socket.io - Catch all event - events

I'm working on a Node.js application where pretty much all the communication is taking place via sockets.io.
What I need to do is, before processing any request (other than the login request) ensure that the user is authenticated.
The obvious way to do this would be to have a catch-all listener which is called prior to the execution of any method.
I can't seem to find anything like this in Socket.io, though. How can I achieve is? Is there a better approach than the one I'm taking?

The best approach here would be to authenticate the user upon connection (handshake), by parsing the cookie and decoding the session.
Read more about this in the following links:
http://www.danielbaulig.de/socket-ioexpress/ (this contains a detailed tutorial of everything you need to do)
https://github.com/LearnBoost/socket.io/wiki/Authorizing
socket.io and session?

Checkout out socket.io-events on nom for "Catching all events"
var router = requrie('socket.io-events')();
router.on('*', function (sock, args, cb) {
//do something with the args!
cb();
});
var io = require('socket.io')(3000);
Checkout out socket.io-handshake on nom for "socket.io v1.x session support"

Related

Which event type is triggered when a slack app is installed onto a workspace for the first time?

I'm trying to build an app that does something when it is first installed onto a workspace, eg: Ping every team member.
I couldn't find an event type that gets triggered upon app install:
https://api.slack.com/events
Is there a way to make this happen?
I think there might be a misunderstanding of the events concepts here. Events are always directly linked to one specific Slack app and needs to be processed by that very app. There is no such thing as "general" events for things happening on a workplace, like a new app being installed. Ergo there is no event for app installation.
Nevertheless you can implement the functionality you mentioned with Slack, e.g. pinging all team members once an app is first installed. All you need to do is include this function in the installation process of your Slack app and e.g. start pinging after the installation process is complete and the app verified that it was the first installation to this workspace. You do not need an event for that.
This is a partial answer because I was wondering the same thing and wanted to share what I found. On this oauth tutorial, it has the following code snippet:
app.get('/auth', function(req, res){
if (!req.query.code) { // access denied
return;
}
var data = {form: {
client_id: process.env.SLACK_CLIENT_ID,
client_secret: process.env.SLACK_CLIENT_SECRET,
code: req.query.code
}};
request.post('https://slack.com/api/oauth.access', data, function (error, response, body) {
if (!error && response.statusCode == 200) {
// Get an auth token
let oauthToken = JSON.parse(body).access_token;
// OAuth done- redirect the user to wherever
res.redirect(__dirname + "/public/success.html");
}
})
});
I believe instead of the line res.redirect(__dirname + "/public/success.html"); at that point you can make a request to ping everyone or even call a function to do so directly there, and it will trigger immediately once the app has been installed.

Should I use HTTP or xmlhttprequest on node.js? When?

I'm still exploring REST, node.js and generally web development. What I found out is that xmlhttprequest is mostly(if not always) used when using AJAX. As I learned AJAX is for asynchronous Javascript and XML. So my question is should I be using xmlhttprequest in my node.js project, just when I want to do asynchronous parts on my webpage? or does node.js HTTP also have opportunity to asynchronous javascript? How can I balance well the use of HTTP and xmlhttprequest(or AJAX) so that I don't get too messy in all my REST API stuff?
P.S. I kinda don't want to use AJAX, because of XML. I have heard that XML is much heavier in data than JSON and isn't worth using anymore. Is it true? What would you recommend me to do?
non async on node?
you're trying to build an endpoint api so all the other cases of not using async should be thrown out the window. As soon as you have a single non async code in your node.js project it will freeze the entire process until it is complete. Remember Node.js runs a single Thread (theoretically) which means all the other concurrent users are gonna get frozen.. that's one way to make people really upset.
say for instance you need to read a file from your Node.js server on a get request from a client (let's say a browser) well you want to make it a callback/promise never do non-async with an API server there is just no reason not to (in your case).
example below
import * as express from "express";
import * as fs from 'fs';
let app = express();
app.get('/getFileInfo', function(req, res) {
fs.readFile('filePath', 'UTF-8', function(err, data) {
if (err) {
console.log(err);
res.json({error: err});
} else {
res.json({data: data});
}
})
});
//users will freeze while the file is read until it is done reading
app.get('/nonasync', function(req, res) {
let data = fs.readFileSync('path', 'utf-8');
res.json({data:data});
});
the exact same idea applies to your web browser.. if you are going to not do something async in the browsers javascript the entire web application will be unresponsive because it also runs in the same manner, it has one main loop and unless they are in callbacks/promises/observable the website will freeze. Ajax is a much neater/nicer way to implement post/get/put/delete/get:id from a server then an XMLHttpRequest. now both of these have an option to send and receive JSON not only XML. Ajax is safer due to supporting different browser compatibility specs as XMLHttpRequest has some limitations in IE and Safari I believe.
NOTE: if you're not using a framework with node.js you should, it helps keep your endpoints neat and testable along with being able to pass the project on to others without them having to learn the way you implemented your req, res structure
some frameworks for node
Express 4 (my preference, api doc is really really good and strong
community)
Restify (used by Netflix - really light)
Hapi (never used but heard of)
some frameworks for web browsers you might like
angular 2 (my preference as I'm from a MEAN stack)
reactJS (created by big blue Facebook)
knockoutJS (simple and easy)
all the browser frameworks have their own implementation of the RESTful api's, but more are leaning towards Observable objects.

