======温度・湿度センサー======

参考
  * https://www.infiniteloop.co.jp/blog/2013/02/raspberrypitem/
  * http://blog.bnikka.com/raspberrypi/am2302dht22raspberrypi.html
  * http://tomo.blue/others/raspberrypi/%E6%B8%A9%E5%BA%A6%E3%83%BB%E6%B9%BF%E5%BA%A6%E3%81%AE%E3%83%87%E3%83%BC%E3%82%BF%E3%82%92%E5%8F%96%E5%BE%97%E3%81%99%E3%82%8B%E6%96%B9%E6%B3%95/

GPIO端子
  * 黄 (+) P1(1:3V)
  * 緑 (Out) P123(4:GPIO4)
  * 青 (-)  P1の上の段  24(6:gnd)

pythonインストール
<code>
$ sudo apt-get update
$ apt-get upgrade
# apt-get upgradeすると、kernelがかきかわるので、fsprotectが無効になるはず・・・
(http://www.sabo-net.info/2015/06/09/raspberry-pi%E3%82%92readonly%E3%81%AB%E3%81%97%E3%81%A6%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB%E3%82%B7%E3%82%B9%E3%83%86%E3%83%A0%E4%BF%9D%E8%AD%B7%EF%BC%81/)
</code>

Adafruit_Python_DHTのソースコードを取得
<code>
$ sudo apt-get install build-essential python-dev
$ sudo git clone https://github.com/adafruit/Adafruit_Python_DHT.git
$ cd Adafruit_Python_DHT
$ sudo python setup.py install
</code>

動作確認
<code>
$ cd examples
$ sudo ./AdafruitDHT.py 22 4 
Temp=19.0*C  Humidity=46.0%
</code>

スクリプト作成(temperature)
<code>
$ cp AdafruitDHT.py temp.py
$ vi temp.py

if humidity is not None and temperature is not None:
    print '{}'.format(temperature) 
    (ここを編集)

    - - - - 拡張 - - - -
    f=open('/var/log/temp.log', 'w')
    f.write('{:.1f}'.format(temperature))
    f.close()
    - - - -
</code>

スクリプト作成(humidity)
<code>
$ cp AdafruitDHT.py humid.py
$ vi humid.py
if humidity is not None and temperature is not None:
    print '{}'.format(humidity)  #!!!!!!!←ここを左記のように編集!!!!!!!!
    (ここを編集)

$ sudo cp temp.py /usr/local/bin
$ sudo cp humid.py /usr/local/bin
</code>

apache導入
<code>
$ sudo apt-get install apache2
</code>

Mumin導入
<code>
$ sudo apt-get install munin munin-node
</code>

Munin用スクリプト準備(temperature)

$ sudo vi /usr/share/munin/plugins/temp

<code>
#!/bin/sh
#%# family=auto
#%# capabilities=autoconf
GETNUM=`python /usr/local/bin/temp.py 22 4`
if [ "$1" = "autoconf" ]; then
        if [ -n ${GETNUM} ] ; then
                echo yes
                exit 0
        else
                echo no
                exit 0
        fi
fi
if [ "$1" = "config" ]; then
        echo 'graph_title temperature'
        echo 'graph_args -r --lower-limit 0'
        echo 'graph_vlabel C'
        echo 'graph_category Weather'
        echo 'total.label temperature'
        echo 'total.min 0'
        echo 'total.draw LINE2'
        echo 'total.type GAUGE'
        exit 0
fi
echo "total.value $GETNUM";
</code>

Munin用スクリプト準備(humidity)

$ sudo vi /usr/share/munin/plugins/humid

<code>
#!/bin/sh
#%# family=auto
#%# capabilities=autoconf
GETNUM=`python /usr/local/bin/humid.py 22 4`
if [ "$1" = "autoconf" ]; then
        if [ -n ${GETNUM} ] ; then
                echo yes
                exit 0
        else
                echo no
                exit 0
        fi
fi
if [ "$1" = "config" ]; then
        echo 'graph_title humidity'
        echo 'graph_args -r --lower-limit 0'
        echo 'graph_vlabel %'
        echo 'graph_category Weather'
        echo 'total.label humidity'
        echo 'total.min 0'
        echo 'total.draw LINE2'
        echo 'total.type GAUGE'
        exit 0
fi
echo "total.value $GETNUM";
</code>

munin用スクリプトの実行権限等を設定
<code>
$ chmod 755 /usr/share/munin/plugins/temp
$ chmod 755 /usr/share/munin/plugins/humid
$ sudo ln -s /usr/share/munin/plugins/temp /etc/munin/plugins/temp
$ sudo ln -s /usr/share/munin/plugins/humid /etc/munin/plugins/humid
</code>

munin pluginフォルダの設定
<code>
$ sudo chmod 755 /etc/munin/plugin-conf.d/
</code>


$ sudo vi /etc/munin/plugin-conf.d/temp
<code>
[temp]
user root
</code>

$ sudo vi /etc/munin/plugin-conf.d/humid
<code>
[humid]
user root
</code>

# vi /etc/munin/munin.conf
<code>
dbdir   /var/munin/lib
htmldir /var/munin/www
</code>

munin実行フォルダの設定
<code>
# mkdir /var/munin
# mv /var/lib/munin /var/munin/lib
# mv /var/cache/munin/www /var/munin/www
# cd /var/www/html/
# ln -s /var/munin/www ./munin
</code>

# vi /etc/apache2/conf-enabled/munin.conf
<code>
Alias /munin "/var/munin/www"
<Directory "/var/munin/www">
        #Require local
        Require all granted
        Options None
</Directory>
</code>

# vi /etc/apache2/conf-enabled/munin.conf
<code>
<Location /munin-cgi/munin-cgi-graph>
        #Require local
        Require all granted
…
</Location>
</code>


munin のリスタート
<code>
# /etc/init.d/munin stop
# /etc/init.d/munin-node stop
</code>

www/libをUSBメモリに作成する場合
<code>
# sudo chown -R munin.munin /var/munin/lib
# sudo chown -R munin.munin /var/munin/www
# chown -h munin.munin …. シンボリックリンクの場合は-hオプションを指定
# /etc/init.d/munin-node restart
# apache2ctl restart
</code>

USBメモリの準備
<code>
# fdisk /dev/sda
    Command (m for help): n
    Command (m for help): w
# mkfs.ext4 /dev/sda1
# fdisk -l
# blkid /dev/sda1
/dev/sda1: UUID="64ec5b43-30cf-4082-8129-78ee1c6a633d" TYPE="ext4" PARTUUID="64670bc5-b82f-43c6-82e3-d2577c356f60"
# mkdir /mnt/usb01
# vi /etc/fstab
UUID="c21e1887-bf12-4a2c-9303-abd2dd7c0127" /mnt/usb01 ext4      defaults        0       2
# mkdir /mnt/usb01
# mount -a
# cp -r /var/munin /mnt/usb01
# chown -R munin.munin /mnt/usb01/munin
# mv /var/munin /var/munin.org; ln -s /mnt/usb01/munin /var/munin

(障害の際、/var/munin.orgを新usb01にコピーしchown してもよい)
</code>

=====補足=====

黒ケースのIFで使うなら AdafruitDHT.py 22 3 でOK
# sudo ./AdafruitDHT.py 22 3
<code>
[Chasis GND] - 茶 - [Sensor -]
[Chasis 3.3V ] - 赤 - [Sensor out]
[Chasis SCL  ] - 橙 - [Sensor +]
[Chasis SDA ] - 橙 - (open)
</code>