per-request session in meteor server? - node.js

I am adding an auth layer and I think I have it figured out except for one tricky detail.
My Meteor app doesn't have any routes but I've added a hook into the connect middleware so that the "/" route errors if there isn't a correct API token. If the token is okay then I call next() to forward the route to Meteor.
The problem is that, depending on the token, I need to set server-side parameters for the connection, and I don't know how to do this. For example, say I have a static list of API keys mapped to permission levels. If a user sends a request with "ADMIN_API_KEY" then I would like to set Session.permission_level = "admin" for use by the Meteor server's functions. Session is just for the client in Meteor, though.
# this code's in coffeescript
WebApp.connectHandlers.use '/', (req, res, next) ->
validator = new RequestValidator(req, next)
validations = [
"valid_namespace",
"only_https"
]
error = validator.validate(validations)
next(error)
# <<<<<<<<<<<<<<<<<<<<<<<<
# Here I want to set some config option which can be
# read by the server in the same way it can read things like
# Meteor.user()
In Rails I would just say session[:permission_level] = "admin". But it seems to not work this way in Meteor.
By the way, I am not using a Routing package yet in Meteor, though if that would make this easier than I would.

I'm not sure about Session I've been doing something like
import { DDP } from 'meteor/ddp';
import { DDPCommon } from 'meteor/ddp-common';
export const authMiddleware = (req, res, next) => {
const userId = identifyUser(req); // parse the request to get the token you expect
if (!userId) {
return next();
}
DDP._CurrentInvocation.withValue(new DDPCommon.MethodInvocation({
isSimulation: false,
userId,
}), () => {
next();
// in that context, Meteor.userId corresponds to userId
});
};
for my REST api and that works well regarding the user Id and being able to call Meteor function that should be invoke in a DDP context, like Users.find(...).

Related

How to use only PART of the functionality in nested routes NodeJS

So I have a router schoolsRouter where all the school-specific functionality is being handled { login school, adding a new teacher, ...etc.). And I want the admin of the app to be able to add and delete new schools. Now the pattern I'm using encapsulates all the routing functionality in one file schools.routes.js where the School model is exposed. So the createSchool and deleteSchool routes are in the schools.routes.js but I need only the admin to be able to perform those operations and that seems pretty easy with merged routes like this (in admins.routes.js):
adminsRouter.use('/schools/', schoolsRouter);
but the problem is that now the admin can access all the other routes in schools.routes.js like schools/login which is something that I don't want to happen. So how can I make the adminsRouter use the create and delete operations from the schoolsRotuer without being able to access all these other functionalities? (Keeping in mind I'm using JWT authentication).
You could use middlewares in the routes that you wish to controll.
This is the middleware that I will name of admin-middleware.js
module.exports = (req, res, next) => {
if (user.admin === true) {
return next();
} else {
return res.status(403).send('Unauthorized')
}
}
So, this is your route declaration at schools.routes.js
const adminMiddleware = require('../YOUR_FOLDERS/admin-middleware.js');
schools.delete('/:id', adminMiddleware, (req, res) => {
return res.send('ok');
});
If you wish disregard a route, you can use this validation at your code in the middleware.
if(req.originalUrl.includes('/schools/login'))
return next();
I hope that it works to you.

