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Running a NodeJS cron from cron-job.org

I am trying to run a NodeJS cron at a set interval using cron-job.org, but they don't have any documentation about how to actually run the script.
Basically the service visits a URL that you provide at a set interval, but I am specifically confused about what kind of code I can put on the endpoint (specifically what type of code will actually run). Can someone provide an example of what I would put at the endpoint URL?

You can do something really simple using either the HTTP module in Node.js or the popular Express module. Using express you can do something really simple like:
var express = require('express');
var app = express();
app.get("/test", function(req, res, next){
res.setHeader('Content-Type', 'application/json');
res.send(JSON.stringify({ status: 'OK', timeStamp: new Date().toISOString() }));
});
console.log('Express listening.. on 3000');
app.listen(3000);
You can really run anything you like in the /test endpoint, though when it's being called from cron-job.org they'll probably stop if you keep throwing back 400 errors at them or the script takes really long to execute.
You'd call this using the url
http://yourdomain:3000/test
And of course you might well want to change the port number and path!

cron-job.org only allows you to call an endpoint at a set time interval.
If you want to have some code run at a set interval without worrying about HTTP server, deploying, etc... Check out services like chunk.run
Here's an example code:
https://chunk.run/c/scheduled-run-example
Then you can just select the trigger "Scheduled" like so:

What's the most efficient way to call a Node.js backend function with JavaScript

I'm an html5 developer with mainly JavaScript experience. I'm starting to learn the backend using Node.js. I don't have a particular example of this question/requirements. I'd like to call a back end function with JavaScript, but I'm not sure how. I already researched events and such for Node.js, but I'm still not sure how to use them.

Communicating with node.js is like communicating with any other server side technology.. you would need to set up some form of api. What kind you need would depend on your use case. This would be a different topic but a hint would be if you need persistent connections go with web sockets and if you just need occasional connections go with rest. Here is an example of calling a node function using a rest api and express.
var express = require('express');
var app = express();
app.post('/api/foo', foo);
function foo(req, res){
res.send('hello world');
};
app.listen(3000);
From the frontend you can post to this REST endpoint like so.
$.post("/api/foo", function(data) {
console.log( "Foo function result:", data );
});

If you're just starting with node-js, don't worry about Websockets just yet.
You're going to want to create a REST API (most likely) depending on what you're trying to accomplish. You can put that REST API behind some kind of authentication if desired.
A REST API is going to have endpoints for creating/deleting/updating and getting (finding) a document, like a given user.
My recommendation is to work backwards from something that's already working. Clone this app locally and check out the controllers to see examples of how this application interacts with creating users.
https://github.com/sahat/hackathon-starter
Once you create a controller that returns data when a client hits an endpoint (like http://localhost:3000/user/create ) , you'll want to create some HTML that will interact with endpoint through a form HTML element. Or you can interact with that endpoint with Javascript using a library like jQuery.
Let me know if that makes sense to you. Definitely a good starting point is to clone that app and work backwards from there.

Can I suggest trying api-mount. It basically allows calling API as simple functions without having to think about AJAX requests, fetch, express, etc. Basically in server you do:
const ApiMount = apiMountFactory()
ApiMount.exposeApi(api)
"api" is basically an object of methods/functions that you are willing to call from your web application.
On the web application you then do this:
const api = mountApi({baseUrl: 'http://your-server.com:3000'})
Having done that you can call your API simply like this:
const result = await api.yourApiMethod()
Try it out. Hope it helps.

AngularJS - Best Way to Handle State on Manually Entered URLs

I currently have a set-up based on the meanjs stack boilerplate where I can have users logged in this state of being 'logged-in' stays as I navigate the URLs of the site. This is due to holding the user object in a Service which becomes globally available.
However this only works if I navigate from my base root, i.e. from '/' and by navigation only within my app.
If I manually enter a URL such as '/page1' it loses the global user object, however if I go to my root homepage and navigate to '/page1' via the site. Then it's fine, it sees the global user object in the Service object.
So I guess this happens due to the full page refresh which loses the global value where is navigating via the site does not do a refresh so you keep all your variables.
Some things to note:
I have enabled HTML5Mode, using prefix of '!'.
I use UI-Router
I use a tag with '/'
I have a re-write rule on express that after loading all my routes, I have one last route that takes all '/*' to and sends back the root index.html file, as that is where the angularjs stuff is.
I'm just wondering what people generally do here? Do they revert the standard cookies and local storage solutions? I'm fairly new to angular so I am guessing there are libraries out there for this.
I just would like to know what the recommended way to deal with this or what the majority do, just so I am aligned in the right way and angular way I suppose.
Update:
If I manually navigate to another URL on my site via the address bar, I lose my user state, however if I manually go back to my root via the address bar, my user state is seen again, so it is not simply about loosing state on window refresh. So it seems it is related to code running on root URL.
I have an express re-write that manually entered URLs (due to HTML5 Location Mode) should return the index.html first as it contains the AngularJs files and then the UI-Route takes over and routes it properly.
So I would have expected that any code on the root would have executed anyway, so it should be similar to navigating via the site or typing in the address bar. I must be missing something about Angular that has this effect.
Update 2
Right so more investigation lead me to this:
<script type="text/javascript">
var user = {{ user | json | safe }};
</script>
Which is a server side code for index.html, I guess this is not run when refreshing the page to a new page via a manual URL.
Using the hash bang mode, it works, which is because with hash bang mode, even I type a URL in the browser, it does not cause a refresh, where as using HTML5 Mode, it does refresh. So right now the solution I can think of is using sessionStorage.
Unless there better alternatives?
Update 3:
It seems the best way to handle this when using HTML5Mode is that you just have to have a re-write on the express server and few other things.

