implement doorlock daemon

.gitignore

@@ -1,5 +1,6 @@
 
 node_modules/
+target/
 
 .DS_Store
 ._*

README.md

@@ -1,6 +1,6 @@
 # doorlock
 
-Project Structure:
+**Project Structure:**
 ```
 .
 └── embedded    Embedded System & Hardware
@@ -11,30 +11,48 @@ Project Structure:
 Circuit diagrams are drawn with this [Circuit Simulator](http://www.falstad.com/circuit/).<br/>
 Diagrams are saved as `txt` files, you can import them under `File > Import From Text`.
 
-Relay Board:
+**Relay Board:**
 ![](https://github.com/oursky/doorlock/raw/master/embedded/circuit.png)
 
-Embedded System: Raspberry Pi 3
+**Embedded System:** Raspberry Pi 3
 
-Connections:
+**Connections:**
 * Release Button: GPIO0/Ground
 * Release Signal: GPIO1/Ground
 
 ## Embedded System
-**System:** ArchLinux ARM
+
+### Build
+
+**Dependencies:**
+
+* clojure
+* leiningen
+
+**Build:**
+```
+[~/]$ git clone ...
+[~/doorlock/embedded]$ lein uberjar
+
+```
+The standalone JAR is now in `doorlock/embedded/target/doorlock-<version>-standalone.jar`.
+
+### Deploy
+**Embedded OS:** ArchLinux ARM
 
 **Dependencies:**
-* nodejs
-* npm
+* java
 * wiringpi-git (AUR)
 
 **Install as systemd service:**
+1. copy the standalone JAR to `/home/oursky/`
+2. copy `doorlock.service` to `/etc/systemd/system/`
+3. enable and start the service:
 ```
-[oursky ~/]$ git clone ...
-[oursky ~/]$ sudo cp doorlock/embedded/doorlock.service /etc/systemd/system/
 [oursky ~/]$ sudo systemctl enable doorlock
 [oursky ~/]$ sudo systemctl start doorlock
 ```
-**Note: ** If your username is not `oursky`, you need to edit `doorlock.service` accordingly.
+
+**Note:** If your username is not `oursky`, you need to edit `doorlock.service` accordingly.
 
 ## App

embedded/doorlock.service

@@ -3,8 +3,7 @@ Description=Doorlock Controller Daemon
 
 [Service]
 User=oursky
-WorkingDirectory=/home/oursky/doorlock/embedded
-ExecStart=/usr/bin/npm start
+ExecStart=/usr/bin/java -jar /home/oursky/doorlock-1.0.0-SNAPSHOT-standalone.jar
 
 [Install]
 WantedBy=multi-user.target

embedded/project.clj

@@ -0,0 +1,9 @@
+(defproject com.oursky/doorlock "1.0.0-SNAPSHOT"
+  :min-lein-version "2.0.0"
+  :dependencies [[org.clojure/clojure "1.8.0"]
+                 [org.clojure/core.async "0.2.385"]
+                 [com.taoensso/timbre "4.7.0"]
+                 [http-kit "2.2.0"]
+                 ]
+  :aot :all
+  :main com.oursky.doorlock.core)

embedded/src/com/oursky/doorlock/core.clj

@@ -0,0 +1,50 @@
+(ns com.oursky.doorlock.core
+  (:require [taoensso.timbre :as log]
+            [clojure.java.shell :refer [sh]]
+            [clojure.core.async :refer [<! >! >!! alts! go-loop chan timeout]]
+            [org.httpkit.server :refer [run-server]]
+            )
+  (:gen-class))
+
+; unlock triggering channel
+; identify the trigger source by sending {:source <source>}
+(def unlock-chan (chan))
+
+(defn http-handler [req]
+  (>!! unlock-chan {:source :network})
+  {:status 200})
+
+(defn -main [& args]
+  ; setup GPIO via wiringpi CLI interface
+  ; the clj-gpio library does not support internal pull-up
+  (sh "gpio" "mode" "0" "up")
+  (sh "gpio" "mode" "1" "out")
+
+  ; button event listener
+  ; hold down for atleast 200ms to trigger
+  ; will emit event every 25000ms if held down
+  (go-loop []
+           (if (= 1 (read-string (:out (sh "gpio" "read" "0"))))
+             (sh "gpio" "wfi" "0" "falling")
+             (<! (timeout 2500)))
+           (<! (timeout 200))
+           (when (= 0 (read-string (:out (sh "gpio" "read" "0"))))
+             (>! unlock-chan {:source :button}))
+           (recur))
+
+  ; listen on unlock-chan for unlock events
+  ; if a new unlock event is revieved before the 3000ms timeout, the door is kept open.
+  (go-loop [unlock nil]
+           (when unlock
+             (sh "gpio" "write" "1" "1")
+             (loop [[trigger _] [unlock nil]]
+               (when trigger
+                 (log/info (str "Unlock triggered by " (:source trigger)))
+                 (recur (alts! [unlock-chan (timeout 3000)]))))
+             (sh "gpio" "write" "1" "0")
+             (log/info "Door Locked"))
+           (recur (<! unlock-chan)))
+
+  (run-server http-handler {:ip "0.0.0.0" :port 8090})
+
+  (log/info "=== Daemon Started ==="))