I started by using express-form with my api (Express 3.3.8) in order to trim leading and trailing whitespace off of incoming POSTed fields.
However, I believe to use it I must include the form fields and rules in my middleware to my routes like so:
app.post('/api/test', form(
field("username").trim(),
field("password").trim(), function(req, res...
My question is, is there a way to do the trim automatically without specifying the fields individually? I know of the configuration option: autoTrim, but I think I still need to specify the fields on a per route/middleware basis, right? I tried leaving it out of the middleware, and just doing the form.configure({autoTrim:true}), but nothing changed with the req.body fields. Same as if I never included express-form at all.
I'm not committed to express-form. If there's another way already available to have Express always trim incoming req.body fields, please let me know.
app.use(postTrimmer);
function postTrimmer(req, res, next) {
if (req.method === 'POST') {
for (const [key, value] of Object.entries(req.body)) {
if (typeof(value) === 'string')
req.body[key] = value.trim();
}
}
next();
}
Don't forget to turn on the "body-parser" module before using postTrimmer middleware.
As it seems one must declare the fields individually using express-form, I decided to write my own whitespace trimming middleware for now as I couldn't find an existing simple solution. I use underscore.js, so you'll see its map function in use. You could otherwise do your own looping with the native Object.keys or similar. This completely rewrites all fields in req.body! Please note, this is a stop-gap for a greater validation issue. We're just doing this temporarily until we have time to clean up validation as a whole. Here's my code (put before app.use(app.router) of course):
var trimmer = function(req, res, next){
req.body = _.object(_.map(req.body, function (value, key) {
return [key, value.trim()];
}));
next();
}
app.use(trimmer);
I created a npm module for the very purpose. It provides you 4 middlewares that you can use to trim req.body, req.query, req.params or all three. It also provides a separate utility which you can use to trim any object.
This module works recursively so doesn't matter how nested the string is in object, It will be trimmed.
request_trimmer
npm i request_trimmer
const express = require('express');
const app = express();
const { trim_all,trim_body,trim_params,trim_util } = require('request_trimmer');
app.use(express.json());
#trim request body and query.
app.use(trim_all)
Related
Hello i am creating a validation middleware but the problem is i have 2 types to the same endpoint so i created two schema for each.
All i want to do is when type is somthing pass through middleware_a esle return middleware_b
here is my idea but its not working
const middlewareStrategy = (req,res,next) => {
if(req.params.type === "Something"){
return custom_middleware(schemas.A_body);
}
return custom_middleware(schemas.B_body);};
A_Body here is just validation schema.
It's a bit hard to tell eactly what you're trying to do because you don't show the actual middleware code, but you can dynamically select a middleware a couple of different ways.
Dynamically call the desired processing function
const middlewareStrategy = (req,res,next) => {
const schema = req.params.type === "Something" ? schemas.A_body : schemas.B_body;
bodyStrategy(schema, req, res, next);
};
In this middleware, you're dynamically calling a bodyStrategy function that takes the schema and res, res, next so it can act as middleware, but will know the schema.
Create a middleware that sets the schema on the req object
const middlewareStrategy = (req,res,next) => {
req.schema = req.params.type === "Something" ? schemas.A_body : schemas.B_body;
next();
};
Then, use it like this:
// this sets req.schema to be used by later middleware
app.use(middlewareStrategy);
Then, you can use another middleware that expects to find the req.schema property to do its job:
// this middleware uses req.schema
app.use(customMiddleware);
If this isn't exactly what you were looking for, then please include the code of your actual middleware so we can see what we're really aiming for.
Does any one knows an example or could explain here how node.js and express would have to route for a multilanguage site? I'm using i18n-node for translation and folder like routing ( /es/, /de/ , etc ) for different languages. This all are static routes but I also have routes like apiRoutes.route('/user/profile') using 'app' at the begining ( app.get('/app/user/profile') so please consider this in your answer so is NOT necesary route to : app.get('/es/app/user/profile') .
having 15 routes like this now:
app.get('/terms', function(req, res) {
res.render('terms',{
...
});
});
how it have to be set for routes like:
app.get('/es/terms', function(req, res) {
res.render('terms',{
...
});
});
Should I duplicate this routes and add for example a locale for
each like:
app.get('/es/terms', function(req, res) {
res.render('terms',{
...
});
});
Or Should do something like:
if cookie['lang'] && cookie['lang'] is in locales
// then redirect to /:lang/terms
else
// show default language in /terms
if req.headers["accept-language"] && req.headers["accept-language"]
// then redirect to /:lang/terms
else
//show default language in /terms
Or there is another way I should approach this that follows good practices or is better respecting standards?
