I've got a node app using the express server and I'm struggling with the routing. 'Browse' is the function and 'type', 'subtype' and 'name' are variables. If I have a route like:
/browse/type/subtype/name
then I can pick that up with:
/browse/:type/:subtype/:name
...so the vars show up separately in the req.params object. Sometimes, however, not all of the vars will appear, so you may get a url like:
/browse/cars
I want a route that catches them all, but if I use a wildcard then req.params will not pick them up as separate parameters. My best guess was something like:
/browse(/:type)?(/:subtype)?(/:name)?
Anyone know how this should be done?
/browse/:type?/:subtype?/:name? should work
Related
I created a router file using Express. The callback functions reside in their discrete "controllers" files. Following is an excerpt of the parts relevant to my question, and lines such as require of controller functions have been omitted:
const express = require('express');
const router = express.Router();
// This should run first
router.param('coolParamName', validateParamBeforeHandlingReqs);
// Param name is ↑↑↑↑↑ "consumed" here, although NOT defined yet
// This should run after the above code
router.route('/').get(getAllUserNames).post(createUser);
router.route('/:coolParamName').get(getUserName).patch(updateUser).delete(deleteUser);
// Param name is ↑↑↑↑↑ defined here, and was consumed earlier - how?
As the comments explain, it seems like the param name has been defined as coolParamName on the bottom, but "consumed" by the code written above it. This feels strange to me, because I feel it's natural to define first and then use later - is it just me? Did I write a code that's against the intended design pattern?
I would like to understand how Express defines the name of param, and how router.param and router.router handle them.
router.param('coolParamName') essentially registers a callback that will get called for any route (in that router) that uses the :coolParamName parameter and matches the current request. The callback will get called once per request BEFORE the route that matches the request that contains the :coolParamName parameter.
It's kind of like middleware for a matching parameter. It allows you to automatically configure some setup code anytime that particular parameter is matched in a route.
FYI, I expect that router.param() may be one of the least used features of Express since it can be accomplished many other ways, but it probably works best for validation-type code that checks named properties for validity before the route itself gets called.
You could accomplish the same thing by just using a piece of middleware on that specific route too or even just calling a function inside the route handler. So, this is just a nicety feature if you happen to use the same parameter in multiple routes.
I'm trying to create an endpoint that contains an actual path that I extract and use as a parameter. For instance, in the following path:
/myapi/function/this/is/the/path
I want to match "/myapi/function/" to my function, and pass the parameter "this/is/the/path" as the parameter to that function.
If I try this it obviously doesn't work because it only matches the first element of the path:
app.get("/myapi/function/:mypath")
If I try this it works, but it doesn't show up in req.params, I instead have to parse req.path which is messy because the logic has to know about the whole path, not just the parameter:
app.get("/myapi/function/*")
In addition, the use of wildcard routing seems to be discouraged as bad practice. I'm not sure I understand what alternative the linked article is trying to suggest, and I'm not using the query as part of a database call nor am I uploading any information.
What's the proper way to do this?
You can use wildcard
app.get("/myapi/function/*")
And then get your path
req.params[0]
// Example
//
// For the route "/myapi/function/this/is/my/path"
// You will get output "this/is/my/path"
These are the links-
app.get('(/api/v1)?/abcd', abcd.get);
app.post('(/api/v1)?/efgh', efgh.post);
app.get('(/api/v1)?/hijk/:item', hijk.get);
app.get('(/api/v1)?/lmno', lmno.getMulti);
app.delete('(/api/v1)?/pqrs/:item',pqrs.delete);
I want to add app.use() for all the links excluding app.get('(/api/v1)?/abcd', abcd.get);
Express middleware's get executed in the order you define them and therefore, you can simply do something as below to make sure middleware code you want is not executed for specific endpoint:
app.get('(/api/v1)?/abcd', abcd.get);
app.use(<middleware_func>);
app.get('(/api/v1)?/hijk/:item', hijk.get);
app.get('(/api/v1)?/lmno', lmno.getMulti);
app.delete('(/api/v1)?/pqrs/:item',pqrs.delete);
I am using Express with Node and I have a requirement in which the user can request the URL as: http://myhost/api/add?mid="mid01"/userID
and I tried this
app.get('/api/:myMedia/:id', function (req, res){
...
})
and tried these req.query for getting mid01 and it didn't work.
I want to have req.params.id and req.query together. How can I handle this?
If your requirement really is http://myhost/api/add?mid="mid01"/userID, it might be a good idea to change that requirement, because it seems really not the right way to do something
But if you really want to do that you should declare your route like app.get('/api/add', ...)
Then with req.query.mid you can get your query value which is "mid01"/userID
Finaly it's up to you to parse that query value to do what you want
But you should not use URL like that, if possible try to use URL in a more standard way, http://myhost/api/add/userID?mid=mid01 or http://myhost/api/add?mid=mid01&path=/userID
To chain requests, use &. http://myhost/api/add?foo1="bar1"&foo2="bar2". This way both of the queries will show up.
I've read up other questions on people's routes mismatching and then ordering the routes solving the problem. I've got this problem where my URL route is being treated as a parameter and then express mismatches and leads to the wrong route. e.g. here are the two routes:
app.get('/byASIN/LowPrice/:asin/:price',function(req,res){});
and
app.get('/byASIN/:asin/:price', function(req, res) {});
Now all works fine but as soon as I take any param out of the first route it matches the route given below which is not what I want.
If I hit /byASIN/LowPrice/:asin/:price everything works fine but as soon as I hit /byASIN/LowPrice/:asin it matches byASIN/:asin/:price and hence calls the wrong function and crashes my server. I would like to have them match explicitly and if /byASIN/LowPrice/:asin is called, respond with some warning e.g. you're calling with one less argument. What am I missing here?
By default express Url parameters are not optinial, this is why
app.get('/byASIN/LowPrice/:asin/:price',function(req,res){});
does not match /byASIN/LowPrice/:asin, because the second parameter is missing.
However you can make a parameter optional by adding a ? to it:
app.get('/byASIN/LowPrice/:asin/:price?',function(req,res){});
this should solve your problem.
Try to define a route for /byASIN/LowPrice/:asin/:price to handle, then use a wildcard to handle everything else.
app.get('/byASIN/LowPrice/:asin/:price',function(req,res){});
app.get('*',function(req,res){});
Express matches the route by the order you insert them. If you have the loosely routes defined first, then express will use that one as the match first. An extreme example would be
app.get('*', function(req, res) {});
If this was defined as the first route, then no other route will be called (if without calling next()).
If you want express to always use the strict one first, then you will need to change the order of your routes by having the strict ones defined before the loosely ones.
It'd be nice if express support priority in the route, which could be a good solution for your problem, but until then, unfortunately, this can be fixed by ordering only :(