mutual_friends.py: switch to CSV/JSON output

1 files changed, 52 insertions, 12 deletions

diff --git a/mutual_friends.py b/mutual_friends.py
index 2f32038..3b86a8e 100644
--- a/mutual_friends.py
+++ b/mutual_friends.py
@@ -2,33 +2,73 @@
 # This file is licensed under the terms of the MIT License.
 # See LICENSE.txt for details.
 
+from collections import OrderedDict
+import csv
+from enum import Enum
+import json
+import sys
+
 import vk.api
-import vk.user
+from vk.user import Field
+
+def query_friend_list(api, user):
+    return api.friends_get(user.get_uid(), fields=Field.SCREEN_NAME)
+
+OUTPUT_FIELDS = Field.FIRST_NAME, Field.LAST_NAME, Field.SCREEN_NAME
+
+def extract_output_fields(user):
+    new_user = OrderedDict()
+    for field in OUTPUT_FIELDS:
+        new_user[str(field)] = user[field] if field in user else None
+    return new_user
 
-def query_friends(api, user):
-    return api.friends_get(user.get_uid(), fields=vk.user.Field.SCREEN_NAME)
+def print_mutual_friends_csv(mutual_friends):
+    writer = csv.writer(sys.stdout)
+    for user in mutual_friends:
+        user = extract_output_fields(user)
+        writer.writerow(user.values())
 
-def format_user(user):
-    if user.has_last_name():
-        return '{} {} ({})'.format(user.get_last_name(), user.get_first_name(), user.get_screen_name())
+def print_mutual_friends_json(mutual_friends):
+    print(json.dumps([extract_output_fields(user) for user in mutual_friends], indent=3))
+
+def print_mutual_friends(mutual_friends, output_format):
+    if output_format is OutputFormat.CSV:
+        print_mutual_friends_csv(mutual_friends)
+    elif output_format is OutputFormat.JSON:
+        print_mutual_friends_json(mutual_friends)
     else:
-        return '{} ({})'.format(user.get_first_name(), user.get_screen_name())
+        raise NotImplementedError('unsupported output format: ' + str(output_format))
+
+class OutputFormat(Enum):
+    CSV = 'csv'
+    JSON = 'json'
+
+    def __str__(self):
+        return self.value
 
 if __name__ == '__main__':
     import argparse
 
+    def output_format(s):
+        try:
+            return OutputFormat(s)
+        except ValueError:
+            raise argparse.ArgumentError()
+
     parser = argparse.ArgumentParser(
         description='Learn who your ex and her new boyfriend are both friends with.')
 
     parser.add_argument(metavar='UID', dest='uids', nargs='+',
                         help='user IDs or "screen names"')
+    parser.add_argument('-f', '--format', type=output_format,
+                        choices=tuple(x for x in OutputFormat),
+                        default=OutputFormat.CSV,
+                        help='specify output format')
     args = parser.parse_args()
 
     api = vk.api.API(vk.api.Language.EN)
-    users = api.users_get(args.uids, fields=vk.user.Field.SCREEN_NAME)
+    users = api.users_get(args.uids, fields=Field.SCREEN_NAME)
 
-    friend_lists = map(lambda user: frozenset(query_friends(api, user)), users)
+    friend_lists = map(lambda user: frozenset(query_friend_list(api, user)), users)
     mutual_friends = frozenset.intersection(*friend_lists)
-    if mutual_friends:
-        for friend in mutual_friends:
-            print(format_user(friend))
+    print_mutual_friends(mutual_friends, args.format)