Merge #189: Update configuration.nix

f280d54bb8 add module assertions (nixbitcoin)
23cd323ad1 assertions: add lnd, clightning exclusivity (nixbitcoin)
0ad524ca2d example config: clarify nix-bitcoin will auto-detect invalid settings (nixbitcoin)
c16924b850 example config: change hwi excluding dependency to high-memory (nixbitcoin)
0fd99c4cc0 bitcoind: simplify pruning (nixbitcoin)
b9a7a71873 example config: document enabling pruning (nixbitcoin)

Pull request description:

ACKs for top commit:
  jonasnick:
    ACK f280d54bb8

Tree-SHA512: a900dc2b95cdc01b457c65853930cb1c31b5288fab06d665207ffb2bcd1d54d75add73113ccaacd98e882d4e6674eb8393fec1ae0a01688de1b56250d5d3d3d6

examples/configuration.nix

@@ -23,8 +23,11 @@
   ### BITCOIND
   # Bitcoind is enabled by default if nix-bitcoin is enabled
   #
-  # You can override default settings from secure-node.nix as follows
+  # Enable this option to set pruning to a specified MiB value.
-  # services.bitcoind.prune = lib.mkForce 100000;
+  # clightning is compatible with pruning. See
+  # https://github.com/ElementsProject/lightning/#pruning for more information.
+  # LND and electrs are not compatible with pruning.
+  # services.bitcoind.prune = 100000;
   #
   # You can add options that are not defined in modules/bitcoind.nix as follows
   # services.bitcoind.extraConfig = ''
@@ -42,7 +45,7 @@
   ### LND
   # Disable clightning and uncomment the following line in order to enable lnd,
   # a lightning implementation written in Go.
-  # services.lnd.enable = assert (!config.services.clightning.enable); true;
+  # services.lnd.enable = true;
   ## WARNING
   # If you use lnd, you should manually backup your wallet mnemonic
   # seed. This will allow you to recover on-chain funds. You can run the
@@ -55,16 +58,15 @@
   ### SPARK WALLET
   # Enable this module to use spark-wallet, a minimalistic wallet GUI for
   # c-lightning, accessible over the web or through mobile and desktop apps.
-  # Only enable this if clightning is enabled.
+  # Only available if clightning is enabled.
   # services.spark-wallet.enable = true;
 
   ### ELECTRS
   # Enable this module to use electrs, an efficient re-implementation of
-  # Electrum Server in Rust. Only enable this if hardware wallets are
+  # Electrum Server in Rust.
-  # disabled.
   # services.electrs.enable = true;
   # If you have more than 8GB memory, enable this option so electrs will
-  # sync faster.
+  # sync faster. Only available if hardware wallets are disabled.
   # services.electrs.high-memory = true;
 
   ### LIQUIDD
@@ -76,25 +78,25 @@
 
   ### LIGHTNING CHARGE
   # Enable this module to use lightning-charge, a simple drop-in solution for
-  # accepting lightning payments. Only enable this if clightning is enabled.
+  # accepting lightning payments. Only available if clightning is enabled.
   # services.lightning-charge.enable = true;
 
   ### NANOPOS
   # Enable this module to use nanopos, a simple Lightning point-of-sale
-  # system, powered by Lightning Charge. Only enable this if clightning and
+  # system, powered by Lightning Charge. Only available if clightning and
   # lightning-charge are enabled.
   # services.nanopos.enable = true;
 
   ### WEBINDEX
   # Enable this module to use the nix-bitcoin-webindex, a simple website
-  # displaying your node information and link to nanopos store. Only enable
+  # displaying your node information and link to nanopos store. Only available
-  # this if clightning, lightning-charge, and nanopos are enabled.
+  # if clightning, lightning-charge, and nanopos are enabled.
   # services.nix-bitcoin-webindex.enable = true;
 
   ### RECURRING-DONATIONS
   # Enable this module to send recurring donations. This is EXPERIMENTAL; it's
   # not guaranteed that payments are succeeding or that you will notice payment
-  # failure. Only enable this if clightning is enabled.
+  # failure. Only available if clightning is enabled.
   # services.recurring-donations.enable = true;
   # Specify the receivers of the donations. By default donations are every
   # Monday at a randomized time. Check `journalctl -eu recurring-donations` or
@@ -107,7 +109,7 @@
 
