如何在Node.js中將圖像發佈到Twitter

Question

當我嘗試將PNG圖像上載到Node中的Twit庫時，出現錯誤。

我想在Node.js中生成一個隨機RGB顏色的Twitter機器人，創建一個這種顏色的圖片，併發布它。在another question的幫助下，我現在知道如何在Node中創建一個PNG畫布，但我不知道如何將它放入Twit庫。使用下面的代碼，我得到一個錯誤：44, message: 'media_ids parameter is invalid.'似乎來自Twitter API。

Twitter官方文件說：

You may either upload the raw binary of the file or its base64-encoded contents.

我不知道該怎麼做這一點。如何讓Twitter API將我的畫布作爲PNG圖像接受？

我的代碼是：

var Twit = require('twit') 
var Canvas = require('canvas'); 
var Image = Canvas.Image; 


var T = new Twit({ 
    consumer_key:   '###' 
    , consumer_secret:  '###' 
    , access_token:   '###' 
    , access_token_secret: '###' 
}) 

//Generate the canvas 
var canvas = new Canvas(800, 800); 
var context = canvas.getContext('2d'); 

function tweet() { 

//Generate a random colour 
var r = Math.floor((Math.random() * 256)); 
var g = Math.floor((Math.random() * 256)); 
var b = Math.floor((Math.random() * 256)); 
var color = "rgb("+r+","+g+","+b+")"; 

    // draw box 
    context.beginPath(); 
    context.moveTo(0, 00); 
    context.lineTo(0, 800); 
    context.lineTo(800, 800); 
    context.lineTo(800, 0); 
    context.closePath(); 
    context.lineWidth = 5; 
    context.fillStyle = color; 
    context.fill(); 

var fs = require('fs') 
    , out = fs.createWriteStream(__dirname + '/text.png') 
    , stream = canvas.pngStream(); 
var dataUrl = canvas.pngStream().pipe(out); 
//I'm not sure if this bit is really necessary 

    // first we must post the media to Twitter 
T.post('media/upload', { media_data: canvas.toBuffer() }, function (err, data, response) { 

    // now we can reference the media and post a tweet (media will attach to the tweet) 
    var mediaIdStr = data.media_id_string 
    var params = { status: color, media_ids: [mediaIdStr] } 

    T.post('statuses/update', params, function (err, data, response) { 
    console.log(data) 
    }) 
}) 

} 
    setTimeout(tweet, 30000); 

Answer 1

Twitter的docs說這個關於使用media/upload：media_data: canvas.toBuffer()

要解決這個問題：

Parameters

media - The raw binary file content being uploaded. Cannot be used with media_data .

media_data - The base64-encoded file content being uploaded. Cannot be used with media .

您到media_data參數這裏提供的原始數據上傳圖像base64編碼：

T.post('media/upload', { media_data: canvas.toBuffer().toString('base64') }, function (err, data, response) {