From 08f8d721fa2d51595cdfafff26b6e9a663fb57a0 Mon Sep 17 00:00:00 2001
From: niten <niten@fudo.org>
Date: Mon, 24 Apr 2023 09:49:57 -0700
Subject: [PATCH] Add module.nix

---
 flake.nix            |  2 +-
 module.nix           | 71 ++++++++++++++++++++++++++++++++++++++++++++
 src/snooper/cli.clj  | 17 ++++++++---
 src/snooper/core.clj | 21 ++++++++-----
 4 files changed, 98 insertions(+), 13 deletions(-)
 create mode 100644 module.nix

diff --git a/flake.nix b/flake.nix
index 9f9d591..9bc1d90 100644
--- a/flake.nix
+++ b/flake.nix
@@ -17,7 +17,7 @@
         packages = rec {
           default = snooper-server;
           snooper-server = helpers.packages."${system}".mkClojureBin {
-            name = "org.fudo/snooper";
+            name = "org.fudo/snooper-server";
             primaryNamespace = "snooper.cli";
             src = ./.;
           };
diff --git a/module.nix b/module.nix
new file mode 100644
index 0000000..190bcdd
--- /dev/null
+++ b/module.nix
@@ -0,0 +1,71 @@
+packages:
+
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+  snooper-server = packages."${pkgs.system}.snooper-server";
+  cfg = config.services.snooper;
+
+in {
+  options.services.snooper = with types; {
+    enable = mkEnableOption "Enable Snooper notifiaction server.";
+
+    verbose = mkEnableOption "Generate verbose logs and output.";
+
+    event-topics = mkOption {
+      type = listOf str;
+      description = "MQTT topics on which to listen for detection events.";
+    };
+
+    notification-topic = mkOption {
+      type = str;
+      description = "MQTT topic on which to send notifications.";
+    };
+
+    mqtt-client = {
+      host = mkOption {
+        type = str;
+        description = "Hostname of the MQTT server.";
+      };
+
+      port = mkOption {
+        type = port;
+        description = "Port on which the MQTT server is listening.";
+        default = 1883;
+      };
+
+      username = mkOption {
+        type = str;
+        description = "User as which to connect to the MQTT server.";
+      };
+
+      password-file = mkOption {
+        type = str;
+        description =
+          "File (on the local host) containing the password for the MQTT server.";
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.snooper = {
+      path = [ snooper-server ];
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        DynamicUser = true;
+        LoadCredential = [ "mqtt.passwd:${cfg.mqtt-client.password-file}" ];
+        ExecStart = pkgs.writeShellScript "snooper-server.sh"
+          (concatStringsSep " " ([
+            "snooper-server"
+            "--mqtt-host=${cfg.mqtt.host}"
+            "--mqtt-port=${toString cfg.mqtt.port}"
+            "--mqtt-user=${cfg.mqtt.username}"
+            "--mqtt-password-file=$CREDENTIALS_DIRECTORY/mqtt.passwd"
+            "--notification-topic=${cfg.notification-topic}"
+          ] ++ (map (topic: "--event-topic=${topic}") cfg.event-topics)
+            ++ (optional cfg.verbose "--verbose")));
+      };
+    };
+  };
+}
diff --git a/src/snooper/cli.clj b/src/snooper/cli.clj
index c5fb158..1086323 100644
--- a/src/snooper/cli.clj
+++ b/src/snooper/cli.clj
@@ -5,10 +5,12 @@
             [clojure.string :as str]
             [snooper.core :as snooper]
             [milquetoast.client :as mqtt]
-            [fudo-clojure.logging :as log]))
+            [fudo-clojure.logging :as log])
+  (:gen-class))
 
 (def cli-opts
   [["-v" "--verbose" "Provide verbose output."]
+   ["-h" "--help" "Print this message."]
 
