eolas/zk/3_PUT.md

---
tags: [backend, node-js, REST, APIs]
---

# Creating a RESTful API: `PUT` requests

To demonstrate the handling of PUT requests, we will create a handler that
updates an element in the course array, based on its `id` and return the updated
entry:

```js
router.put("/:id", (req, res) => {
  const course = courses.find((c) => c.id === parseInt(req.params.id));

  if (!course)
    return res.status(404).send("A course with the given ID was not found");

  const { error } = validateCourse(req.body);

  if (error)
    return error.details.map((joiErr) => res.status(400).send(joiErr.message));

  course.name = req.body.name;
  res.send(course);
});
```

Our request:

```js
const updateCourse = async (courseChange) => {
  try {
    const resp = await axios.put("http://localhost:3000/api/courses/1", {
      name: courseChange.name,
    });
    console.log(resp.data);
  } catch (err) {
    console.error(err);
  }
};

updateCourse({ name: "A new course" });
```

Returns:

```js
{ id: 1, name: 'A new course' }
```