SVG到PNG服务器端-使用node.js



我正试图按照本教程将d3.js SVG Vis转换为PNG服务器端(使用Node.js)http://eng.wealthfront.com/2011/12/converting-dynamic-svg-to-png-with.html

完整代码链接:https://gist.github.com/1509145

然而,每当我试图请求加载我的页面时,我总是会收到这个错误

    /Users/me/Node/node_modules/jsdom/lib/jsdom.js:171
        features   = JSON.parse(JSON.stringify(window.document.implementation._fea
                                                              ^
    TypeError: Cannot read property 'implementation' of undefined
        at exports.env.exports.jsdom.env.processHTML (/Users/dereklo/Node/node_modules/jsdom/lib/jsdom.js:171:59)
        at Object.exports.env.exports.jsdom.env (/Users/dereklo/Node/node_modules/jsdom/lib/jsdom.js:262:5)
        at Server.<anonymous> (/Users/dereklo/Node/Pie/pie_serv.js:26:9)
        at Server.EventEmitter.emit (events.js:91:17)
        at HTTPParser.parser.onIncoming (http.js:1785:12)
        at HTTPParser.parserOnHeadersComplete [as onHeadersComplete] (http.js:111:23)
        at Socket.socket.ondata (http.

有人知道为什么会这样吗?我已经很好地安装了jsdom模块,所以我真的不知道是什么导致了这些问题。。。提前谢谢。

编辑

这是我用来实现node.js服务器的代码。我的最新一期在这个来源下面。。。

var http = require('http'),
    url = require('url'),
    jsdom = require('jsdom'),
    child_proc = require('child_process'),
    w = 400,
    h = 400,
    __dirname = "Users/dereklo/Node/pie/"
   scripts = ["/Users/dereklo/Node/pie/d3.min.js",
               "/Users/dereklo/Node/pie/d3.layout.min.js",
               "/Users/dereklo/Node/pie/pie.js"],
      //scripts = ["./d3.v2.js",
        //         "./d3.layout.min.js",
          //       "./pie.js"]
    htmlStub = '<!DOCTYPE html><div id="pie" style="width:'+w+'px;height:'+h+'px;"></div>';
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'image/png'});
  var convert = child_proc.spawn("convert", ["svg:", "png:-"]),
      values = (url.parse(req.url, true).query['values'] || ".5,.5")
        .split(",")
        .map(function(v){return parseFloat(v)});
  convert.stdout.on('data', function (data) {
    res.write(data);
  });
  convert.on('exit', function(code) {
    res.end();
  });
  jsdom.env({features:{QuerySelector:true}, html:htmlStub, scripts:scripts, done:function(errors, window) {
    var svgsrc = window.insertPie("#pie", w, h, values).innerHTML;
  console.log("svgsrc",svgsrc);
    //jsdom's domToHTML will lowercase element names
    svgsrc = svgsrc.replace(/radialgradient/g,'radialGradient');
    convert.stdin.write(svgsrc);
    convert.stdin.end();
  }});
}).listen(8888, "127.0.0.1");
console.log('Pie SVG server running at http://127.0.0.1:8888/');
console.log('ex. http://127.0.0.1:8888/?values=.4,.3,.2,.1');

最新问题

    events.js:66
        throw arguments[1]; // Unhandled 'error' event
                       ^
Error: This socket is closed.
    at Socket._write (net.js:519:19)
    at Socket.write (net.js:511:15)
    at http.createServer.jsdom.env.done (/Users/dereklo/Node/Pie/pie_serv.js:38:19)
    at exports.env.exports.jsdom.env.scriptComplete (/Users/dereklo/Node/node_modules/jsdom/lib/jsdom.js:199:39)

如果去掉"使用node.js"的规定,这可能是一个有用的答案。如果它对你没有帮助,也许以后的游客会觉得它很有趣。

我已经为解决同样的问题(服务器端d3光栅化)工作了一段时间,我发现PhantomJS是最好的解决方案。

server.js:

var page = require('webpage').create(),
    renderElement = require('./renderElement.js'),
    Routes = require('./Routes.js'),
    app = new Routes();
page.viewportSize = {width: 1000, height: 1000};
page.open('./d3shell.html');
app.post('/', function(req, res) {
    page.evaluate(new Function(req.post.d3));
    var pic = renderElement(page, '#Viewport');
    res.send(pic);
});
app.listen(8000);
console.log('Listening on port 8000.');

Routes.js:https://gist.github.com/3061477
renderElement.js:https://gist.github.com/3176500

d3shell.html应该看起来像:

<!DOCTYPE HTML>
<html>
<head>
    <title>Shell</title>
</head>
<body>
    <div id="Viewport" style="display: inline-block"></div>
    <script src="http://cdnjs.cloudflare.com/ajax/libs/d3/2.8.1/d3.v2.min.js" type="text/javascript"></script>
</body>
</html>

然后,您可以使用phantomjs server.js和POST d3=[d3代码(渲染到#Viewport)启动服务器,服务器将使用base64编码的png进行响应。

(需要PhantomJS 1.7或更高版本。)

最新更新