基于MiraiBot的开发（定时推送新闻消息）

Kotlin定时任务

Kotlin的定时任务主要通过Timer().schedule()和TimerTask()来实现

schedule()需要三个参数可执行的方法、开始时间、执行间隔时间(毫秒)，参考源码获取更多Timer().schedule()的信息

fun main(){
    Timer().schedule(
        object: TimerTask(){
            override fun run() {
                println("每1秒钟打印一次，Date()表示立刻开始")
            }
        }, Date(),1000)
}

获取每日新闻图片

这一部分属于简单的API调用操作。分为请求API->解析结果->获取资源链接->下载资源。主要使用的工具类OKhttp4和Alibaba JSON2

//获取新闻图片url
val DAILYNEWSAPI = "https://v2.alapi.cn/api/zaobao"
val APITOKEN = "**************"
val params = mutableMapOf("token" to APITOKEN,"format" to "json")
val headers = Headers.headersOf("Content-Type" , "application/x-www-form-urlencoded")
val result = OkHttpClientUtil.getHttpRespondToString(DAILYNEWSAPI, params, headers)
val imageUrl = JSON.parseObject(result).getJSONObject("data").getString("image")
println(imageUrl)
var imagePath: String
//判断系统适配下载路径
if (System.getProperty("os.name").lowercase().contains("linux")) { imagePath = "/root/file/resources/img/mirai/" }else{ imagePath = "./" }
//下载图片文件到本地
val imageTitle: String = LocalDate.now().toString()
val imageFile: File = OkHttpClientUtil.saveImageFile(imagePath,imageUrl,imageTitle,".png")

OkHttpClientUtil.kt

object OkHttpClientUtil {

    private val client = OkHttpClient()

    fun getHttpRespondToString(url: String,params: MutableMap<String,String>,headers: Headers): String {
        val httpUrl = url.toHttpUrl().newBuilder()
        var responseStr = ""
        if (params != null) {
            for (param in params){
                httpUrl.addQueryParameter(param.key,param.value)
            }
        }
        val request = Request.Builder().url(httpUrl.build()).headers(headers).build();
        try {

            val response = client.newCall(request).execute()
            responseStr =  response.body!!.string()
            if(response.body != null) {
                response.body!!.close();
            }
        }catch (e: IOException){
            return "Get Request Error!"
        }
        return responseStr
    }

    /**
     * 在网络上下载图片到本地，使用的是okhttp
     * @param imageUrl 图片链接
     * @param imageTitle 图片标题
     * @param imageFormat 图片文件后缀
     * @param imagePath 保存地址
     * @return File
     * @throws IOException IO异常
     */

    fun saveImageFile(imagePath: String,imageUrl: String,imageTitle: String,imageFormat: String): File{
        val imageFile = File(imagePath + imageTitle + imageFormat)
        val request = Request.Builder().url(imageUrl).build();
        val fos: FileOutputStream
        try {
            fos = FileOutputStream(imageFile)
            val response: Response = client.newCall(request).execute()
            Objects.requireNonNull(response.body)?.bytes()?.let { fos.write(it) }
            fos.close()
            response.close()
        } catch (e: IOException) {
            e.printStackTrace()
        }
        return  imageFile
    }

}

狼宝应用实际开发

这段代码放在了StartBot.kt中 bot.login()之后 bot.join()之前的位置。

//明早9点
val date = LocalDateTime.parse("${LocalDate.now().plusDays(1)}090000", DateTimeFormatter.ofPattern("yyyy-MM-ddHHmmss"))
        .atZone(ZoneId.systemDefault()).toInstant()
Timer().schedule(
    object: TimerTask(){
        override fun run(): Unit = runBlocking {
            //获取open的群列表
            val groupList = GroupService.getOpenGroups()
            //获取新闻图片url
            val DAILYNEWSAPI = "https://v2.alapi.cn/api/zaobao"
            val APITOKEN = "vpu5ehavLNShzQ5a"
            val params = mutableMapOf("token" to APITOKEN,"format" to "json")
            val headers = Headers.headersOf("Content-Type" , "application/x-www-form-urlencoded")
            val result = OkHttpClientUtil.getHttpRespondToString(DAILYNEWSAPI, params, headers)
            val imageUrl = JSON.parseObject(result).getJSONObject("data").getString("image")
            println(imageUrl)
            var imagePath: String
            //判断系统适配下载路径
            if (System.getProperty("os.name").lowercase().contains("linux")) { imagePath = "/root/file/resources/img/mirai/" }else{ imagePath = "./" }
            //下载图片文件到本地
            val imageTitle: String = LocalDate.now().toString()
            val imageFile: File = OkHttpClientUtil.saveImageFile(imagePath,imageUrl,imageTitle,".png")
            groupList.forEach { group: Group ->
                println(group.number)
                bot.getGroup(group.number)?.sendImage(imageFile)
            }
        }
    }, Date.from(date),86400000) //开始于明早9点，间隔24小时执行一次