在Firebase云功能中创建PDF

Question

我是javascript的新手,我正在尝试使用pdfkit从firebase函数制作PDF文件.下面是我的功能代码.

const pdfkit = require('pdfkit');
const fs = require('fs');

exports.PDFTest = functions.https.onRequest((req, res) => {

var doc = new pdfkit();

var loremIpsum = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam in...';  

doc.y = 320;
doc.fillColor('black')
doc.text(loremIpsum, {
paragraphGap: 10,
indent: 20,
align: 'justify',
columns: 2
});  

doc.pipe( res.status(200) )

});

该函数启动但发生超时错误.这是在firebase中创建pdf文件的最佳方式吗？我有一些html,我想做成一个PDF文件.

Answer 1

我也在研究这个问题,下面你可以找到一个云功能样本,它是从firebase存储上托管的模板HTML创建一个PDF文件.它使用Hanldebars将一些数据应用于模板,然后在firebase存储上再次上传.我在这里使用了node-html-pdf.

const functions = require('firebase-functions');
const admin = require('firebase-admin');
const pdf = require('html-pdf');
const gcs = require('@google-cloud/storage')({
  projectId: '[YOUR PROJECT ID]',
  //key generated from here https://console.firebase.google.com/project/_/settings/serviceaccounts/adminsdk?authuser=1
  keyFilename: '[YOUR KEY]'
});
const handlebars = require('handlebars');
const path = require('path');
const os = require('os');
const fs = require('fs');
const bucket = gcs.bucket('[YOUR PROJECT ID].appspot.com');

admin.initializeApp(functions.config().firebase);

exports.helloWorld = functions.https.onRequest((request, response) => {
  // data to apply to template file
  const user = {
    "date": new Date().toISOString(),
    "firstname" : "Guillaume",
  };
  const options = {
    "format": 'A4',
    "orientation": "portrait"
  };
  const localTemplate = path.join(os.tmpdir(), 'localTemplate.html');
  const localPDFFile = path.join(os.tmpdir(), 'localPDFFile.pdf');

  bucket.file('template.html').download({ destination: localTemplate }).then(() => {
    console.log("template downloaded locally");
    const source = fs.readFileSync(localTemplate, 'utf8');
    const html = handlebars.compile(source)(user);
    console.log("template compiled with user data", html);

    pdf.create(html, options).toFile(localPDFFile, function(err, res) {
      if (err){
        console.log(err);
        return response.send("PDF creation error");
      }
      console.log("pdf created locally");

      return bucket.upload(localPDFFile, { destination: user.name + '.pdf', metadata: { contentType: 'application/pdf'}}).then(() => {
        response.send("PDF created and uploaded!");
      }).catch(error => {
        console.error(error);
        response.send("PDF created and uploaded!");
      });
  });
  });
});

希望这将有助于下一个这样做:)

Answer 2

也只是在做这个，为了将 PDF 保存在存储中，它的工作方式是这样的

const myPdfFile = admin.storage().bucket().file('/test/Arbeitsvertrag.pdf');
const doc = new pdfkit();
const stream = doc.pipe(myPdfFile.createWriteStream());
doc.fontSize(25).text('Test 4 PDF!', 100, 100);
doc.end();

return res.status(200).send();

猜猜您应该等到流关闭并侦听错误和事物，但这是我能够制作的第一个工作示例，现在正在研究如何将图像从存储中获取到 PDF 中。