Types of Parameters in REST Requests

There are three types of parameters: two used with the GET method and one with the POST method.

• Query Params
• Route Params
• Body Params

Query & Route Params

Query params carry request data as parameters in the URL and can contain one or more parameters.

Example:

http://minhaapi.com/movies?name=transformes&duration=2&actor=octimusprime

Route params carry request data in the route itself. It's the best way to fetch, delete, or update something by ID, for example:

GET http://minhaapi.com/movies/1

DELETE http://minhaapi.com/movies/1

PUT http://minhaapi.com/movies/1

In the example above, we fetch, delete, and update the movie with ID 1.

Both change the way you write your code. Take a look:

/**
* three types of parameters
* Query params = ?test=1
* Route params = /users/1
* Request Body = { "name": "Thiago" }
*/

// Query params = ?name=thiago
// make the request in the browser: http://localhost:3333/users/?name=Thiago
server.get("/users", (req, res) => {
  const name = req.query.name;
	return res.json({ message:  `Hello ${name}` });
});


// Route Params = /users/1
// make the request in the browser: http://localhost:3333/users/1
server.get("/users/:id", (req, res) => {
// const id = req.params.id;
const { id } = req.params; // destructured with ES06
	return res.json({ message:  `Fetching user with ID: ${id}`});
});

Body Params

Body Params carry request data in the request body, as a JSON object. Always used with the POST method.

POST
{
 "name": "Thiago",
 "age": 21,
 "email": "thiago@mail.com"
}

And in the controller you grab the request to save the data into the database.

server.post("/users", (req, res){
    const { name, age, email } = req.body;

    await connection("users").insert({ name, age, email });

    return res.json({ id });
 }

The goal was to show the differences and provide proper examples.

Whenever the question of which is which comes up, just come back to this post.

In summary:

Query Param: you'll use ?name=thiago&lastname=oliveira

Route Param: you'll use /users/1