add nodeinfo package

configuration.nix

@@ -3,10 +3,9 @@
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
 { config, pkgs, ... }:
-
+let
-{
+  nodeinfo = (import pkgs/nodeinfo.nix);
-
+in {
-
   disabledModules = [ "services/security/tor.nix" ];
 
   imports =
@@ -14,15 +13,18 @@
       ./modules/default.nix
       ./modules/tor.nix
       ./modules/onionnode.nix
-
+      ./modules/nodeinfo.nix
     ];
 
   networking.hostName = "nix-bitcoin"; # Define your hostname.
   time.timeZone = "UTC";
 
   environment.systemPackages = with pkgs; [
-     wget vim tmux bitcoin git nginx
+     wget vim tmux git nginx nodeinfo
   ];
+  nixpkgs.config.packageOverrides = pkgs: {
+    inherit nodeinfo;
+  };
 
   services.openssh.enable = true;
 

modules/nodeinfo.nix

@@ -0,0 +1,17 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  config = {
+    systemd.services.nodeinfo = {
+      description = "Get node info";
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        ExecStart = "${pkgs.bash}/bin/bash -c ${pkgs.nodeinfo}/bin/nodeinfo";
+        user = "root";
+        type = "oneshot";
+      };
+    };
+  };
+}

pkgs/nodeinfo.nix

@@ -0,0 +1,14 @@
+with import <nixpkgs> {}; # bring all of Nixpkgs into scope
+
+stdenv.mkDerivation {
+  name = "nodeinfo";
+  src = ./nodeinfo.sh;
+
+  unpackPhase = "true";
+  installPhase = ''
+    mkdir -p $out
+    mkdir -p $out/bin
+    chmod +wx $src
+    cp $src $out/bin/nodeinfo
+    '';
+}

pkgs/nodeinfo.sh

@@ -0,0 +1,8 @@
+sleep 5
+OUTFILE=/var/lib/nodeinfo.nix
+rm -f $OUTFILE
+{
+    echo \{
+    echo "  bitcoind_onion = \"$(cat /var/lib/tor/onion/bitcoind/hostname)\";"
+    echo \}
+} > $OUTFILE