espruino/esp8266 加载远程代码

今天玩esp8266的时候突然想到, 是不是可以直接运行线上代码, 这样的话就可以灵活的配置esp8266执行什么操作了, 也不用每次更新代码都要把设备拆下来搞到电脑上去下载程序, 因为本身esp8266就需要联网工作, 所以就想到了联网后获取在线代码进行执行, 如果代码更新只需要重启设备就可以了, 不用每次都插到电脑上去下载代码. 后来翻了一下espruino的文档发现有提供加载线上模块的方法, 于是就实现了一下, 下面是加载远程代码的逻辑.

烧录espruino固件并下载代码

1. 配置wifi和线上代码地址 (注意需要使用http协议, 不支持https协议)
2. 将代码写入esp8266
3. 编写线上代码
4. 重启设备
5. 重启后设备就会自动联网和拉取指定的代码并执行了.

var wifi = require('Wifi');
var app = {
    config: {
        wifi: {
            ssid: '你的wifi名称',
            password: '你的wifi密码'
        },
        // 你的线上代码地址
        online: 'http://espjs.admin-ui.cn/ota.js'
    },
    init: function () {
        this.wifi();
    },
    wifi: function () {
        var self = this;
        console.log('wifi connecting...');
        wifi.connect(self.config.wifi.ssid, { password: self.config.wifi.password }, err => {
            if (err) {
                console.log('wifi connect error: ', err);
                return;
            }
            wifi.getIP(function (err, result) {
                self.onWifiConnected(result);
            });
        });
    },
    run: function () {
        this.init();
    },
    onWifiConnected: function (result) {
        console.log('wifi connected: ', result);
        this.loadModule(this.config.online);
    },
    loadModule: function (url, callback) {
        if (url.substr(0, 4) !== 'http') {
            url = 'http://www.espruino.com/modules/' + url + '.min.js';
        }
        require("http").get(url, function (res) {
            var contents = "";
            res.on('data', function (data) { contents += data; });
            res.on('close', function () {
                Modules.addCached(url, contents);
                if (callback) callback();
            });
        }).on('error', function (e) {
            console.log("ERROR", e);
        });
    }
};
app.run();

案例

比如我这里用了自己的域名, 线上代码是一个获取温湿度和显示的一个例子.
代码地址: http://espjs.admin-ui.cn/ota.js

var demo = {
    config: {
        dht: {
            pin: NodeMCU.D1
        },
        oled: {
            scl: NodeMCU.D5,
            sda: NodeMCU.D4,
            width: 128,
            height : 64
        },
        led: {
            pin: NodeMCU.D2,
        }
    },
    device: {
        dht: null,
        oled: null,
        led: null
    },
    init: function () {
        this.led();
        this.oled();
        this.dht(2000);
    },
    led: function () {
        var self = this;
        app.loadModule('http://espjs.admin-ui.cn/libs/led.js', function (LED) {
            self.device.led = new LED(self.config.led.pin);
            self.device.led.close();
        });
    },
    dht: function (time) {
        var self = this;
        app.loadModule('DHT11', function (dht11) {
            self.device.dht = dht11.connect(self.config.dht.pin);
            setInterval(function () {
                self.device.dht.read(function (result) {
                    self.onDht(result.temp, result.rh);
                });
            }, time);
        });
    },
    oled: function () {
        var self = this;
        var i2c = new I2C();
        i2c.setup({
            scl: this.config.oled.scl,
            sda: this.config.oled.sda,
            bitrate: 100000
        });
        var config = {
            width: this.config.oled.width,
            height: this.config.oled.height
        };
        app.loadModule('SH1106', function (ssd1306) {
            self.device.oled = ssd1306.connect(i2c, function () {
                self.onOledInit();
            }, config);
        })
    },
    run: function () {
        this.init();
    },
    onDht: function (temp, rh) {
        console.log('Temp is ' + temp + ' and RH is ' + rh);
        if (this.device.oled) {
            this.device.oled.clear(true);
            this.device.oled.drawString('Temp: ' + temp , 40 , 20);
            this.device.oled.drawString('RH: ' + rh, 40 , 40);
            this.device.oled.flip();
        }
    },
    onWifiConnected: function (result) {
        console.log('wifi connected: ', result);
    },
    onOledInit: function () {
        this.device.oled.clear(true);
        this.device.oled.drawString("Hello World!", 50 , 40);
        this.device.oled.flip();
        console.log('oled init finish');
    }
};
demo.run();

效果是这样的: