'use strict';
// This example script reads a email message from a file as a stream and adds a link
// to all text/html nodes
const Rewriter = require('../lib/node-rewriter');
const Splitter = require('../lib/message-splitter');
const Joiner = require('../lib/message-joiner');
const iconv = require('iconv-lite');
const fs = require('fs');
let splitter = new Splitter();
let joiner = new Joiner();
// create a Rewriter for text/html
let rewriter = new Rewriter(node => ['text/html', 'text/plain', 'image/gif'].includes(node.contentType));
rewriter.on('node', data => {
// add a header to the current mime node
data.node.headers.add('X-Split', 'yes');
if (data.node.contentType === 'image/gif') {
data.decoder.pipe(fs.createWriteStream('test.gif'));
data.decoder.pipe(data.encoder);
return;
}
let chunks = [];
let chunklen = 0;
data.decoder.on('data', chunk => {
chunks.push(chunk);
chunklen += chunk.length;
});
data.decoder.on('end', () => {
let html = Buffer.concat(chunks, chunklen);
// html is a Buffer
if (data.node.charset) {
html = iconv.decode(html, data.node.charset);
} else {
html = html.toString('binary');
}
// enforce utf-8
data.node.setCharset('utf-8');
if (data.node.contentType === 'text/html') {
// append ad link to the HTML code
let adLink = 'Visit my Awesome homepage!!!!🐭
';
if (/<\/body\b/i.test(html)) {
// add before close
html.replace(/<\/body\b/i, match => '\r\n' + adLink + '\r\n' + match);
} else {
// append to the body
html += '\r\n' + adLink;
}
} else {
// append ad link to the HTML code
let adLink = 'Visit my Awesome homepage!!!! 🐭';
// append to the body
html += '\r\n' + adLink;
}
// return a Buffer
data.encoder.end(Buffer.from(html));
});
});
// pipe all streams together
fs.createReadStream(__dirname + '/message.eml')
.pipe(splitter)
.pipe(rewriter)
.pipe(joiner)
.pipe(process.stdout);