ExpressJS, MongoDB + Socket.IO - Identify Individual User Session - node.js

I'm using https://github.com/sahat/hackathon-starter/tree/es6. I added Socket.IO but can't figure out a way to safely get current logged in user information . I have a button that when pressed I want to send to the server (Username, Balance, and Amount so I can update their Schema model safely ... So far i was able to so with Jade but I'm sure this is really bad .
JADE:
.content-r-inner.child
.col-md-12.col-xs-12.col-lg-12.no-pad-home
if !user
include partials/flash
include partials/visitorbar
else
include partials/userbar
|
#time.timecontainer.pulsing.pulsingbox
|
.product Product:
|
input#amount(type='text')
|
#slider-range-max
|
#minus1.minus.unselectable -
|
#plus1.plus.unselectable +
// </div>
.sendAmount(onclick="GetAmount()")
// inside include partials/userbar I have GetAmount Function
function GetAmount(){
socket.emit('getAmount', {
"username": "#{user.username}",
"maxBalance": "#{user.balance}",
"getAmount": document.getElementById('amount').value
});
}
{user.username} you can be seen inside tags...
function GetAmount(){
socket.emit('getAmount', {
"username": "JohnDoe",
"maxBalance": "3750",
"getAmount": document.getElementById('amount').value
});
}
I'm sure there is a better more safer way of identifying which user pressed the Button... Hope someone can explain the best way I could achieve it with Socket.IO, just started using it and I find it to be a lot better than Ajax in many ways but currently lack basic understanding of it's methodology and even Mongo for that matter :))
Thank you for your help ! Kudos !!!

Take a look into socketio-jwt (https://github.com/auth0/socketio-jwt) I think it's what you're after. Basically you need authentication for the active users.

Related

Strapi & react-admin : I'd like to set 'Content-Range' header dynamically when any fetchAll query fires

