.enable()
+
+    times = []
+    for _ in range(repeat):
+        start_time = time.time()
+        run(schema_filename, schema, document)
+        times.append(time.time() - start_time)
+
+    if profile:
+        profiler.disable()
+        profiler.dump_stats(profile)
+
+    print(", ".join(map(format_time, sorted(times))))
+    print("Mean: {0}".format(format_time(sum(times) / repeat)))
+
+
+def main():
+    args = parse_args()
+    run_timeit(args.schema, args.document, args.repeat, args.profile)
+
+
+if __name__ == "__main__":
+    main()