   ### Hardware wallets
   # Enable this module to allow using hardware wallets. See https://github.com/bitcoin-core/HWI
-  # for more information. Only enable this if electrs is disabled.
+  # for more information. Only available if electrs.high-memory is disabled.
   # Ledger must be initialized through the official ledger live app and the Bitcoin app must
   # be installed and running on the device.
   # services.hardware-wallets.ledger = true;

modules/bitcoind.nix

@@ -12,7 +12,7 @@ let
 
     ${optionalString cfg.testnet "testnet=1"}
     ${optionalString (cfg.dbCache != null) "dbcache=${toString cfg.dbCache}"}
-    ${optionalString (cfg.prune != null) "prune=${toString cfg.prune}"}
+    "prune=${toString cfg.prune}
     ${optionalString (cfg.sysperms != null) "sysperms=${if cfg.sysperms then "1" else "0"}"}
     ${optionalString (cfg.disablewallet != null) "disablewallet=${if cfg.disablewallet then "1" else "0"}"}
     ${optionalString (cfg.assumevalid != null) "assumevalid=${cfg.assumevalid}"}
@@ -179,12 +179,8 @@ in {
         description = "Override the default database cache size in megabytes.";
       };
       prune = mkOption {
-        type = types.nullOr (types.coercedTo
+        type = types.ints.unsigned;
-          (types.enum [ "disable" "manual" ])
+        default = 0;
-          (x: if x == "disable" then 0 else 1)
-          types.ints.unsigned
-        );
-        default = null;
         example = 10000;
         description = ''
           Reduce storage requirements by enabling pruning (deleting) of old

modules/electrs.nix

@@ -61,6 +61,12 @@ in {
   };
 
   config = mkIf cfg.enable (mkMerge [{
+    assertions = [
+      { assertion = config.services.bitcoind.prune == 0;
+        message = "electrs does not support bitcoind pruning.";
+      }
+    ];
+
     environment.systemPackages = [ pkgs.nix-bitcoin.electrs ];
 
     systemd.tmpfiles.rules = [

modules/hardware-wallets.nix

@@ -33,6 +33,15 @@ in {
 
   config = mkMerge [
     (mkIf (cfg.ledger || cfg.trezor) {
+      assertions = [
+        { assertion = (config.services.bitcoind.disablewallet == null || !config.services.bitcoind.disablewallet);
+          message = ''
+            Hardware-Wallets are not compatible with bitcoind.disablewallet.
+            Note that this option is active when enabling electrs.high-memory.
+          '';
+        }
+      ];
+
       environment.systemPackages = with pkgs; [
         nix-bitcoin.hwi
         # Provides lsusb for debugging

modules/lightning-charge.nix

@@ -24,6 +24,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.clightning.enable;
+        message = "lightning-charge requires clightning.";
+      }
+    ];
+
     users.users.lightning-charge = {
       description = "lightning-charge User";
       group = "lightning-charge";

modules/lnd.nix

@@ -83,6 +83,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.bitcoind.prune == 0;
+        message = "lnd does not support bitcoind pruning.";
+      }
+    ];
+
     environment.systemPackages = [ cfg.package (hiPrio cfg.cli) ];
 
     systemd.tmpfiles.rules = [

modules/modules.nix

@@ -26,6 +26,15 @@
   };
 
   config = {
+    assertions = [
+      # lnd.wantedBy == [] needed for `test/tests.nix` in which both clightning and lnd are enabled
+      { assertion = config.services.lnd.enable -> (!config.services.clightning.enable || config.systemd.services.lnd.wantedBy == []);
+        message = ''
+          LND and clightning can't be run in parallel because they both bind to lightning port 9735.
+        '';
+      }
+    ];
+
     nixpkgs.overlays = [ (self: super: {
       nix-bitcoin = let
         pkgs = import ../pkgs { pkgs = super; };

modules/nanopos.nix

@@ -52,6 +52,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.lightning-charge.enable;
+        message = "nanopos requires lightning-charge.";
+      }
+    ];
+
     environment.systemPackages = [ pkgs.nix-bitcoin.nanopos ];
     systemd.services.nanopos = {
       description = "Run nanopos";

modules/nix-bitcoin-webindex.nix

@@ -47,6 +47,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.nanopos.enable;
+        message = "nix-bitcoin-webindex requires nanopos.";
+      }
+    ];
+
     systemd.tmpfiles.rules = [
       "d /var/www 0755 nginx nginx - -"
     ];

modules/presets/secure-node.nix

@@ -64,7 +64,6 @@ in {
       addnodes = [ "ecoc5q34tmbq54wl.onion" ];
       discover = false;
       addresstype = "bech32";
-      prune = 0;
       dbCache = 1000;
     };
     services.tor.hiddenServices.bitcoind = mkHiddenService { port = cfg.bitcoind.port; };

modules/recurring-donations.nix

@@ -78,6 +78,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.clightning.enable;
+        message = "recurring-donations requires clightning.";
+      }
+    ];
+
     users.users.recurring-donations = {
         description = "recurring-donations User";
         group = "recurring-donations";

modules/spark-wallet.nix

@@ -46,6 +46,12 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = config.services.clightning.enable;
+        message = "spark-wallet requires clightning.";
+      }
+    ];
+
     environment.systemPackages = [ pkgs.nix-bitcoin.spark-wallet ];
     users.users.spark-wallet = {
       description = "spark-wallet User";