I think you have it right, but you may want to look at all the routes that your app may need and just consider some basic structure (api, user, session, partials etc). It just seems like one of those issues where it's as complicated as you want to let it become.
As far as the best practice you can follow the angular-fullstack-generator or the meanio project.
What you are doing looks closest to the mean.io mostly because they also use the ui-router, although they seem to have kept the hashbang and it looks like of more of an SEO friendly with some independant SPA page(s) capability.
You can probably install it and find the code before I explained it here so -
npm install -g meanio
mean init name
cd [name] && npm install
The angular-fullstack looks like this which is a good example of a more typical routing:
// Server API Routes
app.route('/api/awesomeThings')
.get(api.awesomeThings);
app.route('/api/users')
.post(users.create)
.put(users.changePassword);
app.route('/api/users/me')
.get(users.me);
app.route('/api/users/:id')
.get(users.show);
app.route('/api/session')
.post(session.login)
.delete(session.logout);
// All undefined api routes should return a 404
app.route('/api/*')
.get(function(req, res) {
res.send(404);
});
// All other routes to use Angular routing in app/scripts/app.js
app.route('/partials/*')
.get(index.partials);
app.route('/*')
.get( middleware.setUserCookie, index.index);
The partials are then found with some regex for simplicity and delivered without rendering like:
var path = require('path');
exports.partials = function(req, res) {
var stripped = req.url.split('.')[0];
var requestedView = path.join('./', stripped);
res.render(requestedView, function(err, html) {
if(err) {
console.log("Error rendering partial '" + requestedView + "'\n", err);
res.status(404);
res.send(404);
} else {
res.send(html);
}
});
};
And the index is rendered:
exports.index = function(req, res) {
res.render('index');
};

In the end I did have quite a bit of trouble but managed to get it to work by doing few things that can be broken down in to steps, which apply to those who are using HTML5Mode.
1) After enabling HTML5Mode in Angular, set a re-write on your server so that it sends back your index.html that contains the Angular src js files. Note, this re-write should be at the end after your static files and normal server routes (e.g. after your REST API routes).
2) Make sure that angular routes are not the same as your server routes. So if you have a front-end state /user/account, then do not have a server route /user/account otherwise it will not get called, change your server-side route to something like /api/v1/server/route.
3) For all anchor tags in your front-end that are meant to trigger a direct call to the server without having to go through Angular state/route, make sure you add a 'target=_self'.

Multipage Node.js Server Without Routing Bloat?

Can I set up a multipage Node.js web server that does not require a unique route for every page?
I have a simple HTTP server set up using Node and Express, using EJS for view engine. My routing currently looks like this:
// routing
app.get('/', routes.index);
app.get('/hig', routes.hig);
app.get('/proto', routes.proto);
app.get('/design', routes.design);
app.get('/process', routes.process);
app.get('/demo', routes.demo);
app.get('/api', api.index);
app.get('/api/rules', api.list);
app.get('/api/rules/:id', api.ruleid);
I'd like to be able to easily update my site to have pages such as /hig/section1 and /hig/section2 (and so on) without having to update the route table each time and restart the server. More importantly, I'd like to be able to quickly and easily make multiple versions of a demo and be able to link to them.
For example, create a new demo and link a user to /demo/version23 while linking someone else to /demo/version 35, allowing me to illustrate different functionality without breaking previous demo sites. It would not be long until /demo/version108 and beyond exist, so having a sane way to create these without having 108+ routes is preferable.
The only method I've been successful at so far is updating route tables. Is there another way I can point to different pages in the route table that will allow me to more easily add new pages?

You should consider making part of url variable for ex as /hig/:section.
You should then get section as a parameter which you can use to map to different content, page or do any other logic that you want with that.

