nixos/ethminer: init

- Tested on NixOS

nixos/modules/module-list.nix

@@ -386,6 +386,7 @@
   ./services/misc/emby.nix
   ./services/misc/errbot.nix
   ./services/misc/etcd.nix
+  ./services/misc/ethminer.nix
   ./services/misc/exhibitor.nix
   ./services/misc/felix.nix
   ./services/misc/folding-at-home.nix

nixos/modules/services/misc/ethminer.nix

@@ -0,0 +1,115 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.ethminer;
+  poolUrl = escapeShellArg "stratum1+tcp://${cfg.wallet}@${cfg.pool}:${toString cfg.stratumPort}/${cfg.rig}/${cfg.registerMail}";
+in
+
+{
+
+  ###### interface
+
+  options = {
+
+    services.ethminer = {
+
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = "Enable ethminer ether mining.";
+      };
+
+      recheckInterval = mkOption {
+        type = types.int;
+        default = 2000;
+        description = "Interval in milliseconds between farm rechecks.";
+      };
+
+      toolkit = mkOption {
+        type = types.enum [ "cuda" "opencl" ];
+        default = "cuda";
+        description = "Cuda or opencl toolkit.";
+      };
+
+      apiPort = mkOption {
+        type = types.int;
+        default = -3333;
+        description = "Ethminer api port. minus sign puts api in read-only mode.";
+      };
+
+      wallet = mkOption {
+        type = types.str;
+        example = "0x0123456789abcdef0123456789abcdef01234567";
+        description = "Ethereum wallet address.";
+      };
+
+      pool = mkOption {
+        type = types.str;
+        example = "eth-us-east1.nanopool.org";
+        description = "Mining pool address.";
+      };
+
+      stratumPort = mkOption {
+        type = types.port;
+        default = 9999;
+        description = "Stratum protocol tcp port.";
+      };
+
+      rig = mkOption {
+        type = types.str;
+        default = "mining-rig-name";
+        description = "Mining rig name.";
+      };
+
+      registerMail = mkOption {
+        type = types.str;
+        example = "email%40example.org";
+        description = "Url encoded email address to register with pool.";
+      };
+
+      maxPower = mkOption {
+        type = types.int;
+        default = 115;
+        description = "Miner max watt usage.";
+      };
+
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf cfg.enable {
+
+    systemd.services.ethminer = {
+      path = [ pkgs.cudatoolkit ];
+      description = "ethminer ethereum mining service";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network.target" ];
+
+      serviceConfig = {
+        DynamicUser = true;
+        ExecStartPost = optional (cfg.toolkit == "cuda") "+${getBin config.boot.kernelPackages.nvidia_x11}/bin/nvidia-smi -pl ${toString cfg.maxPower}";
+      };
+
+      environment = {
+        LD_LIBRARY_PATH = "${config.boot.kernelPackages.nvidia_x11}/lib";
+      };
+
+      script = ''
+        ${pkgs.ethminer}/bin/.ethminer-wrapped \
+          --farm-recheck ${toString cfg.recheckInterval} \
+          --report-hashrate \
+          --${cfg.toolkit} \
+          --api-port ${toString cfg.apiPort} \
+          --pool ${poolUrl}
+      '';
+
+    };
+
+  };
+
+}