I'm still a novice web developer, so please bear with me if I miss something fundamental !
I'm creating a backoffice for a Strapi backend, using react-admin.
React-admin library uses a 'data provider' to link itself with an API. Luckily someone already wrote a data provider for Strapi. I had no problem with step 1 and 2 of this README, and I can authenticate to Strapi within my React app.
I now want to fetch and display my Strapi data, starting with Users. In order to do that, quoting Step 3 of this readme : 'In controllers I need to set the Content-Range header with the total number of results to build the pagination'.
So far I tried to do this in my User controller, with no success.
What I try to achieve:
First, I'd like it to simply work with the ctx.set('Content-Range', ...) hard-coded in the controller like aforementioned Step 3.
Second, I've thought it would be very dirty to c/p this logic in every controller (not to mention in any future controllers), instead of having some callback function dynamically appending the Content-Range header to any fetchAll request. Ultimately that's what I aim for, because with ~40 Strapi objects to administrate already and plenty more to come, it has to scale.
Technical infos
node -v: 11.13.0
npm -v: 6.7.0
strapi version: 3.0.0-alpha.25.2
uname -r output: Linux 4.14.106-97.85.amzn2.x86_64
DB: mySQL v2.16
So far I've tried accessing the count() method of User model like aforementioned step3, but my controller doesn't look like the example as I'm working with users-permissions plugin.
This is the action I've tried to edit (located in project/plugins/users-permissions/controllers/User.js)
find: async (ctx) => {
let data = await strapi.plugins['users-permissions'].services.user.fetchAll(ctx.query);
data.reduce((acc, user) => {
acc.push(_.omit(user.toJSON ? user.toJSON() : user, ['password', 'resetPasswordToken']));
return acc;
}, []);
// Send 200 `ok`
ctx.send(data);
},
From what I've gathered on Strapi documentation (here and also here), context is a sort of wrapper object. I only worked with Express-generated APIs before, so I understood this snippet as 'use fetchAll method of the User model object, with ctx.query as an argument', but I had no luck logging this ctx.query. And as I can't log stuff, I'm kinda blocked.
In my exploration, I naively tried to log the full ctx object and work from there:
// Send 200 `ok`
ctx.send(data);
strapi.log.info(ctx.query, ' were query');
strapi.log.info(ctx.request, 'were request');
strapi.log.info(ctx.response, 'were response');
strapi.log.info(ctx.res, 'were res');
strapi.log.info(ctx.req, 'were req');
strapi.log.info(ctx, 'is full context')
},
Unfortunately, I fear I miss something obvious, as it gives me no input at all. Making a fetchAll request from my React app with these console.logs print this in my terminal:
[2019-09-19T12:43:03.409Z] info were query
[2019-09-19T12:43:03.410Z] info were request
[2019-09-19T12:43:03.418Z] info were response
[2019-09-19T12:43:03.419Z] info were res
[2019-09-19T12:43:03.419Z] info were req
[2019-09-19T12:43:03.419Z] info is full context
[2019-09-19T12:43:03.435Z] debug GET /users?_sort=id:DESC&_start=0&_limit=10& (74 ms)
While in my frontend I get the good ol' The Content-Range header is missing in the HTTP Response message I'm trying to solve.
After writing this wall of text I realize the logging issue is separated from my original problem, but if I was able to at least log ctx properly, maybe I'd be able to find the solution myself.
Trying to summarize:
Actual problem is, how do I set my Content-Range properly in my strapi controller ? (partially answered cf. edit 3)
Collateral problem n°1: Can't even log ctx object (cf. edit 2)
Collateral problem n°2: Once I figure out the actual problem, is it feasible to address it dynamically (basically some callback function for index/fetchAll routes, in which the model is a variable, on which I'd call the appropriate count() method, and finally append the result to my response header)? I'm not asking for the code here, just if you think it's feasible and/or know a more elegant way.
Thank you for reading through and excuse me if it was confuse; I wasn't sure which infos would be relevant, so I thought the more the better.
/edit1: forgot to mention, in my controller I also tried to log strapi.plugins['users-permissions'].services.user object to see if it actually has a count() method but got no luck with that either. Also tried the original snippet (Step 3 of aforementioned README), but failed as expected as afaik I don't see the User model being imported anywhere (the only import in User.js being lodash)
/edit2: About the logs, my bad, I just misunderstood the documentation. I now do:
ctx.send(data);
strapi.log.info('ctx should be : ', {ctx});
strapi.log.info('ctx.req = ', {...ctx.req});
strapi.log.info('ctx.res = ', {...ctx.res});
strapi.log.info('ctx.request = ', {...ctx.request});
ctrapi.log.info('ctx.response = ', {...ctx.response});
Ctx logs this way; also it seems that it needs the spread operator to display nested objects ({ctx.req} crash the server, {...ctx.req} is okay). Cool, because it narrows the question to what's interesting.
/edit3: As expected, having logs helps big time. I've managed to display my users (although in the dirty way). Couldn't find any count() method, but watching the data object that is passed to ctx.send(), it's equivalent to your typical 'res.data' i.e a pure JSON with my user list. So a simple .length did the trick:
let data = await strapi.plugins['users-permissions'].services.user.fetchAll(ctx.query);
data.reduce((acc, user) => {
acc.push(_.omit(user.toJSON ? user.toJSON() : user, ['password', 'resetPasswordToken']));
return acc;
}, []);
ctx.set('Content-Range', data.length) // <-- it did the trick
// Send 200 `ok`
ctx.send(data);
Now starting to work on the hard part: the dynamic callback function that will do that for any index/fetchAll call. Will update once I figure it out
I'm using React Admin and Strapi together and installed ra-strapi-provider.
A little boring to paste Content-Range header into all of my controllers, so I searched for a better solution. Then I've found middleware concept and created one that fits my needs. It's probably not the best solution, but do its job well:
const _ = require("lodash");
module.exports = strapi => {
return {
// can also be async
initialize() {
strapi.app.use(async (ctx, next) => {
await next();
if (_.isArray(ctx.response.body))
ctx.set("Content-Range", ctx.response.body.length);
});
}
};
};
I hope it helps
For people still landing on this page:
Strapi has been updated from #alpha to #beta. Care, as some of the code in my OP is no longer valid; also some of their documentation is not up to date.
I failed to find a "clever" way to solve this problem; in the end I copy/pasted the ctx.set('Content-Range', data.length) bit in all relevant controllers and it just worked.
If somebody comes with a clever solution for that problem I'll happily accept his answer. With the current Strapi version I don't think it's doable with policies or lifecycle callbacks.
The "quick & easy fix" is still to customize each relevant Strapi controller.
With strapi#beta you don't have direct access to controller's code: you'll first need to "rewrite" one with the help of this doc. Then add the ctx.set('Content-Range', data.length) bit. Test it properly with RA, so for the other controllers, you'll just have to create the folder, name the file, copy/paste your code + "Search & Replace" on model name.
The "longer & cleaner fix" would be to dive into the react-admin source code and refactorize so the lack of "Content-Range" header doesn't break pagination.
You'll now have to maintain your own react-admin fork, so make sure you're already committed into this library and have A LOT of tables to manage through it (so much that customizing every Strapi controller will be too tedious).
Before forking RA, please remember all the stuff you can do with the Strapi backoffice alone (including embedding your custom React app into it) and ensure it will be worth the trouble.

