Separate out argument parsing and sanitising from actual feed construction logic.

gemfeed.py

@@ -90,11 +90,52 @@ def populate_entry_from_file(filename, base_url, entry):
     title = extract_first_heading(filename, filename)
     entry.title(title)
 
+def build_feed(base_url, output="atom.xml", n=10, title="", subtitle="", author="", email=""):
+    """
+    Build an Atom feed for all world readable Gemini files in the current
+    directory, and write it to atom.xml.
+    """
+    # If a title hasn't been provided, try to get one from an index page
+    if not title:
+        title = get_feed_title()
+
+    # Setup feed
+    feed = FeedGenerator()
+    feed.id(base_url)
+    feed.title(title)
+    if subtitle:
+        feed.subtitle(subtitle)
+    author_details = {}
+    if author:
+        author_details["name"] = author
+    if email:
+        author_details["email"] = email
+    if author_details:
+        feed.author(author_details)
+    feed.link(href=base_url, rel='alternate')
+    feed.link(href=urljoin(base_url, output), rel='self')
+
+    # Add one entry per .gmi file
+    files = find_files(n)
+    if not files:
+        print("No world-readable Gemini content found! :(")
+        return
+    for n, filename in enumerate(files):
+        entry = feed.add_entry()
+        populate_entry_from_file(filename, base_url, entry)
+        print("Adding {} with title '{}'...".format(filename, entry.title()))
+        if n == 0:
+            feed.updated(entry.updated())
+
+    # Write file
+    feed.atom_file(output, pretty=True)
+    print("Wrote Atom feed to {}.".format(output))
+
 def main():
-
-    # Get default title from index page, if there is one
-    feed_title = get_feed_title()
-
+    """
+    Parse command line arguments, do some minor processing, and then invoke
+    the build_feed command with the provided settings.
+    """
     # Parse arguments
     parser = argparse.ArgumentParser(description='Generate an Atom feed for Gemini content.')
     parser.add_argument('-a', '--author', dest='author', type=str,
@@ -110,7 +151,7 @@ def main():
     parser.add_argument('-s', '--subtitle', dest='subtitle', type=str,
             help='feed subtitle')
     parser.add_argument('-t', '--title', dest='title', type=str,
-            default=feed_title, help='feed title')
+            help='feed title')
     args = parser.parse_args()
 
     # Normalise base URL
@@ -121,38 +162,9 @@ def main():
     base_url = base_url._replace(scheme="gemini")
     args.base_url = urllib.parse.urlunsplit(base_url)
 
-    # Setup feed
-    feed = FeedGenerator()
-    feed.id(args.base_url)
-    feed.title(args.title)
-    if args.subtitle:
-        feed.subtitle(args.subtitle)
-    author = {}
-    if args.author:
-        author["name"] = args.author
-    if args.email:
-        author["email"] = args.email
-    if author:
-        feed.author(author)
-    feed.link(href=args.base_url, rel='alternate')
-    feed.link(href=urljoin(args.base_url, args.output), rel='self')
-
-    # Add one entry per .gmi file
-    files = find_files(args.n)
-    if not files:
-        print("No world-readable Gemini content found! :(")
-        return
-
-    for n, filename in enumerate(files):
-        entry = feed.add_entry()
-        populate_entry_from_file(filename, args.base_url, entry)
-        print("Adding {} with title '{}'...".format(filename, entry.title()))
-        if n == 0:
-            feed.updated(entry.updated())
-
-    # Write file
-    feed.atom_file(args.output, pretty=True)
-    print("Wrote Atom feed to {}.".format(args.output))
+    # Build the feed
+    build_feed(args.base_url, args.output, args.n, args.title, args.subtitle,
+            args.author, args.email)
 
 if __name__ == "__main__":
     main()