rewrite the project as a static site generator

this removes Flask, reworks a number of library methods accordingly, and
adds generators and build commands to process the instance directory
(largely unchanged, except config.py is now config.json) and spit out
files suitable to be served by a web server such as Nginx.

there are probably some rough edges here, but overall this works.

also note, as this is no longer server software on a network, the
license has changed from AGPLv3 to GPLv3, and the "or any later version"
allowance has been removed

Signed-off-by: Brian S. Stephan <bss@incorporeal.org>

tests/test_feed.py

@@ -1,44 +1,77 @@
 """Test the feed methods.
 
 SPDX-FileCopyrightText: © 2023 Brian S. Stephan <bss@incorporeal.org>
-SPDX-License-Identifier: AGPL-3.0-or-later
+SPDX-License-Identifier: GPL-3.0-only
 """
-from incorporealcms.feed import serve_feed
+import os
+import tempfile
+
+from incorporealcms import init_instance
+from incorporealcms.feed import generate_feed
+
+HERE = os.path.dirname(os.path.abspath(__file__))
+
+init_instance(instance_path=os.path.join(HERE, 'instance'))
 
 
-def test_unknown_type_is_404(client):
-    """Test that requesting a feed type that doesn't exist is a 404."""
-    response = client.get('/feed/wat')
-    assert response.status_code == 404
+def test_atom_type_generated():
+    """Test that an ATOM feed can be generated."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        src_dir = os.path.join(HERE, 'instance')
+        generate_feed('atom', src_dir, tmpdir)
+
+        with open(os.path.join(tmpdir, 'feed', 'atom'), 'r') as feed_output:
+            data = feed_output.read()
+            assert '<?xml version=\'1.0\' encoding=\'UTF-8\'?>\n<feed xmlns="http://www.w3.org/2005/Atom">' in data
+            assert '<id>https://example.org/</id>' in data
+            assert '<email>admin@example.org</email>' in data
+            assert '<name>Test Name</name>' in data
+
+            # forced-no-title.md
+            assert '<title>example.org</title>' in data
+            assert '<link href="https://example.org/forced-no-title"/>' in data
+            assert '<id>tag:example.org,2023-12-01:/forced-no-title</id>' in data
+            assert '<content type="html">&lt;p&gt;some words are here&lt;/p&gt;</content>' in data
+
+            # more-metadata.md
+            assert '<title>title for the page - example.org</title>' in data
+            assert '<link href="https://example.org/more-metadata"/>' in data
+            assert '<id>tag:example.org,2025-03-16:/more-metadata</id>' in data
+            assert '<content type="html">&lt;p&gt;hello&lt;/p&gt;</content>' in data
 
 
-def test_atom_type_is_200(client):
-    """Test that requesting an ATOM feed is found."""
-    response = client.get('/feed/atom')
-    assert response.status_code == 200
-    assert 'application/atom+xml' in response.content_type
-    print(response.text)
+def test_rss_type_generated():
+    """Test that an RSS feed can be generated."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        src_dir = os.path.join(HERE, 'instance')
+        generate_feed('rss', src_dir, tmpdir)
+
+        with open(os.path.join(tmpdir, 'feed', 'rss'), 'r') as feed_output:
+            data = feed_output.read()
+            assert '<?xml version=\'1.0\' encoding=\'UTF-8\'?>\n<rss xmlns:atom="http://www.w3.org/2005/Atom"' in data
+            assert 'xmlns:content="http://purl.org/rss/1.0/modules/content/" version="2.0">' in data
+            assert '<link>https://example.org</link>' in data
+
+            # forced-no-title.md
+            assert '<title>example.org</title>' in data
+            assert '<link>https://example.org/forced-no-title</link>' in data
+            assert '<guid isPermaLink="false">tag:example.org,2023-12-01:/forced-no-title</guid>' in data
+            assert '<description>&lt;p&gt;some words are here&lt;/p&gt;</description>' in data
+            assert '<author>admin@example.org (Test Name)</author>' in data
+
+            # more-metadata.md
+            assert '<title>title for the page - example.org</title>' in data
+            assert '<link>https://example.org/more-metadata</link>' in data
+            assert '<guid isPermaLink="false">tag:example.org,2025-03-16:/more-metadata</guid>' in data
+            assert '<description>&lt;p&gt;hello&lt;/p&gt;</description>' in data
+            assert '<author>admin@example.org (Test Name)</author>' in data
 
 
-def test_rss_type_is_200(client):
-    """Test that requesting an RSS feed is found."""
-    response = client.get('/feed/rss')
-    assert response.status_code == 200
-    assert 'application/rss+xml' in response.content_type
-    print(response.text)
-
-
-def test_feed_generator_atom(app):
-    """Test the root feed generator."""
-    with app.test_request_context():
-        content = serve_feed('atom')
-    assert b'<id>https://example.com/</id>' in content.data
-    assert b'<email>admin@example.com</email>' in content.data
-    assert b'<name>Test Name</name>' in content.data
-
-
-def test_feed_generator_rss(app):
-    """Test the root feed generator."""
-    with app.test_request_context():
-        content = serve_feed('rss')
-    assert b'<author>admin@example.com (Test Name)</author>' in content.data
+def test_multiple_runs_without_error():
+    """Test that we can run the RSS and Atom feed generators in any order."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        src_dir = os.path.join(HERE, 'instance')
+        generate_feed('atom', src_dir, tmpdir)
+        generate_feed('rss', src_dir, tmpdir)
+        generate_feed('atom', src_dir, tmpdir)
+        generate_feed('rss', src_dir, tmpdir)