Miro's Answer in :
How can I get the browser language in node.js (express.js)? says I should use app.all('*', ...
Is this all I need?, ..still, it might have a syntax error or i'm not understanding well this two parts
var rxLocal = /^\/(de|en)/i;
...
app.get(/\/(de|en)\/login/i, routes.login);
thanks in advance
You need to consider 2 things :
1. How get the local :
Accept-Language
The HTTP protocole define the Accept-Language header to manage the local. This is a normalized method. You can access it with the req.acceptsLanguages method of express.
+Normalized
+Natively support by brower
-Not easy to by passe by the end user
Path / Cookies
You can get the local from the path. In express it can be do with a parameter patter like /:local/rest/of/path and retrieve in the request object with the req.param method.
You can also get the information from the cookies with the req.cookies properties (don't forgot to set it).
Both
To increase the user experience you can mix the both method. For exemple get the default language from the HTTP header send by the browser but permite to the user to override this in you application and store this parameter in the cookies.
2. Use the local:
Each methods to get the local can be used from different way. I will
use random of them in exemple but they are all compatible.
Top level configuration.
In case of you use a template Engine and you controller can be local agnostic. You can use a middleware to get the local information and configure the render engine.
app.use('/:local' (req, res, next) => {
let localKey = req.param('local');
res.locals = // Some ingenious method to get the locales from localKey
next();
}
Check res.locals and your engine documentation.
Use it in controller.
If the local is part of the contoller process. You can get directly is value in controller.
In case of you use a complexe method to determine the final value of the local, you can also use a middleware to determine this value and enrich the request with it.
app.use((req, res, next) => {
let local = req.cookies.local;
if(!local) local = req.acceptsLanguages();
if(!local) local = 'en-US';
req.local = local;
}
Both
You can use both method too. It depend of what you need. Find the best way to get a maintainable code and avoid replication for your use case.
When you use middle where witch impact the controllers, be sure you declare them before your routes.
You can use a route parameter to get the locale from the URL, like this:
app.get('/:lang/terms', function (req, res) {
if (req.params === 'es') {
res.send('¡Hola!');
else {
res.send('Hi!');
}
});
The colon character tells Express to put whatever is between the first to slashes of the path in req.params.lang.
See express routing documentation for details.
In my express application I have a module called helpers thats is required in almost all my routes and modules. This module has a logger method that logs to fluentd (but that's unimportant). While building the data to log I'd like to add a unique identifier of the request, so that all the logs written for the same request have the same unique ID. Using a global var in the app entry point app.use doesn't work because this var would be overwritten every time a new request hits, so the global uuid will change would obviously change in case of high load or long running tasks. The res.locals is not available outside routing, so I can't use it for this matter. Is there a way to create a var that would be unique per request and available in every module or maybe a way to access the res.locals data outside routing? Thank you
EDIT
Maybe an example will help understand better the question.
Suppose I have a module called helpers.js like this:
let helpers = {};
helpers.log = (logData, logName) => {
fluentLogger.emit('', {
name: logName,
//uuid: the needed uuid,
message: logData
});
}
module.exports = helpers;
Now obviously I can do this in my app.js entry point:
app.use(function (req, res, next) {
res.locals.uuid = uuid.v4();
next();
});
and then in every loaded middleware module that requires helpers(adding a new param to the helpers.log method):
const helpers = require('helpers');
router.post('/', (req, res, next) => {
helpers.log('my log message', 'myLogName', res.locals.uuid);
next();
});
and this will normally work. But suppose a big or middle size project where there are hundreds of custom modules and models (not middlewares) and a module may require other modules that require other modules that require finally the helpers module. In this case I should pass the res.locals.uuid as a parameter to every method of every method so that I have it available in the logger method. Not a very good idea. Suppose I have a new module called dbmodel.js that is required in a middleware function:
const helpers = require('helpers');
let dbmodel = {};
dbmodel.getSomeData = (someParam) => {
//some logic
helpers.log('my log message', 'myLogName');
}
module.exports = dbmodel;
The dbmodel has no idea about the res.locals data if I don't pass it from the middleware, so the helpers.log method will also have no idea about this.
In PHP one would normally write a GLOBAL var in the application's entry point so a hypothetical logger function would have access to this global on every method request from whichever class of the application.
Hope this explanation will help :) Thank you
EDIT 2
The solution for this kind of problems is CLS. Thanks to #robertklep for the hint. A good slideshare explaining exactly the same problem (logger with unique ID) and explaining the CLS solutions can be found here: https://www.slideshare.net/isharabash/cls-and-asynclistener
I answered a very similar question here which will solve this problem.
