1、使用rrdtool建立rrd文件,对人民币对美元汇率每20秒进行一次抓取(setp = 20s)
rrdtool create USDCNY.rrd \
--start `date +%s` \
--step 20 \
DS:content:GAUGE:100:0:U \
RRA:AVERAGE:0:1:400
2、 通过Yahoo提供的汇率查询解决取得当前汇率,并存入rrd文件
#!/bin/bash
PATH='/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin'
rrdfile='/tmp/361way/USDCNY.rrd'
while true
do
timestamp=`date +%s`
rmbrate=`curl 'http://download.finance.yahoo.com/d/quotes.csv?s=USDCNY=X&f=sl1d1t1&e=.csv' 2>/dev/null | awk -F, '{print $2}'`
rrdtool update $rrdfile ${timestamp}:${rmbrate}
sleep 19
echo 'get now'
done
3、使用php脚本展示人民币汇率rrd图
# cat rmb.php
<?php
header("Content-type:image/png");
$cmd='
/usr/bin/rrdtool graph - \
-h 120 -w 500 \
--start now-1h \
-v "RMB/USD" --title "RMB-USD Rate" \
DEF:rmbrate=/tmp/361way/USDCNY.rrd:content:AVERAGE \
LINE:rmbrate#00CF00FF:"RMB Rate" \
COMMENT:"\n"
';
passthru($cmd);
?>
效果图如下: