route.js

const jsreport = require("jsreport-core")();
const { fetchReportTemplate } = require("../reports/report-template");
const router = require('express').Router()
const fs = require('fs');
const express = require('express');
const path = require('path');

const reportingApp = express();
jsreport.use(require('jsreport-express')({ app: reportingApp }));
jsreport.use(require('jsreport-chrome-pdf')());
jsreport.use(require('jsreport-handlebars')());
jsreport.use(require('jsreport-templates')());
jsreport.use(require('jsreport-assets')());

let jsreportStarted = false;

const initReport = () => {
    if (jsreportStarted) {
        return Promise.resolve(jsreport);
    }
    console.log('initializing jsreport');
    jsreportStarted = true;
    return jsreport.init();
};

router.get("/map-images", (req, res, next) => {
    // readFiles(reqPath)
    initReport().then(() => {
        let assets = jsreport.documentStore.collection('assets').find();
        let resolved = assets.then((a) => a);
        resolved = resolved.map(a => a.name).filter(a => /.png$/.test(a))
        return jsreport.render({
            template: {
                content: fetchReportTemplate("map"),
                engine: "handlebars",
                recipe: "chrome-pdf"
            },
            assets: resolved
        }).then((out) => {
            // const data = resp.content;
            // // console.log(data.toString())
            res.writeHead(200, {
                "Content-Type": "application/pdf",
                "Content-disposition": "attachment;filename=" + "done",
                "Content-Length": out.length
            });
            // out.stream.pipe(res);        

            // res.end(new Buffer(data, "binary"));
            // fs.writeFile('test.pdf', out.toString(), 'binary');
            res.send(new Buffer(data.toString(), 'binary'))             
            // res.write(data.toString(), 'binary');             
        });
    }).catch(function (e) {
        res.end(e.message)
    })
    // next(); 
})

fetchReportTemplate.js

const fs = require("fs");
const path = require("path");


function fetchReportTemplate(templateName) {
    const file = path.join(__dirname, `${templateName}.html`);
    const content = fs.readFileSync(file, "utf8");
    return content;
}

module.exports = { fetchReportTemplate }