I used to solve the problem the libraries node-uuid and continuation-local-storage. Take a look to the answer of this question and see if it helps:
NodeJS Express - Global Unique Request Id
And you want a bigger explanation, take a look here:
Express.js: Logging info with global unique request ID – Node.js
Yes you can do so by one method .
Every request comes to his routes pass that request inside the middleware.
Suppose you have
app.get('/', function(req, res) {
res.sendFile(path.join(public + "index.html"));
});
a request.
Place Middleware in it .and edit req field coming , in this way you will get the unique variable values for each request
check out this .
https://expressjs.com/en/guide/writing-middleware.html
Like this
var requestTime = function (req, res, next) {
req.requestTime = Date.now()
next()
}
app.use(requestTime)
app.get('/', function (req, res) {
var responseText = 'Hello World!<br>'
responseText += '<small>Requested at: ' + req.requestTime + '</small>'
res.send(responseText)
})
Here req.requestTime is unique for each request.
I am using node express to process POST requests of heroku logging data with body data that is in the application/logplex-1 format (apparently syslog formatted).
In particular, I am using the body-parser module as middleware to parse the POST body.
It works OK to specify app.use(bodyParser.text({ type: 'application/logplex-1' })) to force body-parser to parse the body as text, but the text is just a big block of space-separated information without much structure other than that. Therefore I need to parse the body data further to find and extract what I want.
This is OK, but I'm wondering if there is, perhaps, a better way of parsing the logplex-1 body more directly into something more structured and easier to work with, like JSON. I'm not familiar with logplex-1 or the syslog format, and whether it does indeed have anything more useful structure/metadata in it than is apparent from the text block I'm currently getting.
Any ideas?
I have no experience with logplex or Heroku, but this seems to be working:
var syslogParser = require('glossy').Parse;
var express = require('express');
var app = express();
var server = app.listen(3012);
// Express allows arrays-of-middleware to act as a "single" middleware.
var logplexMiddleware = [
// First, read the message body into `req.body`, making sure it only
// accepts logplex "documents".
require('body-parser').text({ type: 'application/logplex-1' }),
// Next, split `req.body` into separate lines and parse each one using
// the `glossy` syslog parser.
function(req, res, next) {
req.body = (req.body || '').split(/\r*\n/).filter(function(line) {
// Make sure we only parse lines that aren't empty.
return line.length !== 0;
}).map(function(line) {
// glossy doesn't like octet counts to be prepended to the log lines,
// so remove those.
return syslogParser.parse(line.replace(/^\d+\s+/, ''));
});
next();
}
];
// Example endpoint:
app.post('/', logplexMiddleware, function(req, res) {
console.log(req.body);
return res.sendStatus(200);
});
It uses glossy to parse the syslog messages into Javascript objects.
If the amount of data being posted is considerable (>hundreds of K's), it might be better to implement a streaming solution as the code above will first read the entire message body into memory.
I am trying to have a variable which can be accessible by all controllers in my node project. Currently in one controller I have:
var ua = req.headers['user-agent'];
var isMobile = "no";
if(/mobile/i.test(ua))
isMobile="yes";
It's pointless to copy past all of this for all my controllers and pass the isMobile variable to the view. I'd like to get the value of isMobile set once, and then pass it wherever I want from my controllers.
Is there an easy way to do this rather than have those 4 lines of code copy pasted in every controller?
Thanks
You'll want to use a Sails policy for this:
// /api/policies/isMobile.js
module.exports = function(req, res, next) {
var ua = req.headers['user-agent'];
req.isMobile = /mobile/i.test(ua);
next();
}
// /config/policies.js
module.exports.policies = {
'*': 'isMobile'
};
This will run the code before every controller action, and give you access to the req.isMobile var in all of your custom controller code.
A truly global variable isn't particularly an option as any concurrency above 1 will likely result in unexpected behavior. Being that it is something particular to the unique request itself, the req object is likely your best bet.
Assuming you have access to the req object everywhere that you would like to utilize use this flag, you can simply add a property to the req object at any point (preferably early in the request/response cycle). After this property is added, it should be available everywhere that has access to req.
req.isMobile = /mobile/i.test(req.headers['user-agent']) ? 'yes' : 'no';
Or if there is a concept like middleware in express for sails
function isMobile(req, res, next) {
req.isMobile = /mobile/i.test(req.headers['user-agent']) ? 'yes' : 'no';
next();
}