Adding support to output json instead of python dict

It's easier to parse json output than python dict.

.coveragerc

@@ -6,3 +6,5 @@ omit =
 exclude_lines =
     def console_script()
     except ImportError
+    except json.decoder.JSONDecodeError
+    if isinstance

haproxy/line.py

@@ -253,3 +253,4 @@ def handle_bad_http_request(self):
 
         if self.raw_http_request != '<BADREQ>':
             print('Could not process HTTP request {0}'.format(self.raw_http_request),)
+

haproxy/main.py

@@ -5,6 +5,8 @@
 from haproxy.logfile import Log
 
 import argparse
+import datetime
+import json
 import os
 import re
 
@@ -76,6 +78,8 @@ def create_parser():
         '--list-filters', action='store_true', help='Lists all filters available.'
     )
 
+    parser.add_argument('--json', action='store_true', help='Output results in json.')
+
     return parser
 
 
@@ -89,6 +93,7 @@ def parse_arguments(args):
         'log': None,
         'list_commands': None,
         'list_filters': None,
+        'json': None,
     }
 
     if args.list_commands:
@@ -122,6 +127,9 @@ def parse_arguments(args):
         _validate_arg_logfile(args.log)
         data['log'] = args.log
 
+    if args.json is not None:
+        data['json'] = args.json
+
     return data
 
 
@@ -185,6 +193,11 @@ def _validate_arg_logfile(filename):
         raise ValueError('filename {0} does not exist'.format(filepath))
 
 
+def json_dumps_converter(o):
+    if isinstance(o, datetime.datetime):
+        return o.__str__()
+
+
 def print_commands():
     """Prints all commands available from Log with their
     description.
@@ -219,7 +232,7 @@ def show_help(data):
     # make sure that if no arguments are passed the help is shown
     show = True
     for key in data:
-        if data[key] is not None and key != 'log':
+        if data[key] is not None and key not in ('log', 'json'):
             show = False
             break
 
@@ -266,13 +279,17 @@ def main(args):
 
     # run all commands
     for command in args['commands']:
-        string = 'command: {0}'.format(command)
-        print(string)
-        print('=' * len(string))
+        if args['json'] is False:
+            string = 'command: {0}'.format(command)
+            print(string)
+            print('=' * len(string))
 
         cmd = getattr(log_file, 'cmd_{0}'.format(command))
         result = cmd()
-        print(result)
+        if args['json'] is True:
+            print(json.dumps(result, default=json_dumps_converter))
+        else:
+            print(result)
 
     return log_file  # return the log_file object so that tests can inspect it
 

haproxy/tests/test_argparse.py

@@ -7,6 +7,7 @@
 from haproxy.main import VALID_FILTERS
 from tempfile import NamedTemporaryFile
 
+import json
 import os
 import sys
 import unittest
@@ -47,6 +48,13 @@ def tearDown(self):
             if filename.endswith('.pickle'):
                 os.remove('{0}/{1}'.format(path, filename))
 
+    def validate_json(self, jsons):
+        try:
+            json.loads(jsons)
+        except json.decoder.JSONDecodeError:
+            return False
+        return True
+
     def test_arg_parser_start_invalid(self):
         """Check that if a 'start' argument is not valid an exception is
         raised.
@@ -224,6 +232,19 @@ def test_arg_parser_list_filters_output(self):
             for filter_name in VALID_FILTERS:
                 self.assertIn(filter_name[7:], output_text)
 
+    def test_arg_parser_json(self):
+        """Test that list filters argument outputs what's expected."""
+        arguments = ['-l', 'haproxy/tests/files/small.log', '--json', '-c', 'counter']
+        data = parse_arguments(self.parser.parse_args(arguments))
+        test_output = NamedTemporaryFile(mode='w', delete=False)
+
+        with RedirectStdout(stdout=test_output):
+            main(data)
+
+        with open(test_output.name, 'r') as output_file:
+            output_text = output_file.read()
+        self.assertTrue(self.validate_json(output_text))
+
     def test_arg_parser_filters(self):
         """Check that the filter logic on haproxy.main.main works as expected.
         """

haproxy/tests/test_log_file.py

@@ -30,6 +30,7 @@ def test_from_main(self):
             'filters': None,
             'list_commands': False,
             'list_filters': False,
+            'json': False,
         }
         logfile = main(data)