Detect url the user is viewing in chrome/firefox/safari

How can you detect the url that I am browsing in chrome/safari/firefox via cocoa (desktop app)?
As a side but related note, are there any security restrictions when developing a desktop app that the user will be alerted and asked if they want to allow? e.g. if the app accesses their contact information etc.
Looking for a cocoa based solution, not javascript.
I would do this as an extension, and because you would like to target Chrome, Safari, and Firefox, I'd use a cross-browser extension framework like Crossrider.
So go to crossrider.com, set up an account and create a new extension. Then open the background.js file and paste in code like this:
appAPI.ready(function($) {
appAPI.message.addListener({channel: "notifyPageUrl"}, function(msg) {
//Do something, like send an xhr post somewhere
// notifying you of the pageUrl that the user visited.
// The url is contained within msg.pageUrl
});
var opts = { listen: true};
// Note: When defining the callback function, the first parameter is an object that
// contains the page URL, and the second parameter contains the data passed
// to the context of the callback function.
appAPI.webRequest.onBeforeNavigate.addListener(function(details, opaqueData) {
// Where:
// * details.pageUrl is the URL of the tab requesting the page
// * opaqueData is the data passed to the context of the callback function
if(opaqueData.listen){
appAPI.message.toBackground({
msg: details.pageUrl
}, {channel: "notifyPageUrl"});
}
}, opts ); // opts is the opaque parameter that is passed to the callback function
});
Then install the extension! In the example above, nothing is being done with the detected pageUrl that the user is visiting, but you can do whatever you like here - you could send a message to the user, you could restrict access utilizing the cancel or redirectTo return parameters, you could log it locally utilizing the crossrider appAPI.db API or you could send the notification elsewhere, cross-domain, to wherever you like utilizing an XHR request from the background directly.
Hope that helps!
And to answer the question on security issues desktop-side, just note that desktop applications will have the permissions of the user under which they run. So if you are thinking of providing a desktop app that your users will run locally, say something that will detect urls they access by tapping into the network stream using something like winpcap on windows or libpcap on *nix varieties, then just be aware of that - and also that libpcap and friends would have to have access to a network card that can be placed in promiscuous mode in the first place, by the user in question.
the pcap / installed desktop app solutions are pretty invasive - most folks don't want you listening in on literally everything and may actually violate some security policies depending on where your users work - their network administrators may not appreciate you "sniffing", whether that is the actual purpose or not. Security guys can get real spooky so-to-speak on these kinds of topics.
The extension via Crossrider is probably the easiest and least intrusive way of accomplishing your goal if I understand the goal correctly.
One last note, you can get the current tab urls for all tabs using Crossrider's tabs API:
// retrieves the array of tabs
appAPI.tabs.getAllTabs(function(allTabInfo) {
// Display the array
for (var i=0; i<allTabInfo.length; i++) {
console.log(
'tabId: ' + allTabInfo[i].tabId +
' tabUrl: ' + allTabInfo[i].tabUrl
);
}
});
For the tab API, refer to:
http://docs.crossrider.com/#!/api/appAPI.tabs
For the background navigation API:
http://docs.crossrider.com/#!/api/appAPI.webRequest.onBeforeNavigate
And for the messaging:
http://docs.crossrider.com/#!/api/appAPI.message
And for the appAPI.db stuff:
http://docs.crossrider.com/#!/api/appAPI.db
Have you looked into the Scripting Bridge? You could have an app that launches, say, an Applescript which verifies if any of the well known browser is opened and ask them which documents (URL) they are viewing.
Note: It doesn't necessarily need to be an applescript; you can access the Scripting Bridge through cocoa.
It would, however, require the browser to support it. I know Safari supports it but ignore if the others do.
Just as a quick note:
There are ways to do it via AppleScript, and you can easily wrap this code into NSAppleScript calls.
Here's gist with AppleScript commands for Safari and Chrome. Firefox seems to not support AE.
Well obviously this is what I had come across on google.
chrome.tabs.
getSelected
(null,
function
(tab) {
alert
(tab.url);
}) ;
in pure javascript we can use
alert(document.URL);
alert(window.location.href)
function to get current url

