in
ecosystem
How to connect them and when it might be useful?
Michał Michalczuk
Michał Michalczuk
Senior JavaScript Developer
Ciklum / Stibo Systems
IT trainer
infoShare Academy
in
ecosystem
How to connect them and when it might be useful?
Michał Michalczuk
Why we'd like to use
over ?
Performance ?
Performance ?
Easy setup?
const express = require('express');
const app = express();
const port = 3000;
app.get('/api/greeter', (req, res) => res.send({
message: `Hello ${req.query.name}!`
}));
app.listen(port, () => console.log(`Example app listening on port ${port}!`));{
"name": "expressjs-example",
"version": "1.0.0",
"main": "index.js",
"scripts": {
"start": "node server.js"
},
"dependencies": {
"express": "^4.16.3"
}
}
Easy setup?
const express = require('express');
const app = express();
const port = 3000;
app.get('/api/greeter', (req, res) => res.send({
message: `Hello ${req.query.name}!`
}));
app.listen(port, () => console.log(`Example app listening on port ${port}!`));{
"name": "expressjs-example",
"version": "1.0.0",
"main": "index.js",
"scripts": {
"start": "node server.js"
},
"dependencies": {
"express": "^4.16.3"
}
}
Marian
The case
In
I almost forgot - we don't have the money for license.
Just find some opensource.
In
I almost forgot - we don't have the money for license.
Just find some opensource.
What we can use in JS world?
Options in Node.js
Puppeteer is a Node library which provides a high-level API to control Chrome or Chromium
PhantomJS is a headless web browser scriptable with JavaScript.
PhantomJS development is suspended until further notice
But why web browser?
How to connect
with
(just - how to solve our problem)
-
Separate Node.js service
-
Azure Function
-
NodeServices in Asp.Net Core
It is an example use case
...but with quite unique problems
HtmlToPdf
Quotes
Node Services / JavaScript Services
nuget package: Microsoft.AspNetCore.NodeServices
Requirements
-
Node.js
- Note: If you're deploying to an Azure web site, you don't need to do anything here - Node is already installed and available in the server environments
- Current Azure node version - 10.14.x
-
.NET
- For .NET Core (e.g., ASP.NET Core apps), you need at least 1.0 RC2
- For .NET Framework, you need at least version 4.5.1.
What they can do?
Webpack dev middleware
HMR
SSR
Server Side Pre-rendering
Run any Node.js code
module.exports = function(callback) {
// In this trivial example, we don't need to receive any
// parameters - we just send back a string
var message = 'Hello from Node at ' + new Date().toString();
callback(/* error */ null, message);
};NodeScripts/my-script.js
public async Task<string> About(
[FromServices] INodeServices nodeServices)
{
return await nodeServices.InvokeAsync<string>(
"NodeScripts/my-script.js"
);
}Controllers/MyController.cs
NodeServices has a pluggable hosting/transport mechanism, because it is an abstraction over various possible ways to invoke Node.js from .NET.
...all the built-in hosting mechanisms work by launching Node as a separate process on the same machine as your .NET code.
Other options to run
on
Edge is a bridge
using EdgeJs;
public static async void Start()
{
var func = Edge.Func(@"
return function (data, cb) {
cb(null, 'Node.js ' +
process.version +
' welcomes ' +
data);
}
");
Console.WriteLine(await func(".NET"));
}var edge = require('edge');
var helloWorld = edge.func(`
async (input) => {
return ".NET Welcomes " + input.ToString();
}
`);
helloWorld('JavaScript', function (error, result) {
if (error) throw error;
console.log(result);
});
Sum it up
Its worth to run JS code in .Net ... if
- You already wrote it
- You want to use some unique packages
What to use?
- Azure Function - looks nice, remember about cold start
- Asp.Net JavaScriptServices/NodeServices - easy and nice
- Edge.js - if you need both ways bridge
Remember about sandbox
Other solutions for HTML -> PDF
- AWS Lambda with Puppeteer: https://github.com/sambaiz/puppeteer-lambda-starter-kit
- Puppeteer-Sharp: https://github.com/kblok/puppeteer-sharp
Helpful links
-
https://github.com/aspnet/JavaScriptServices/tree/master/src/Microsoft.AspNetCore.NodeServices
-
https://docs.microsoft.com/en-us/azure/azure-functions/functions-run-local
-
https://docs.microsoft.com/en-us/azure/azure-functions/functions-reference-node
-
https://gldraphael.com/blog/generating-pdfs-from-an-asp-net-core-app-using-a-node-library/
Feedback*
*thing which speakers need
Michał Michalczuk
michalczukm.xyz
Thank you!
michalczukm
