Multiple optional route parameters in Express?

Question

I am using Express to handle a route which is in the format of /articles/:year/:month/:day, where year, month and day are optional.

• If none of the thr

Answer 1

The expressjs's guide to routing mentions:

Express uses path-to-regexp for matching the route paths; see the path-to-regexp documentation for all the possibilities in defining route paths. Express Route Tester is a handy tool for testing basic Express routes, although it does not support pattern matching.

Basically, you can use the ? character to make the parameter optional.

/articles/:year?/:month?/:day?

Answer 2

Edited for own purpose of having the 3 different options in one answer. Credit to @hjpotter92 for his regex answer.

With URL Params

With regex

app.get('/articles/:year?/:month?/:day?', function(req, res) {
  var year = req.params.year; //either a value or undefined
  var month = req.params.month;
  var day = req.params.day;
}

Without regex

var getArticles = function(year, month, day) { ... }

app.get('/articles/:year', function(req, res) {
  getArticles(req.params.year);
}
app.get('/articles/:year/:month', function(req, res) {
  getArticles(req.params.year, req.params.month);
}
app.get('/articles/:year/:month/:day', function(req, res) {
  getArticles(req.params.year, req.params.month, req.params.day);
}

Define the 3 paths you want to support and reuse the same function

With Query Params

app.get('/articles', function(req, res) {
  var year = req.query.year; //either a value or undefined
  var month = req.query.month;
  var day = req.query.day;
}

The url for this endpoint will look like this:

http://localhost/articles?year=2016&month=1&day=19

Answer 3

This type of route is not likely to work because of the underscores in the parameters passed.

app.get('/products/:product_Id/buyers/:buyer_Id', function(req, res) {
  getArticles(req.params.product_Id, req.params.buyer_Id);
}

So i suggest you use the following route system if the route is not working. There you will be able to send multiple parameters.

app.get('/products/:productId/buyers/:buyerId', function(req, res) {
  getArticles(req.params.productId, req.params.buyerId);
}