overleaf/services/filestore/app/coffee/FileConverter.js

/*
 * decaffeinate suggestions:
 * DS102: Remove unnecessary code created because of implicit returns
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
const _ = require("underscore");
const metrics = require("metrics-sharelatex");
const logger = require("logger-sharelatex");
const safe_exec = require("./SafeExec");
const approvedFormats = ["png"];
const Settings = require("settings-sharelatex");

const fourtySeconds = 40 * 1000;

const childProcessOpts = {
	killSignal: "SIGTERM",
	timeout: fourtySeconds
};


module.exports = {

	convert(sourcePath, requestedFormat, callback){
		logger.log({sourcePath, requestedFormat}, "converting file format");
		const timer = new metrics.Timer("imageConvert");
		const destPath = `${sourcePath}.${requestedFormat}`;
		sourcePath = `${sourcePath}[0]`;
		if (!_.include(approvedFormats, requestedFormat)) {
			const err = new Error("invalid format requested");
			return callback(err);
		}
		const width = "600x";
		let command = ["convert", "-define", `pdf:fit-page=${width}`, "-flatten", "-density", "300", sourcePath, destPath];
		command = Settings.commands.convertCommandPrefix.concat(command);
		return safe_exec(command, childProcessOpts, function(err, stdout, stderr){
			timer.done();
			if (err != null) {
				logger.err({err, stderr, sourcePath, requestedFormat, destPath},  "something went wrong converting file");
			} else {
				logger.log({sourcePath, requestedFormat, destPath},  "finished converting file");
			}
			return callback(err, destPath);
		});
	},

	thumbnail(sourcePath, callback){
		const destPath = `${sourcePath}.png`;
		sourcePath = `${sourcePath}[0]`;
		const width = "260x";
		let command = ["convert", "-flatten", "-background", "white", "-density", "300", "-define", `pdf:fit-page=${width}`, sourcePath, "-resize", width, destPath];
		logger.log({sourcePath, destPath,  command}, "thumbnail convert file");
		command = Settings.commands.convertCommandPrefix.concat(command);
		return safe_exec(command, childProcessOpts, function(err, stdout, stderr){
			if (err != null) {
				logger.err({err, stderr, sourcePath}, "something went wrong converting file to thumbnail");
			} else {
				logger.log({sourcePath, destPath}, "finished thumbnailing file");
			}
			return callback(err, destPath);
		});
	},	

	preview(sourcePath, callback){
		logger.log({sourcePath}, "preview convert file");
		const destPath = `${sourcePath}.png`;
		sourcePath = `${sourcePath}[0]`;
		const width = "548x";
		let command = ["convert", "-flatten", "-background", "white", "-density", "300", "-define", `pdf:fit-page=${width}`, sourcePath, "-resize", width, destPath];
		command = Settings.commands.convertCommandPrefix.concat(command);
		return safe_exec(command, childProcessOpts, function(err, stdout, stderr){
			if (err != null) {
				logger.err({err, stderr, sourcePath, destPath}, "something went wrong converting file to preview");
			} else {
				logger.log({sourcePath, destPath}, "finished converting file to preview");
			}
			return callback(err, destPath);
		});
	}
};