I want my Domino Servlet to get an authenticated user session

It seems a like a pretty fundamental question, in a running Servlet hosted on Domino I want to access Domino resources that I have wisely protected using the the very fine security of IBM Notes and Domino.
I want the Servlet to be able to read and write data to Domino whilst keeping that data from the client that called the Servlet (or xAgent) and preventing the client from writing directly.
I'd be happy to be able to get a session that represented the signer of the application. I can get a session for a registered user by calling the Servlet using ?open&login and signing in. That's not practical.
I've looked here: How can you use SessionAsSigner in a Java Bean called from an XPage? where Mark Leusink (https://stackoverflow.com/users/1177870/mark-leusink) implies the use of ExtLib's getCurrentSessionAsSigner() could be used. I've tried it, having signed the whole application with a single user id and it doesn't return a session. The answer seems to lie in the Servlet's inability to get a FacesContext object.
This feels like the answer should be obvious but it isn't to me. Any ideas?
FacesContext is JSF stuff and can be used from XAgent (=XPage).
In a servlet you can do this:
Session session = NotesFactory.createSession(null, "user", "password");
Server ID usually has no password and doing this will use the server ID:
Session session = NotesFactory.createSession();
Check the source of the WebDav project on OpenNTF. It has all the code you need
There have been lots of good answers to the original question. Thanks very much.
The solution I propose to use is to port the code I have to OSGi plugins. It appears that java code/Servlets within the NSF context are subject to security controls that are relaxed when the same code runs within the OSGi context. The code:
try {
NotesThread.sinitThread();
Session s = NotesFactory.createSession("","<my username>","<my password>");
.....
session = null;
} catch (Exception e) {
} finally {
NotesThread.stermThread();
}
Runs fine in the OSGI context, but within in an NSF produc
com.ibm.domino.osgi.core.context.ContextInfo.getUserSession()
Jason - I assume you basically want the same functionality you would get running a Web Query Save agent if you didn't select run as Web User selected, in other words as the signer of the code.
You could try setting up a internet site rule to allow basic authentication for the specific application path you wanted to use - might be worth using a subdomain for this.
Then within the Servlet call this URL, whilst setting the Basic authorization parameters (username & password).
Something like this.
URL url = new URL(URL_TO_CALL);
String authStr = "USERNAME:PASSWORD";
String authEncoded = Base64.encodeBytes(authStr.getBytes());
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setDoOutput(true);
connection.setRequestProperty("Authorization", "Basic " + authEncoded);
InputStream is = connection.getInputStream();

Monitor file change through AJAX, how?

I'm looking for a way through AJAX (not via a JS framework!) to real time monitor a file for changes. If changes where made to that file, I need it to give an alert message. I'm a total AJAX noob, so please be gentle. ;-)
Edit: let me explain the purpose a bit more in detail. I'm using a chat script I've written in PHP for a webhop, and what I want is from an admin module monitor the chat requests. The chats are stored in text files, and if someone starts a chat session a new file is created. If that's the case, in the admin module I want to see that in real time.
Makes sense?
To monitor a file for changes with AJAX you could do something like this.
var previous = "";
setInterval(function() {
var ajax = new XMLHttpRequest();
ajax.onreadystatechange = function() {
if (ajax.readyState == 4) {
if (ajax.responseText != previous) {
alert("file changed!");
previous = ajax.responseText;
}
}
};
ajax.open("POST", "foo.txt", true); //Use POST to avoid caching
ajax.send();
}, 1000);
I just tested it, and it works pretty well, but I still maintain that AJAX is not the way to go here. Comparing file contents will be slow for big files. Also, you mentionned no framework, but you should use one for AJAX, just to handle the cross-browser inconsistencies.
AJAX is just a javascript, so from its definition you do not have any tool to get access to file unless other service calls an js/AJAX to notify about the change.
I've done that from scratch recently.
I don't know how much of a noob you are with PHP (it's the only server script language I know), but I'll try to be as brief as possible, feel free to ask any doubt.
I'm using long polling, which consists in this (
Create a PHP script that checks the content of the file periodically and only responds when it sees any change (it could include a description of the change in the response)
Create your XHR object
Include your notification code as a callback function (it can use the description)
Make the request
The PHP script will start checking the file, but won't reply until there is a change
When it responds, the callback will be called and your notification code will launch
If you don't care about the content of the file, only that it has been changed, you can check the last-modified time instead of the content in the PHP script.
EDIT: from some comment I see there's something to monitor file changes called FAM, that seems to be the way to go for the PHP script

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