Discord <#!userid> vs <#userid>

so I'm creating a bot using Node.JS / Discord.JS and I have a question.
On some servers, when you mention a user, it returns in the console as <#!userid> and on other it returns as <#userid>.
My bot has a simple points / level system, and it saves in a JSON file as <#!userid>, so on some servers when trying to look at a users points by mentioning them will work, and on others it won't.
Does anyone have any idea how to fix this? I've tried to find an answer many times, and I don't want to have it save twice, once as <#!userid> and then <#userid>. If this is the only way to fix it then I understand.
Thanks for your help!
The exclamation mark in the <#!userID> means they have a nickname set in that server. Using it without the exclamation mark is more reliable as it works anywhere. Furthermore, you should save users with their id, not the whole mention (the "<#userid>"). Parse out the extra symbols using regex.
var user = "<#!123456789>" //Just assuming that's their user id.
var userID = user.replace(/[<#!>]/g, '');
Which would give us 123456789. Their user id. Of course, you can easily obtain the user object (you most likely would to get their username) in two ways, if they're in the server where you're using the command, you can just
var member = message.guild.member(userID);
OR if they're not in the server and you still want to access their user object, then;
client.fetchUser(userID)
.then(user => {
//Do some stuff with the user object.
}, rejection => {
//Handle the error in case one happens (that is, it could not find the user.)
});
You can ALSO simply access the member object directly from the tag (if they tagged them in the message).
var member = message.mentions.members.first();
And just like that, without any regex, you can get the full member object and save their id.
var memberID = member.id;

