Ensure directories appear first in listings [RHELDST-21890]

Directories are generally expected to be listed first in directory
indexes. That was already working for yum and file repos, but wasn't the
case for kickstart repos due to their combination of different types of
content.

This commit applies a consistent sorting so that directories will always
come first, and entries will otherwise be sorted by name, for all repo
types.

repo_autoindex/_impl/base.py

@@ -56,6 +56,23 @@ class IndexEntry:
     padding: str = ""
     icon: str = ICON_OTHER
 
+    @property
+    def sort_key(self):
+        # Returns a suggested sort key for displaying entries in
+        # a UI.
+
+        priority = 0
+
+        # Folders should come first
+        if self.href.endswith("/"):
+            priority -= 1
+            # And special folders like ".." even earlier
+            if self.href.startswith("."):
+                priority -= 1
+
+        # Entries sort by the priority we calculated, and then by name
+        return (priority, self.href)
+
 
 class Repo(ABC):
     def __init__(

repo_autoindex/_impl/tree.py

@@ -70,4 +70,6 @@ def treeify(
                 ]
             )
 
+    out.entries.sort(key=lambda entry: entry.sort_key)
+
     return out

tests/test_kickstart_render_typical.py

@@ -1,4 +1,5 @@
 import io
+import re
 from typing import BinaryIO, Optional
 import textwrap
 
@@ -619,6 +620,30 @@ async def test_typical_index():
 
     assert '<a href="vmlinuz">' in by_relative_dir["images/pxeboot"].content
 
+    # Sample the order of entries in some of the listings.
+    # Directories are expected to come first.
+    links = re.findall(r'<a href="([^"]+)"', by_relative_dir[""].content)
+    assert links == [
+        "images/",
+        "packages/",
+        "repodata/",
+        "EULA",
+        "GPL",
+        "RPM-GPG-KEY-redhat-beta",
+        "RPM-GPG-KEY-redhat-release",
+        "extra_files.json",
+        "treeinfo",
+    ]
+
+    links = re.findall(r'<a href="([^"]+)"', by_relative_dir["images"].content)
+    assert links == [
+        "../",
+        "pxeboot/",
+        "boot.iso",
+        "efiboot.img",
+        "install.img",
+    ]
+
 
 async def test_typical_appstream_index():
     fetcher = StaticFetcher()