gpodder: synchronize feeds as part of desktop bringup -- not once per launch

hosts/common/programs/gpodder.nix

@@ -34,6 +34,12 @@ in {
 
     fs.".config/gpodderFeeds.opml".symlink.text = feeds.feedsToOpml wanted-feeds;
 
+    services.gpodder-ensure-feeds = {
+      description = "synchronize static OPML feeds into gPodder's subscription database";
+      partOf = [ "default" ];
+      startCommand = ''gpodder-ensure-feeds ''${HOME}/.config/gpodderFeeds.opml'';
+    };
+
     persist.byStore.plaintext = [
       "Videos/gPodder"
       # if you don't persist its database, you get untracked (and hence non-gc'd) downloads, plus slooow startup.

pkgs/by-name/gpodder-configured/gpodder-ensure-feeds

@@ -2,6 +2,7 @@
 #!nix-shell -i python3 -p gpodder -p listparser -p python3
 
 from dataclasses import dataclass, field
+from typing import Optional
 import argparse
 import listparser
 import subprocess
@@ -10,10 +11,10 @@ import sys
 @dataclass(repr=True)
 class Feed:
     url: str
-    title: str  # Optional
-    def __init__(self, url: str, title: str):
+    title: Optional[str]
+    def __init__(self, url: str, title: Optional[str]):
         self.url = url
-        self.title = title if title else None
+        self.title = title if title else None  # coerce title="" -> None
 
     def __eq__(self, other: "Feed") -> bool:
         return self.url == other.url and \
@@ -61,7 +62,7 @@ def partition_feeds(wanted: list[Feed], has: list[Feed]) -> Partitioned:
 def remove_feed(feed: Feed):
     subprocess.check_output(["gpo", "unsubscribe", feed.url])
 
-def remove_feeds(feeds: list[str]):
+def remove_feeds(feeds: list[Feed]):
     if not feeds:
         print("removing extra feeds: (none)")
         return
@@ -71,7 +72,7 @@ def remove_feeds(feeds: list[str]):
     for f in feeds:
         remove_feed(f)
 
-def add_feeds(opml_path: str, feeds: list[str]):
+def add_feeds(opml_path: str, feeds: list[Feed]):
     if not feeds:
         print("adding missing feeds: (none)")
         return

pkgs/by-name/gpodder-configured/package.nix

@@ -1,7 +1,12 @@
+# gpodder keeps all its feeds in a sqlite3 database.
+# the binary provided here, `gpodder-ensure-feeds`, may be run to import
+# my nix-synchronized feeds into gpodder, and remove any extras i've since deleted.
+# repeat imports are deduplicated by url, even when offline.
+# suggested usage: `gpodder-ensure-feeds ~/.config/gpodderFeeds.opml` as part of activation or some default .service
+
 {
   gpodder,
   listparser,
-  makeWrapper,
   static-nix-shell,
   symlinkJoin,
 }:
@@ -20,26 +25,6 @@ in
 (symlinkJoin {
   name = "${gpodder.pname}-configured";
   paths = [ gpodder remove-extra ];
-  nativeBuildInputs = [
-    makeWrapper
-  ];
-
-  # gpodder keeps all its feeds in a sqlite3 database.
-  # we can configure the feeds externally by wrapping gpodder and just instructing it to import
-  # a feedlist every time we run it.
-  # repeat imports are deduplicated by url, even when offline.
-  postBuild = ''
-    wrapProgram $out/bin/gpodder \
-      $extraMakeWrapperArgs \
-      --run "$out/bin/gpodder-ensure-feeds"' ~/.config/gpodderFeeds.opml "$@" || true' \
-      --run 'while [[ -n "$1" && "$1" != -- && "$1" != --help ]]; do shift; done ; if [[ "$1" == --help ]]; then exit; elif [[ "$1" == -- ]]; then shift; fi'
-
-    # fix up the .desktop file to invoke our wrapped application
-    # (rather, invoke `gpodder` by PATH, which could be this, or an outer layer of wrapping)
-    orig_desktop=$(readlink $out/share/applications/gpodder.desktop)
-    unlink $out/share/applications/gpodder.desktop
-    sed "s:Exec=.*/gpodder:Exec=gpodder:" $orig_desktop > $out/share/applications/gpodder.desktop
-  '';
 
   passthru = {
     inherit gpodder remove-extra;