Best practices form processing with Express

I'm writing a website which implements a usermanagement system and I wonder what best practices regarding form processing I have to consider.
Especially performance, security, SEO and user experience are important to me. When I was working on it I came across a couple questions and I didn't find an complete node/express code snippet where I could figure out all of my below questions.
Use case: Someone is going to update the birthday of his profile. Right now I am doing a POST request to the same URL to process the form on that page and the POST request will respond with a 302 redirect to the same URL.
General questions about form processing:
Should I do a POST request + 302 redirect for form processing or rather something else like an AJAX request?
How should I handle invalid FORM requests (for example invalid login, or email address is already in use during signup)?
Express specific questions about form processing:
I assume before inserting anything into my DB I need to sanitize and validate all form fields on the server side. How would you do that?
I read some things about CSRF but I have never implemented a CSRF protection. I'd be happy to see that in the code snippet too
Do I need to take care of any other possible vulnerabilities when processing forms with Express?
Example HTML/Pug:
form#profile(method='POST', action='/settings/profile')
input#profile-real-name.validate(type='text', name='profileRealName', value=profile.name)
label(for='profile-real-name') Name
textarea#profile-bio.materialize-textarea(placeholder='Tell a little about yourself', name='profileBio')
| #{profile.bio}
label(for='profile-bio') About
input#profile-url.validate(type='url', name='profileUrl', value=profile.bio)
label(for='profile-url') URL
input#profile-location.validate(type='text', name='profileLocation', value=profile.location)
label(for='profile-location') Location
.form-action-buttons.right-align
a.btn.grey(href='' onclick='resetForm()') Reset
button.btn.waves-effect.waves-light(type='submit')
Example Route Handlers:
router.get('/settings/profile', isLoggedIn, profile)
router.post('/settings/profile', isLoggedIn, updateProfile)
function profile(req, res) {
res.render('user/profile', { title: 'Profile', profile: req.user.profile })
}
function updateProfile(req, res) {
var userId = req.user._id
var form = req.body
var profile = {
name: form.profileRealName,
bio: form.profileBio,
url: form.profileUrl,
location: form.profileLocation
}
// Insert into DB
}
Note: A complete code snippet which takes care of all form processing best practices adapted to the given example is highly appreciated. I'm fine with using any publicly available express middleware.
Should I do a POST request + 302 redirect for form processing or rather something else like an AJAX request?
No, best practice for a good user experience since 2004 or so (basically since gmail launched) has been form submission via AJAX and not web 1.0 full-page load form POSTs. In particular, error handling via AJAX is less likely to leave your user at a dead end browser error page and then hit issues with the back button. The AJAX in this case should send an HTTP PATCH request to be most semantically correct but POST or PUT will also get the job done.
How should I handle invalid FORM requests (for example invalid login, or email address is already in use during signup)?
Invalid user input should result in an HTTP 400 Bad Request status code response, with details about the specific error(s) in a JSON response body (the format varies per application but either a general message or field-by-field errors are common themes)
For email already in use I use the HTTP 409 Conflict status code as a more particular flavor of general bad request payload.
I assume before inserting anything into my DB I need to sanitize and validate all form fields on the server side. How would you do that?
Absolutely. There are many tools. I generally define a schema for a valid request in JSON Schema and use a library from npm to validate that such as is-my-json-valid or ajv. In particular, I recommend being as strict as possible: reject incorrect types, or coerce types if you must, remove unexpected properties, use small but reasonable string length limits and strict regular expression patterns for strings when you can, and of course make sure your DB library property prevents injection attacks.
I read some things about CSRF but I have never implemented a CSRF protection.
The OWSAP Node Goat Project CSRF Exercise is a good place to start with a vulnerable app, understand and exploit the vulnerability, then implement the fix (in this case with a straightforward integration of the express.csrf() middleware.
Do I need to take care of any other possible vulnerabilities when processing forms with Express?
Yes generally application developers must understand and actively code securely. There's a lot of material out there on this but particular care must be taken when user input gets involved in database queries, subprocess spawning, or being written back out to HTML. Solid query libraries and template engines will handle most of the work here, you just need to be aware of the mechanics and potential places malicious user input could sneak in (like image filenames, etc).
I am certainly no Express expert but I think I can answer at least #1:
You should follow the Post/Redirect/Get web development pattern in order to prevent duplicate form submissions. I've heard a 303-redirect is the proper http statuscode for redirecting form submissions.
I do process forms using the POST route and once I'm done I trigger a 302-redirect.
As of #3 I recommend looking into express-validator, which is well introduce here: https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/forms . It's a middleware which allows you to validate and sanitize like this:
req.checkBody('name', 'Invalid name').isAlpha();
req.checkBody('age', 'Invalid age').notEmpty().isInt();
req.sanitizeBody('name').escape();
I wasn't able to comment hence the answer even though it's not a complete answer. Just thought it might help you.
If user experience is something you're thinking about, a page redirection is a strong no. Providing a smooth flow for the people visiting your website is important to prevent drops, and since forms are already not such a pleasure to fill, easing their usage is primary. You don't want to reload their page that might have already took some time to load just to display an error message. Once the form is valid and you created the user cookie, a redirection is fine though, even if you could do things on the client app to prevent it, but that's out-of-scope.
As stated by Levent, you should checkout express-validator, which is the more established solution for this kind of purpose.
req.check('profileRealName', 'Bad name provided').notEmpty().isAlpha()
req.check('profileLocation', 'Invalid location').optional().isAlpha();
req.getValidationResult().then(function (result) {
if (result.isEmpty()) { return null }
var errors = result.array()
// [
// { param: "profileRealName", msg: "Bad name provided", value: ".." },
// { param: "profileLocation", msg: "Invalid location", value: ".." }
// ]
res.status(400).send(errors)
})
.then(function () {
// everything is fine! insert into the DB and respond..
})
From what it looks like, I can assume you are using MongoDB. Given that, I would recommend using an ODM, like Mongoose. It will allow you to define models for your schemas and put restrictions directly on it, letting the model handles these kind of redundant validations for you.
For example, a model for your user could be
var User = new Schema({
name: { type: String, required: [true, 'Name required'] },
bio: { type: String, match: /[a-z]/ },
age: { type: Number, min: 18 }, // I don't know the kind of site you run ;)
})
Using this schema on your route would be looking like
var user = new User({
name: form.profileRealName,
bio: form.profileBio,
url: form.profileUrl,
location: form.profileLocation
})
user.save(function (err) {
// and you could grab the error here if it exists, and react accordingly
});
As you can see it provides a pretty cool api, which you should read about in their docs if you want to know more.
About CRSF, you should install csurf, which has pretty good instructions and example usages on their readme.
After that you're pretty much good to go, there is not much more I can think about apart making sure you stay up to date with your critical dependencies, in case a 0-day occurs, for example the one that happened in 2015 with JWTs, but that's still kinda rare.

