jsreport Hello world - node.js

Question

I'm trying to create my first report with jsreport. I've followed the documentation, but I'm not able to generate the most simple Hello world.
I've tried:
npm install jsreport
and then create a simple server:
var http = require('http');
var jsreport = require('jsreport');
http.createServer(function (req, res) {
jsreport.render("<h1>Hello world</h1>").then(function(out) {
out.stream.pipe(res);
}).catch(function(e) {
res.end(e.message);
});
}).listen(1337, '127.0.0.1');
The server is running on port 1337.
But if I try to open http://localhost:1337/ nothing happens. I was expecting a page with Hello world.
On the server side, I get on the console:
2018-02-17T10:55:16.009Z - info: Initializing jsreport#1.10.0 in development mode using configuration file: jsreport.config.json
2018-02-17T10:55:16.011Z - info: Setting process based strategy for rendering. Please visit http://jsreport.net/learn/configuration for information how to get more performance.
2018-02-17T10:55:16.013Z - info: Searching for available extensions in /home/jgr/WebstormProjects/GeoMasterBoard/server/
2018-02-17T10:55:16.016Z - info: Extensions location cache not found, crawling directories
Do I need a jsreport server running or this code should be enough?
I also tried to install jsreport server, following the documentation.
After jsreport start it shows on the console:
2018-02-17T10:42:46.013Z - info: Initializing jsreport#1.10.0 in development mode using configuration file: jsreport.config.json
2018-02-17T10:42:46.015Z - info: Setting process based strategy for rendering. Please visit http://jsreport.net/learn/configuration for information how to get more performance.
2018-02-17T10:42:46.023Z - info: Searching for available extensions in /home/jgr/WebstormProjects/GeoMasterBoard/server/
2018-02-17T10:42:46.025Z - info: Extensions location cache not found, crawling directories
But nothing happens when I try to open http://localhost:5488/. If I do: nmap -p 5488 localhost the awnser is:
PORT STATE SERVICE
5488/tcp closed unknown
What am I missing?
I'm using node.js v8.1.2, on Ubuntu 16.04.

Answer 1

your code is not working because the following reasons:
when you open your browser at http://localhost:1337/ your browser is actually making 3 different requests (1-> http://localhost:1337/, 2-> http://localhost:1337/favicon.ico, 3-> http://localhost:1337/robots.txt), not just one
the code that your are using to handle the http server is not doing a proper routing, it should process a url just once, right now it is just calling jsreport.render on every single request that goes through your server (even the ones for /favicon.ico, /robots.txt), and this is bad in the browser because as i already explained your browser makes like 3 request for a single page load.
you are using the shortcut jsreport.render in the request handling, which means that jsreport is going to try to initialize itself when your first request arrives, because of the problem explained above (not doing a proper routing in your http server) this results in jsreport trying to initialize 3 times on your first page load which leads to an uncaught exception that exits your process with no error message (we are going to update some things to better handling this exception in the future).
finally, here is some code that completes your hello world test case (with some code that filters unwanted requests like /robots.txt, /favicon.ico, but in production code you should implement a proper router logic in your http server. if you don't want to code it yourself just use something like express)
var http = require('http');
var jsreport = require('jsreport');
http.createServer(function(req, res) {
if (req.url !== '/') {
return console.log('ignoring request:', req.url);
}
console.log('request:', req.url);
jsreport
.render('<h1>Hello world</h1>')
.then(function(out) {
out.stream.pipe(res);
})
.catch(function(e) {
res.end(e.message);
});
}).listen(1337, '127.0.0.1');