How to remove authentication for introspection query in Graphql

so may be this is very basic question so please bear with me. Let me explain what I am doing and what I really need.
EXPLANATION
I have created a graphql server by using ApolloGraphql (apollo-server-express npm module).
Here is the code snippet to give you an idea.
api.js
import express from 'express'
import rootSchema from './root-schema'
.... // some extra code
app = express.router()
app.use(jwtaAuthenticator) // --> this code authenticates Authorization header
.... // some more middleware's added
const graphQLServer = new ApolloServer({
schema: rootSchema, // --> this is root schema object
context: context => context,
introspection: true,
})
graphQLServer.applyMiddleware({ app, path: '/graphql' })
server.js
import http from 'http'
import express from 'express'
import apiRouter from './api' // --> the above file
const app = express()
app.use([some middlewares])
app.use('/', apiRouter)
....
....
export async function init () {
try {
const httpServer = http.createServer(app)
httpServer
.listen(PORT)
.on('error', (err) => { setTimeout(() => process.exit(1), 5000) })
} catch (err) {
setTimeout(() => process.exit(1), 5000)
}
console.log('Server started --- ', PORT)
}
export default app
index.js
require('babel-core')
require('babel-polyfill')
require = require('esm')(module/* , options */)
const server = require('./server.js') // --> the above file
server.init()
PROBLEM STATEMENT
I am using node index.js to start the app. So, the app is expecting Authorization header (JWT token) to be present all the times, even for the introspection query. But this is not what I want, I want that introspection query will be resolvable even without the token. So that anyone can see the documentation.
Please shed some light and please guide what is the best approach to do so. Happy coding :)
.startsWith('query Introspection') is insecure because any query can be named Introspection.
The better approach is to check the whole query.
First import graphql and prepare introspection query string:
const { parse, print, getIntrospectionQuery } = require('graphql');
// format introspection query same way as apollo tooling do
const introspectionQuery = print(parse(getIntrospectionQuery()));
Then in Apollo Server configuration check query:
context: ({ req }) => {
// allow introspection query
if (req.body.query === introspectionQuery) {
return {};
}
// continue
}
There's a ton of different ways to handle authorization in GraphQL, as illustrated in the docs:
Adding middleware for express (or some other framework like hapi or koa)
Checking for authorization inside individual resolvers
Checking for authorization inside your data models
Utilizing custom directives
Adding express middleware is great for preventing unauthorized access to your entire schema. If you want to allow unauthenticated access to some fields but not others, it's generally recommended you move your authorization logic from the framework layer to the GraphQL or data model layer using one of the methods above.
So finally I found the solution and here is what I did.
Let me first tell you that there were 2 middle-wares added on base path. Like this:
app //--> this is express.Router()
.use(jwtMw) // ---> these are middlewares
.use(otherMw)
The jwtMw is the one that checks the authentication of the user, and since even introspection query comes under this MW, it used to authenticate that as well. So, after some research I found this solution:
jwtMw.js
function addJWTMeta (req, res, next) {
// we can check for null OR undefined and all, then check for query Introspection, with better condition like with ignore case
if (req.body.query.trim().startsWith('query Introspection')) {
req.isIntrospection = true
return next()
}
...
...
// ---> extra code to do authentication of the USER based on the Authorization header
}
export default addJWTMeta
otherMw.js
function otherMw (req, res, next) {
if (req.isIntrospection) return next()
...
...
// ---> extra code to do some other context creation
}
export default otherMw
So here in jwtMw.js we are checking that if the query is Introspection just add a variable in req object and move forward, and in next middleware after the jwtMw.js whosoever wants to check for introspection query just check for that variable (isIntrospection, in this case) and if it is present and is true, please move on. We can add this code and scale to every middleware that if req.isIntrospection is there just carry on or do the actual processing otherwise.
Happy coding :)

Node Express auth status

I have multiple routes, split into different files (my app consists of different "modules", which I maintain in separate folders. For each folder, there is an index.js file in which I manage the routes per module, and I require these in the app.js file).
For every route, I will require to check the auth, and pass the loggedIn status to the header of every page:
//Default variables for the ejs template
var options = {
loggedIn: true
};
res.render("home/home", options);
If the logged in status is true, then the user's name will be displayed. If not, the login / signup labels are displayed.
What is the best way to centralise this, so that I don't need to require the auth script in every of these index.js (route) files?
I need to be able to pass the auth status to the view via the options object (see example).
In your auth, module, use a middleware function. That function can check and store res.locals.loggedIn which will be available for any view that will eventually be rendered. Just make sure the app.use call executes prior to your other routes and it will work properly.
app.use(function auth(req, res, next) {
res.locals.loggedIn = true; // compute proper value here
next();
});
From what I understand you need to do this for every request.One common thing is adding this as middleware so that all the request gets this .
For Example :
var http = require('http');
var connect = require('connect');
var app = connect();
app.use(function(req, res) {
res.end('Hello!');
});
http.createServer(app).listen(3000)
Now for every request , Hello is printed . You could extract this as a module and reuse it across projects. Check here for more details