Video Panel doesn't get dismissed when other user hangs call

I've just added vline to my php5/jQuery portal.
Everything seems to work good but a thing that's driving me mad.
Suppose to have two users calling one each other via vline. User1 calls User2, User2 answers, after some time User2 hangs up the call. User1 still sees the Video Panel and he cannot dismiss it.
This happens also il User2 declines the call, User1 sees the Video Panel.
Can someone help me address this issue?
Thanks
I finally managed to make it work by doing the following:
Added a video-wrapper <div> to my html
Created the vline client by passing in this option "uiVideoPanel": "video-wrapper"
handled the following events
enterState:incoming
enterState:outgoing
enterState:closed
as follows:
client = vline.Client.create({
"serviceId": serviceId,
"ui": true,
"uiVideoPanel": "video-wrapper"
});
client.on('enterState:incoming', handleShowWrapper).
on('enterState:outgoing', handleShowWrapper).
on('enterState:closed', handleHideWrapper);
function handleShowWrapper(event) {
$("#video-wrapper").show();
}
function handleHideWrapper(event) {
$("#video-wrapper").html("");
$("#video-wrapper").hide();
}
Obviously it's a workaround but at least it make the call flow work properly.
Let me know if someone has a more elegant solution or if vline manage to solve it and the workaround is no more needed.
Thanks

Resolve MongoDB reference

I am currently building a chatting app with nodejs and mongoDB.
Basically I have two collections to maintain in the db.
user = {
_id: ObjectId("1234"),
account: "stan123"
}
thread = {
_user: ObjectId("1234"),
messages: [
{
body:"hi"
_user:ObjectId("1234")
},
{
body:"second msg"
_user:ObjectId("1234")
}
]
}
I am planning to pass the thread model with all resolved info (user) to the client side, so that I can construct my widget with it.
I searched for solutions for this.Some suggests to make extra calls from client side to get the data.
However, I am worried that when the amount of message grows, there will be considerable http calls that might hurt site speed.
I know some drivers can resolve DBRefs automatically and make the code clean.
However, according to
http://docs.mongodb.org/manual/applications/database-references/
I decided to just use id to maintain reference that make it's as simple as possible.
My plan is resolving all references on server side. Current approach is getting the length of message array first.
Then loop through the message array and make a second query to resolve user info separately.
In each query callback, do a messageToResolve++ and if(messageToResolve >= thread.messages.length)
If the condition meets, send the resolved model to client and end the response.
This is not a case I would consider embedded because it would be painful when you need to update user data.
(message is embedded because it exists only when thread exists)
I am not sure if it's a good way to do it.
Does anyone has a better solution?
Sorry if I didn't explain my problem and solution clear enough.
And thanks in advance.

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