Faraday

examples/configuration.nix

@@ -153,6 +153,11 @@
   # Automatically enables lnd.
   # services.lightning-loop.enable = true;
 
+  ### faraday
+  # Enable this module to use lightninglab's Channel Management & Optimization Tool.
+  # faraday (faraday daemon) will be started automatically. Users can
+  # interact with the daemon using `frcli`.
+  # services.faraday.enable = true;
   ### Backups
   # Enable this module to use nix-bitcoin's own backups module. By default, it
   # uses duplicity to incrementally back up all important files in /var/lib to

modules/faraday.nix

@@ -0,0 +1,90 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.faraday;
+  inherit (config) nix-bitcoin-services;
+  secretsDir = config.nix-bitcoin.secretsDir;
+  network = config.services.bitcoind.network;
+  rpclisten = "${cfg.rpcAddress}:${toString cfg.rpcPort}";
+in {
+
+  options.services.faraday = {
+    enable = mkEnableOption "faraday";
+    package = mkOption {
+      type = types.package;
+      default = config.nix-bitcoin.pkgs.faraday;
+      defaultText = "pkgs.nix-bitcoin.faraday";
+      description = "The package providing faraday binaries.";
+    };
+    rpcAddress = mkOption {
+       type = types.str;
+       default = "localhost";
+       description = "Address to listen for gRPC connections.";
+    };
+    rpcPort = mkOption {
+       type = types.port;
+       default = 8465;
+       description = "Port to listen for gRPC connections.";
+    };
+    faradayDir = mkOption {
+      type = types.path;
+      default = "/var/lib/faraday";
+      description = "The data directory for faraday.";
+    };
+    extraArgs = mkOption {
+      type = types.separatedString " ";
+      default = "";
+      description = "Extra command line arguments passed to faraday.";
+    };
+    cli = mkOption {
+      default = pkgs.writeScriptBin "frcli"
+      ''
+        ${cfg.package}/bin/frcli \
+        --rpcserver ${rpclisten} \
+        --faradaydir ${cfg.faradayDir} "$@"
+      '';
+      description = "Binary to connect with the faraday instance.";
+    };
+    enforceTor =  nix-bitcoin-services.enforceTor;
+  };
+
+  config = mkIf cfg.enable {
+    services.lnd.enable = true;
+
+    environment.systemPackages = [ cfg.package (hiPrio cfg.cli) ];
+
+    systemd.tmpfiles.rules = [
+      "d '${cfg.faradayDir}' 0770 lnd lnd - -"
+    ];
+
+
+    systemd.services.faraday = {
+      description = "Run faraday";
+      wantedBy = [ "multi-user.target" ];
+      requires = [ "lnd.service" ];
+      after = [ "lnd.service" ];
+      serviceConfig = nix-bitcoin-services.defaultHardening // {
+        preStart = ''
+        mkdir -p ${cfg.faradayDir}
+        chown -R 'lnd:lnd' '${cfg.faradayDir}'
+        '';
+        ExecStart = ''
+          ${cfg.package}/bin/faraday \
+          --faradaydir=${cfg.faradayDir} \
+          --rpclisten=${rpclisten} \
+          --lnd.rpcserver=${config.services.lnd.rpcAddress}:${toString config.services.lnd.rpcPort} \
+          --lnd.macaroondir=${config.services.lnd.networkDir} \
+          --lnd.tlscertpath=${secretsDir}/lnd-cert 
+        '';
+        User = "lnd";
+        Restart = "on-failure";
+        RestartSec = "10s";
+        ReadWritePaths = "${cfg.faradayDir}";
+      } // (if cfg.enforceTor
+          then nix-bitcoin-services.allowTor
+          else nix-bitcoin-services.allowAnyIP);
+    };
+  };
+}

modules/modules.nix

@@ -14,6 +14,7 @@ with lib;
     ./spark-wallet.nix
     ./lnd.nix
     ./lightning-loop.nix
+    ./faraday.nix
     ./btcpayserver.nix
     ./electrs.nix
     ./liquid.nix

modules/netns-isolation.nix

@@ -245,6 +245,10 @@ in {
       joinmarket-ob-watcher = {
         id = 26;
       };
+      faraday = {
+        id = 28;
+        connections = [ "lnd" ];
+      };
     };
 