In my express api, I have a wildcard get. The endpoint var parses the keyword and then whatever you decided to do with that is up to you. In mine I have some if statements to change the database model etc but you don't need that... I would suggest keeping the 404 send, so if somebody hits an undesired url you can just give them whatever status code.
app.get('/:endpoint', function (req, res) {
var endpoint = req.params.endpoint;
if( endpoint == 'something' ){
} else if( endpoint == 'something' ){
} else { return res.send(404, { erorr: "That resource doesn't exist" }); }
// Display the results
});

I implemented simple demo project to achieve multi-app structure.
https://github.com/hitokun-s/node-express-multiapp-demo
With this structure, you can easily set up and maintain each app independently.
I hope this would be a help for you.

Node.js Programming Pattern for getting Execution Context

I am writing a web app in node.js. Now every processing on the server is always in the context of a session which is either retrieved or created at the very first stage when the request hits the server. After this the execution flows through multiple modules and callbacks within them. What I am struggling with is in creating a programming pattern so that at any point in the code the session object is available without the programmer requiring it to pass it as an argument in each function call.
If all of the code was in one single file I could have had a closure but if there are function calls to other modules in other files how do I program so that the session object is available in the called function without passing it as an argument. I feel there should be some link between the two functions in the two files but how to arrange that is where I am getting stuck.
In general I would like to say there is always a execution context which could be a session or a network request whose processing is spread across multiple files and the execution context object is to be made available at all points. There can actually be multiple use cases like having one Log object for each network request or one Log object per session. And the plumbing required to make this work should be fitted sideways without the application programmer bothering about it. He just knows that that execution context is available at all places.
I think it should fairly common problem faced by everyone so please give me some ideas.
Following is the problem
MainServer.js
app = require('express').createServer();
app_module1 = require('AppModule1');
var session = get_session();
app.get('/my/page', app_module1.func1);
AppModule1.js
app_module2 = require('AppModule2');
exports.func1 = function(req,res){
// I want to know which the session context this code is running for
app_module2.func2(req,res);
}
AppModule2.js
exports.func2 = function(req,res){
// I want to know where the session context in which this code is running
}

You can achieve this using Domains -- a new node 0.8 feature. The idea is to run each request in it's own domain, providing a space for per-request data. You can get to the current request's domain without having to pass it all over via process.domain.
Here is an example of getting it setup to work with express:
How to use Node.js 0.8.x domains with express?
Note that domains in general are somewhat experimental and process.domain in particular is undocumented (though apparently not going away in 0.8 and there is some discussion on making it permanent). I suggest following their recommendation and adding an app-specific property to process.domain.data.
https://github.com/joyent/node/issues/3733
https://groups.google.com/d/msg/nodejs-dev/gBpJeQr0fWM/-y7fzzRMYBcJ

Since you are using Express, you can get session attached to every request. The implementation is following:
var express = require('express');
var app = express.createServer();
app.configure('development', function() {
app.use(express.cookieParser());
app.use(express.session({secret: 'foo', key: 'express.sid'}));
});
Then upon every request, you can access session like this:
app.get('/your/path', function(req, res) {
console.log(req.session);
});
I assume you want to have some kind of unique identifier for every session so that you can trace its context. SessionID can be found in the 'express.sid' cookie that we are setting for each session.
app.get('/your/path', function(req, res) {
console.log(req.cookies['express.sid']);
});
So basically, you don't have to do anything else but add cookie parser and enable sessions for your express app and then when you pass the request to these functions, you can recognize the session ID. You MUST pass the request though, you cannot build a system where it just knows the session because you are writing a server and session is available upon request.

What express does, and the common practice for building an http stack on node.js is use http middleware to "enhance" or add functionality to the request and response objects coming into the callback from your server. It's very simple and straight-forward.
module.exports = function(req, res, next) {
req.session = require('my-session-lib');
next();
};
req and res are automatically passed into your handler, and from their you'll need to keep them available to the appropriate layers of your architecture. In your example, it's available like so:
AppModule2.js
exports.func2 = function(req,res){
// I want to know where the session context in which this code is running
req.session; // <== right here
}

Nodetime is a profiling tool that does internally what you're trying to do. It provides a function that instruments your code in such a way that calls resulting from a particular HTTP request are associated with that request. For example, it understands how much time a request spent in Mongo, Redis or MySQL. Take a look at the video on the site to see what I mean http://vimeo.com/39524802.
The library adds probes to various modules. However, I have not been able to see how exactly the context (url) is passed between them. Hopefully someone can figure this out and post an explanation.
EDIT: Sorry, I think this was a red-herring. Nodetime is using the stack trace to associate calls with one another. The results it presents are aggregates across potentially many calls to the same URL, so this is not a solution for OP's problem.