    [nil "--mqtt-host HOSTNAME" "Hostname of MQTT server."]
    [nil "--mqtt-port PORT" "Port on which to connect to the MQTT server."
@@ -44,13 +46,15 @@
 (defn -main [& args]
   (let [required-args #{:mqtt-host :mqtt-port :mqtt-user :mqtt-password-file :event-topic :notification-topic}
         {:keys [options _ errors summary]} (parse-opts args required-args cli-opts)]
+    (when (:help options) (msg-quit 0 (usage summary)))
     (when (seq errors) (msg-quit 1 (usage summary errors)))
     (let [{:keys [mqtt-host
                   mqtt-port
                   mqtt-user
                   mqtt-password-file
                   notification-topic
-                  event-topic]} options
+                  event-topic
+                  verbose]} options
           catch-shutdown (async/chan)
           mqtt-client (mqtt/connect-json! :host mqtt-host
                                           :port mqtt-port
@@ -59,13 +63,18 @@
                                                         (slurp)
                                                         (str/trim)))
           logger (log/print-logger)]
-      (snooper/listen! :mqtt-client mqtt-client
+      (when verbose
+        (println (format "launching snooper server to listen on %s and report events on %s"
+                         event-topic notification-topic)))
+      (snooper/listen! :mqtt-client        mqtt-client
                        :notification-topic notification-topic
                        :event-topics       event-topic
-                       :logger             logger)
+                       :logger             logger
+                       :verbose            verbose)
       (.addShutdownHook (Runtime/getRuntime)
                         (Thread. (fn [] (>!! catch-shutdown true))))
       (<!! catch-shutdown)
+      (println "stopping snooper server")
       ;; Stopping the MQTT will stop tattler
       (mqtt/stop! mqtt-client)
       (System/exit 0))))
diff --git a/src/snooper/core.clj b/src/snooper/core.clj
index ee82a82..2778983 100644
--- a/src/snooper/core.clj
+++ b/src/snooper/core.clj
@@ -1,18 +1,21 @@
 (ns snooper.core
-  (:require [clojure.core.async :refer [go-loop alts! chan]]
+  (:require [clojure.core.async :refer [go-loop alts!]]
+            [clojure.pprint :refer [pprint]]
             [fudo-clojure.logging :as log]
             [milquetoast.client :as mqtt]
             [malli.core :as t]))
 
-(defn pthru [o] (clojure.pprint/pprint o) o)
-
 (def critical-objects [:person :bear])
 (def normal-objects [:cat :dog])
 
+(defn- verbose-pthru [verbose obj]
+  (when verbose (pprint obj))
+  obj)
+
 (defn- objects-criticality [objs]
   (cond (some (partial contains? objs) critical-objects) :high
         (some (partial contains? objs) normal-objects)   :medium
-        :else                                            nil))
+        :else                                            :low))
 
 (defn- objects-probability [objs]
   (let [prob (apply max (vals objs))]
@@ -58,7 +61,7 @@
 (defmethod event-summary :possibly [{:keys [description location]}]
   (format "There could possibly be %s at the %s" description location))
 (defmethod event-summary :likely [{:keys [description location]}]
-  (format "There's might %s at the %s" description location))
+  (format "There might be %s at the %s" description location))
 (defmethod event-summary :probably [{:keys [description location]}]
   (format "There's probably %s at the %s" description location))
 (defmethod event-summary :definitely [{:keys [description location]}]
@@ -84,17 +87,19 @@
   [& {mqtt-client        :mqtt-client
       notification-topic :notification-topic
       event-topics       :event-topics
-      logger             :logger}]
+      logger             :logger
+      verbose            :verbose}]
   (let [incoming (map (partial mqtt/subscribe! mqtt-client) event-topics)
         valid-evt? (t/validator MotionEvent)]
     (go-loop [evts (alts! incoming)]
       (let [evt (first evts)]
-        (clojure.pprint/pprint evt)
+        (when verbose (pprint evt))
         (cond (nil? evt)       (log/info! logger "stopping")
               (valid-evt? evt) (do (log/info! logger (format "received motion event id %s from %s"
                                                              (:id evt)
                                                              (:topic evt)))
-                                   (mqtt/send! mqtt-client notification-topic (pthru (translate-event (:payload evt))))
+                                   (mqtt/send! mqtt-client notification-topic
+                                               (verbose-pthru verbose (translate-event (:payload evt))))
                                    (recur (alts! incoming)))
               :else            (do (log/error! logger (format "invalid motion event: %s" evt))
                                    (recur (alts! incoming))))))))