rclone: add launchd mount/serve sidecar agents for Darwin

Adds the Darwin launchd mount/serve sidecar agents together with the
mount sidecar generation test.

modules/programs/rclone.nix

@@ -126,6 +126,61 @@ let
       ) "default.target";
     };
 
+  # Builder for a per-sidecar launchd agent. Returns the value half
+  # of a `nameValuePair` (the agent attrs).
+  mkLaunchdSidecar =
+    {
+      sidecarType,
+      remoteName,
+      sidecar,
+      sidecarPath,
+      isMount,
+      cmdName,
+    }:
+    let
+      label = "rclone-${cmdName}:${replaceIllegalChars sidecarPath}@${remoteName}";
+      runAtLoad = if isMount then sidecar.autoMount else sidecar.autoStart;
+      rcloneArgs =
+        [
+          (lib.getExe cfg.package)
+          cmdName
+        ]
+        ++ (lib.cli.toCommandLineGNU { } sidecar.options)
+        ++ (
+          if isMount then
+            [
+              "${remoteName}:${sidecarPath}"
+              sidecar.mountPoint
+            ]
+          else
+            [
+              sidecar.protocol
+              "${remoteName}:${sidecarPath}"
+            ]
+        );
+    in
+    {
+      enable = true;
+      config = {
+        ProgramArguments =
+          [ (lib.getExe rcloneSidecarWrapper) ]
+          ++ (lib.optionals isMount [
+            "--mkdir"
+            sidecar.mountPoint
+          ])
+          ++ rcloneArgs;
+        RunAtLoad = runAtLoad;
+        KeepAlive = {
+          SuccessfulExit = false;
+          Crashed = true;
+        };
+        StandardOutPath = "${config.home.homeDirectory}/Library/Logs/rclone/${label}.log";
+        StandardErrorPath = "${config.home.homeDirectory}/Library/Logs/rclone/${label}.err.log";
+        EnvironmentVariables =
+          if sidecar.logLevel != null then { RCLONE_LOG_LEVEL = sidecar.logLevel; } else null;
+      };
+    };
+
   # Iterate cfg.remotes × remote.${sidecarType}, applying the supplied
   # value builder. Produces an attrset keyed by service name.
   mkRcloneSidecars =
@@ -185,6 +240,11 @@ let
         sleep 1
       done
 
+      if [ "''${1:-}" = "--mkdir" ]; then
+        mkdir -p "$2"
+        shift 2
+      fi
+
       exec "$@"
     '';
   };
@@ -568,6 +628,8 @@ in
       ];
       launchd.agents = lib.mkMerge [
         mkLaunchdConfigService
+        (mkRcloneSidecars "mounts" mkLaunchdSidecar)
+        (mkRcloneSidecars "serve" mkLaunchdSidecar)
       ];
     };
 }

tests/modules/programs/rclone/default.nix

@@ -6,3 +6,6 @@
   rclone-mount-service-generation = ./mount-service-generation.nix;
   rclone-serve-service-generation = ./serve-service-generation.nix;
 }
+// lib.optionalAttrs pkgs.stdenv.hostPlatform.isDarwin {
+  rclone-mount-service-generation-darwin = ./mount-service-generation-darwin.nix;
+}

tests/modules/programs/rclone/mount-service-generation-darwin.nix

@@ -0,0 +1,67 @@
+_: {
+  programs.rclone = {
+    enable = true;
+    remotes.sftp-remote = {
+      config = {
+        type = "sftp";
+        host = "backup-server.example.com";
+        user = "alice";
+        key_file = "/Users/alice/.ssh/id_ed25519";
+      };
+      mounts = {
+        "documents/work" = {
+          enable = true;
+          mountPoint = "/Users/alice/mounts/work-docs";
+          logLevel = "INFO";
+          options = {
+            dir-cache-time = "5000h";
+            poll-interval = "10s";
+            umask = "002";
+          };
+        };
+        "disabled-mount" = {
+          enable = false;
+          mountPoint = "/Users/alice/mounts/disabled";
+        };
+      };
+    };
+  };
+
+  nmt.script = ''
+    plist="LaunchAgents/org.nix-community.home.rclone-mount:documents.work@sftp-remote.plist"
+    assertFileExists "$plist"
+
+    # rclone command line is wrapped by the launchd module in
+    # `/bin/sh -c "/bin/wait4path /nix/store && exec <args>"`,
+    # then by our rclone-sidecar-wrapper. Check for the meaningful
+    # substrings rather than the full quoted form.
+    assertFileContains "$plist" "rclone-sidecar-wrapper"
+    assertFileContains "$plist" "/bin/rclone"
+    assertFileContains "$plist" "mount"
+    assertFileContains "$plist" "&apos;--cache-dir=/home/hm-user/.cache/rclone&apos;"
+    assertFileContains "$plist" "&apos;--vfs-cache-mode=full&apos;"
+    assertFileContains "$plist" "&apos;--dir-cache-time=5000h&apos;"
+    assertFileContains "$plist" "&apos;--poll-interval=10s&apos;"
+    assertFileContains "$plist" "&apos;--umask=002&apos;"
+    assertFileContains "$plist" "sftp-remote:documents/work"
+    assertFileContains "$plist" "/Users/alice/mounts/work-docs"
+
+    # Mount sidecars pre-create the mount point via the wrapper's --mkdir flag.
+    assertFileContains "$plist" "rclone-sidecar-wrapper --mkdir"
+
+    # Lifecycle keys
+    assertFileContains "$plist" "<key>RunAtLoad</key>"
+    assertFileContains "$plist" "<key>KeepAlive</key>"
+    assertFileContains "$plist" "<key>Crashed</key>"
+
+    # Logs route under ~/Library/Logs/rclone/
+    assertFileContains "$plist" "Library/Logs/rclone"
+
+    # Log level surfaces as an environment variable
+    assertFileContains "$plist" "RCLONE_LOG_LEVEL"
+    assertFileContains "$plist" "INFO"
+
+    # Disabled mount produces no plist
+    assertPathNotExists "LaunchAgents/org.nix-community.home.rclone-mount:disabled-mount@sftp-remote.plist"
+  '';
+}