restucture and add redis

services/redis.nix

@@ -0,0 +1,73 @@
+{
+  pkgs,
+}:
+let
+  inherit (pkgs) lib;
+in
+{
+  name,
+  default_config ? true,
+  extra_config ? '''',
+  package ? pkgs.redis,
+  port ? 5432,
+  bind ? "localhost",
+  ...
+}:
+
+let
+
+  generateRedisConfig = ''
+    cat > $RUNTIME_PATH/${name}.conf <<EOF
+    ${lib.optionalString default_config ''
+      port ${port}
+      ${lib.optionalString (bind != null) "bind ${bind}"}
+      ${lib.optionalString (port == 0) "unixsocket $RUNTIME_PATH/${name}.sock"}
+      ${lib.optionalString (port == 0) "unixsocketperm 700"}
+    ''}
+    ${extra_config}
+    EOF
+  '';
+
+  script = pkgs.writeShellApplication {
+    name = "run-redis";
+    text = ''
+      set -euo pipefail
+      REDISDATA=$RUNTIME_PATH/${name}/
+      ${
+        if (port == 0) then
+          ''
+            REDIS_UNIX_SOCKET = $RUNTIME_PATH/${name}.sock
+            export REDIS_UNIX_SOCKET
+            echo "Starting redis on unix socket ''${REDIS_UNIX_SOCKET}"
+          ''
+        else
+          ''
+            echo "Starting redis on port ${port}"
+          ''
+      }
+      export REDISDATA
+      if [ ! -d $REDISDATA ]; then
+        mkdir -p $REDISDATA
+      fi
+      ${generateRedisConfig}
+      ${package}/bin/redis-server $RUNTIME_PATH/${name}.conf --daemonize no --dir "$REDISDATA"
+    '';
+  };
+  tcpPing = "${package}/bin/redis-cli -p ${builtins.toString port} ping";
+  unixPing = "${package}/bin/redis-cli -s $RUNTIME_PATH/${name}.sock ping";
+in
+{
+  processes."${name}" = {
+    command = "${script}/bin/run-redis";
+    readiness_probe = {
+      exec.command = if port == 0 then unixPing else tcpPing;
+      initial_delay_seconds = 2;
+      period_seconds = 10;
+      timeout_seconds = 4;
+      success_threshold = 1;
+      failure_threshold = 3;
+    };
+    availability.restart = "on_failure";
+  };
+
+}