     services.bitcoind = {

pkgs/default.nix

@@ -10,6 +10,7 @@ let self = {
   nixops19_09 = pkgs.callPackage ./nixops { };
   netns-exec = pkgs.callPackage ./netns-exec { };
   lightning-loop = pkgs.callPackage ./lightning-loop { };
+  faraday = pkgs.callPackage ./faraday { };
   extra-container = pkgs.callPackage ./extra-container { };
   clightning-plugins = import ./clightning-plugins pkgs self.nbPython3Packages;
   clboss = pkgs.callPackage ./clboss { };

pkgs/faraday/default.nix

@@ -0,0 +1,22 @@
+{ pkgs, buildGoModule, fetchurl, lib }:
+
+buildGoModule rec {
+  pname = "faraday";
+  version = "0.2.3-alpha";
+
+  src = fetchurl {
+    url = "https://github.com/lightninglabs/faraday/archive/v${version}.tar.gz";
+    # Use ./get-sha256.sh to fetch latest (verified) sha256
+    sha256 = "c016e2b16160f24abdfce0f71cdb848da3e3d78cff450fb353017d4104bd616e";
+  };
+
+  subPackages = [ "cmd/faraday" "cmd/frcli" ];
+
+  vendorSha256 = "1hh99nfprlmhkc36arg3w1kxby59i2l7n258cp40niv7bjn37hrq";
+
+  meta = with lib; {
+    description = " Faraday: Lightning Channel Management & Optimization Tool";
+    homepage = "https://github.com/lightninglabs/faraday";
+    license = lib.licenses.mit;
+  };
+}

pkgs/faraday/get-sha256.sh

@@ -0,0 +1,26 @@
+#! /usr/bin/env nix-shell
+#! nix-shell -i bash -p git gnupg
+set -euo pipefail
+
+TMPDIR="$(mktemp -d -p /tmp)"
+trap "rm -rf $TMPDIR" EXIT
+cd $TMPDIR
+
+echo "Fetching latest release"
+git clone https://github.com/lightninglabs/faraday 2> /dev/null
+cd faraday
+latest=$(git describe --tags `git rev-list --tags --max-count=1`)
+echo "Latest release is ${latest}"
+
+
+# GPG verification
+export GNUPGHOME=$TMPDIR
+echo "Fetching Calra Kirk Cohen's Key"
+gpg --keyserver hkps://keyserver.ubuntu.com --recv-keys 15E7ECF257098A4EF91655EB4CA7FE54A6213C91 2> /dev/null
+
+echo "Verifying latest release"
+git verify-tag ${latest}
+
+echo "tag: ${latest}"
+# The prefix option is necessary because GitHub prefixes the archive contents in this format
+echo "sha256: $(git archive --format tar.gz --prefix=faraday-${latest//v}/ ${latest} | sha256sum | cut -d\  -f1)"

pkgs/pinned.nix

@@ -13,6 +13,10 @@ in
     lnd
     nbxplorer
     btcpayserver;
+  inherit (nixBitcoinPkgsUnstable)
+    electrs
+    lightning-loop
+    faraday;
 
   stable = nixBitcoinPkgsStable;
   unstable = nixBitcoinPkgsUnstable;

test/tests.nix

@@ -48,6 +48,8 @@ let testEnv = rec {
 
       tests.lightning-loop = cfg.lightning-loop.enable;
 
+      tests.faraday = cfg.faraday.enable;
+
       tests.electrs = cfg.electrs.enable;
 
       tests.liquidd = cfg.liquidd.enable;
@@ -116,6 +118,7 @@ let testEnv = rec {
       services.spark-wallet.enable = true;
       services.lnd.enable = true;
       services.lightning-loop.enable = true;
+      services.faraday.enable = true;
       services.electrs.enable = true;
       services.liquidd.enable = true;
       services.btcpayserver.enable = true;

test/tests.py

@@ -176,6 +176,15 @@ def _():
     )
 
 
+@test("faraday")
+def _():
+    assert_running("faraday")
+    assert_matches("su operator -c 'frcli --version'", "version")
+    # Check that lightning-loop fails with the right error, making sure
+    # lightning-loop can connect to lnd
+    machine.wait_until_succeeds(log_has_string("faraday", "gRPC",))
+
+
 @test("btcpayserver")
 def _():
     assert_running("nbxplorer")