dougal-software/lib/www/server/api/middleware/event/get/pdf.js

const fs = require('fs/promises');
const Path = require('path');
const crypto = require('crypto');
const { event, sequence, configuration } = require('../../../../lib/db');
const { transform } = require('../../../../lib/sse');
const render = require('../../../../lib/render');
const { url2pdf } = require('../../../../lib/selenium');

function tmpname (tmpdir="/dev/shm") {
	return Path.join(tmpdir, crypto.randomBytes(16).toString('hex')+".tmp");
}

const pdf = async function (req, res, next) {
	const fname = tmpname();
	try {
		const query = req.query;
		query.sequence = req.params.sequence;
		const events = await event.list(req.params.project, query);
		const sequences = await sequence.list(req.params.project, query);
		const seis = transform(events, sequences, {projectId: req.params.project});
		const templates = await configuration.get(req.params.project, "sse/templates");
		const template = templates[0].template;
		
		const html = await render(seis, template);
		
		await fs.writeFile(fname, html);
		const pdf = Buffer.from(await url2pdf("file://"+fname), "base64");
		
		res.status(200).send(pdf);
		next();
	} catch (err) {
		if (err.message.startsWith("template")) {
			next({message: err.message});
		} else {
			next(err);
		}
	} finally {
		await fs.unlink(fname);
	}
};

module.exports = pdf;