Unable to register Express middleware

I'm trying to write a very basic piece of middleware for Express that checks to see if a user has some specified role required to access a resource. I have another piece of middleware that comes before this, which adds a user object to the request req for every route requiring authentication (and subsequent authorization).
As such, I define the authorization middleware like this:
_ = require('lodash');
function authorize(req, res, next, roles){
// check to see if user has one of the allowed roles
if(_.contains(roles, req.user.role)){
req.authorized = true;
return next();
}
// otherwise, pass an error
return next(new Error("Unauthorized"));
}
Every user object has a property called role on it, so I use _.contains(roles, req.user.role) to figure out whether or not the allowed roles contain the user's assigned role.
However, when I do this, I get TypeError: Cannot read property 'role' of undefined as soon as I start my Express server. This seems very weird to me, because I have not even made a request, and so of course req.user will be undefined until then.
Is there a way around this?
Example of how I use this middleware:
var app = express();
var router = express.Router();
router.get('/protected/:id', authorize(['ADMINISTRATOR', 'MANAGER', 'OWNER']), controllers.protected.retrieve);
When you register the route with
router.get(
'/protected/:id',
authorize(['ADMINISTRATOR', 'MANAGER', 'OWNER']),
controllers.protected.retrieve
)
the authorize method gets executed straight away by authorize(...) with the ['ADMINISTRATOR', ...] array being passed as the req param. Hence it is called as soon as you run the code and dies on user object not being present. Even if it didn't die on that, it wouldn't work as intended. You are mixing a middleware and a factory function together.
Express middleware is a function with a (req, res, next) signature, that you don't execute yourself. You need to pass a reference to such a middleware function and Express itself executes it on the request when needed, i.e.:
function authorize(req, res, next) {
...
};
router.get('/protected/:id', authorize, ...);
A parametrized middleware function, as in your case, can be easily created by splitting up to a factory and a middleware function:
// a factory function to create authorization middleware functions for given roles
function authorize(roles) {
// create and return an actual authorization middleware function
// to handle requests using the roles given when created
return function(req, res, next) {
if(_.contains(roles, req.user.role)){
req.authorized = true;
return next();
}
return next(new Error("Unauthorized"));
}
}
router.get(
'/protected/:id',
authorize(['ADMINISTRATOR', 'MANAGER', 'OWNER']),
controllers.protected.retrieve
)

NodeJS + Express: How to secure a URL

I am using latest versions of NodeJS and ExpressJS (for MVC).
I usually configure my rest paths like this, for example:
app.get('/archive', routes.archive);
Now i want my /admin/* set of URLs to be secured, I mean I need just simple authentication, it's just a draft.
When a user tries to access, for example, /admin/posts, before sending him the corresponding view and data, I check for a req.session.authenticated. If it's not defined, I redirect to the login page.
Login page has a simple validation form, and a sign-in controller method: if user does send "right user" and "right password" I set the session variable and he's authenticated.
What I find difficult, or I don't understand, is how to actually make the "filter" code, I mean, the auth check, before every /admin/* path call.
Does this have something to do with "middleware" express functions?
Thank you
Yep, middleware is exactly what you want. A middleware function is just a function that works just like any other Express route handler, expept it gets run before your actual route handler. You could, for example, do something like this:
function requireLogin(req, res, next) {
if (req.session.loggedIn) {
next(); // allow the next route to run
} else {
// require the user to log in
res.redirect("/login"); // or render a form, etc.
}
}
// Automatically apply the `requireLogin` middleware to all
// routes starting with `/admin`
app.all("/admin/*", requireLogin, function(req, res, next) {
next(); // if the middleware allowed us to get here,
// just move on to the next route handler
});
app.get("/admin/posts", function(req, res) {
// if we got here, the `app.all` call above has already
// ensured that the user is logged in
});
You could specify requireLogin as a middleware to each of the routes you want to be protected, instead of using the app.all call with /admin/*, but doing it the way I show here ensures that you can't accidentally forget to add it to any page that starts with /admin.
A even simpler approach would be to add the following code in the App.js file.
var auth = function(req, res, next) {
if(isAdmin) {
return next();
} else {
return res.status(400)
}
};
app.use('/admin', auth, apiDecrement);
As you can see the middleware is being attached to the route. Before ExpressJS goes forward, it executes the function that you passed as the second parameter.
With this solution you can make different checks before displaying the site to the end user.
Best.
Like brandon, but you can also go the connect route
app.use('/admin', requireLogin)
app.use(app.router)
app.get('/admin/posts', /* middleware */)

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