From cf340ca2774e3dd11e7f79ad38ae561ccb13ff58 Mon Sep 17 00:00:00 2001
From: Dominik Polakovics <dominik.polakovics@cloonar.com>
Date: Thu, 29 May 2025 00:38:12 +0200
Subject: [PATCH] feat: add set-nix-channel module to manage nix-channel
 automatically

---
 hosts/fw/configuration.nix                |  1 +
 hosts/fw/modules/set-nix-channel.nix      |  1 +
 hosts/mail/configuration.nix              |  1 +
 hosts/mail/modules/set-nix-channel.nix    |  1 +
 hosts/nb/configuration.nix                |  1 +
 hosts/nb/modules/set-nix-channel.nix      |  1 +
 hosts/web-arm/configuration.nix           |  1 +
 hosts/web-arm/modules/set-nix-channel.nix |  1 +
 utils/modules/set-nix-channel.nix         | 40 +++++++++++++++++++++++
 9 files changed, 48 insertions(+)
 create mode 120000 hosts/fw/modules/set-nix-channel.nix
 create mode 120000 hosts/mail/modules/set-nix-channel.nix
 create mode 120000 hosts/nb/modules/set-nix-channel.nix
 create mode 120000 hosts/web-arm/modules/set-nix-channel.nix
 create mode 100644 utils/modules/set-nix-channel.nix

diff --git a/hosts/fw/configuration.nix b/hosts/fw/configuration.nix
index 0401028..5bd0338 100644
--- a/hosts/fw/configuration.nix
+++ b/hosts/fw/configuration.nix
@@ -64,6 +64,7 @@
 
     # setup network
     ./modules/setupnetwork.nix
+    ./modules/set-nix-channel.nix # Automatically manage nix-channel from /var/bento/channel
 
 
     ./hardware-configuration.nix
diff --git a/hosts/fw/modules/set-nix-channel.nix b/hosts/fw/modules/set-nix-channel.nix
new file mode 120000
index 0000000..4fdabfe
--- /dev/null
+++ b/hosts/fw/modules/set-nix-channel.nix
@@ -0,0 +1 @@
+../../../utils/modules/set-nix-channel.nix
\ No newline at end of file
diff --git a/hosts/mail/configuration.nix b/hosts/mail/configuration.nix
index 91c0004..0bc9d7b 100644
--- a/hosts/mail/configuration.nix
+++ b/hosts/mail/configuration.nix
@@ -15,6 +15,7 @@
     ./utils/modules/promtail
     ./utils/modules/victoriametrics
     ./utils/modules/netdata.nix
+    ./modules/set-nix-channel.nix # Automatically manage nix-channel from /var/bento/channel
 
     ./hardware-configuration.nix
   ];
diff --git a/hosts/mail/modules/set-nix-channel.nix b/hosts/mail/modules/set-nix-channel.nix
new file mode 120000
index 0000000..4fdabfe
--- /dev/null
+++ b/hosts/mail/modules/set-nix-channel.nix
@@ -0,0 +1 @@
+../../../utils/modules/set-nix-channel.nix
\ No newline at end of file
diff --git a/hosts/nb/configuration.nix b/hosts/nb/configuration.nix
index 6d6ec60..6407546 100644
--- a/hosts/nb/configuration.nix
+++ b/hosts/nb/configuration.nix
@@ -42,6 +42,7 @@ in {
 
       # ./modules/steam.nix
       ./modules/fingerprint.nix
+      ./modules/set-nix-channel.nix # Automatically manage nix-channel from /var/bento/channel
 
       ./hardware-configuration.nix
 
diff --git a/hosts/nb/modules/set-nix-channel.nix b/hosts/nb/modules/set-nix-channel.nix
new file mode 120000
index 0000000..4fdabfe
--- /dev/null
+++ b/hosts/nb/modules/set-nix-channel.nix
@@ -0,0 +1 @@
+../../../utils/modules/set-nix-channel.nix
\ No newline at end of file
diff --git a/hosts/web-arm/configuration.nix b/hosts/web-arm/configuration.nix
index 44de2e2..ac3d270 100644
--- a/hosts/web-arm/configuration.nix
+++ b/hosts/web-arm/configuration.nix
@@ -23,6 +23,7 @@
     ./utils/modules/promtail
     ./utils/modules/borgbackup.nix
     ./utils/modules/netdata.nix
+    ./modules/set-nix-channel.nix # Automatically manage nix-channel from /var/bento/channel
 
     ./hardware-configuration.nix
 
diff --git a/hosts/web-arm/modules/set-nix-channel.nix b/hosts/web-arm/modules/set-nix-channel.nix
new file mode 120000
index 0000000..4fdabfe
--- /dev/null
+++ b/hosts/web-arm/modules/set-nix-channel.nix
@@ -0,0 +1 @@
+../../../utils/modules/set-nix-channel.nix
\ No newline at end of file
diff --git a/utils/modules/set-nix-channel.nix b/utils/modules/set-nix-channel.nix
new file mode 100644
index 0000000..22823ef
--- /dev/null
+++ b/utils/modules/set-nix-channel.nix
@@ -0,0 +1,40 @@
+# utils/modules/set-nix-channel.nix
+{ config, pkgs, ... }:
+
+{
+  systemd.services.set-nix-channel = {
+    description = "Set nix-channel from /var/bento/channel";
+    after = [ "network.target" ]; # Ensure network is up
+    wantedBy = [ "multi-user.target" ]; # Start on boot
+
+    serviceConfig = {
+      Type = "oneshot";
+      RemainAfterExit = true; # Consider the service "active" after successful run
+      User = "root";
+      ExecStart = pkgs.writeShellScript "set-nix-channel-script" ''
+        set -e # Exit immediately if a command exits with a non-zero status.
+        CHANNEL_FILE="/var/bento/channel"
+        CHANNEL_NAME="nixos"
+
+        if [ ! -f "$CHANNEL_FILE" ]; then
+          echo "Error: Channel file $CHANNEL_FILE not found." >&2
+          exit 1
+        fi
+
+        CHANNEL_URL=$(cat "$CHANNEL_FILE")
+
+        if [ -z "$CHANNEL_URL" ]; then
+          echo "Error: Channel file $CHANNEL_FILE is empty." >&2
+          exit 1
+        fi
+
+        # Attempt to remove existing channel to ensure clean state, ignore error if it doesn't exist
+        ${pkgs.nix}/bin/nix-channel --remove "$CHANNEL_NAME" || true
+        ${pkgs.nix}/bin/nix-channel --add "$CHANNEL_URL" "$CHANNEL_NAME"
+        ${pkgs.nix}/bin/nix-channel --update "$CHANNEL_NAME"
+
+        echo "Successfully set and updated channel '$CHANNEL_NAME' from $CHANNEL_FILE."
+      '';
+    };
+  };
+}
\ No newline at end of file