Add support for different output modes, deprecating --only-url

Supported output modes are:
- headlines
- json
- only-url (replacing --only-url)

scripts/tinytinypy

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 
 import argparse
+from enum import Enum
 from getpass import getpass
 import json
 import os
@@ -13,14 +14,40 @@ from tinytinypy import Connection
 
 APP_NAME = "tinytinypy" # For default config directories
 
+
+class OutputMode(Enum):
+    # enum values
+    JSON = ('json', False)
+    ONLY_URL = ('only-url', False)
+    HEADLINES = ('headlines', False)
+    # helpers
+    @classmethod
+    def get_mode_names(cls):
+        return [e.mode_name for e in cls]
+    @classmethod
+    def parse_mode(cls, mode_name):
+        for e in cls:
+            if e.mode_name == mode_name:
+                return e
+    def __init__(self, mode_name, requires_content):
+        self.mode_name = mode_name
+        self.requires_content = requires_content
+    def __str__(self):
+        return self.mode_name
+
 def func_articles(server, args):
     filtered = {key: value for key, value in args.__dict__.items() if key in ["feed_id", "cat_id", "limit", "skip", "view_mode", "since_id", "include_nested", "order_by"]}
-    headlines = server.getHeadlines(**filtered)
-    if args.only_url:
+    headlines = server.getHeadlines(show_content=args.output_mode.requires_content, **filtered)
+    if args.output_mode == OutputMode.ONLY_URL:
         for h in headlines:
             print(h.url)
-    else:
+    elif args.output_mode == OutputMode.HEADLINES:
+        for h in headlines:
+            print(h.title)
+    elif args.output_mode == OutputMode.JSON:
         print(json.dumps([h.toJson() for h in headlines]))
+    else:
+        raise Exception(f'Not implemented output mode "{args.output_mode}"')
 
 def configure_parser():
     parser = argparse.ArgumentParser(description="Allows access to feeds and articles of a Tiny Tiny RSS instance using the API.")
@@ -38,7 +65,7 @@ def configure_parser():
     p.add_argument('--limit', dest='limit', type=int, help="Maximum count of articles")
     p.add_argument('--skip', '--offset', dest='skip', type=int, help="Skip this amount of feeds first")
     p.add_argument('--view-mode', '--filter', dest='view_mode', choices=['all_articles', 'unread', 'adaptive', 'marked', 'updated'], default='all_articles', help='Only show articles of certain type')
-    p.add_argument('--only-url', dest='only_url', action='store_true', help="Only output urls of articles instead of full article info")
+    p.add_argument('--output-mode', dest='output_mode', choices=OutputMode, type=OutputMode.parse_mode, default='json', help='Define how the received articles should be outputed, in most modes except json and *-full modes, one line equals a single article')
     return parser
 
 def parse(args):