vapor-docs/2.0/docs/json/overview.md

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# JSON
JSON is an integral part of Vapor. It powers Vapor's [Config](../settings/config.md) and is easy to use in both requests and responses.
## Request
JSON is automatically available in `request.data` alongside Form URL Encoded, Form Data, and Query data. This allows you to focus on making a great API, not worrying about what content types data will be sent in.
```swift
drop.get("hello") { request in
guard let name = request.data["name"]?.string else {
throw Abort(.badRequest)
}
return "Hello, \(name)!"
}
```
This will return a greeting for any HTTP method or content type that the `name` is sent as, including JSON.
### JSON Only
To specifically target JSON, use the `request.json` property.
```swift
drop.post("json") { request in
guard let name = request.json?["name"]?.string else {
throw Abort(.badRequest)
}
return "Hello, \(name)!"
}
```
The above snippet will only work if the request is sent with JSON data.
## Response
To respond with JSON, simply create a `JSON` object and add values to it.
```swift
drop.get("version") { request in
var json = JSON()
try json.set("version", 1.0)
return json
}
```
## Convertible
Making your classes and structs JSON convertible is a great way to interact with APIs in an organized and DRY way.
### Representable
When something conforms to `JSONRepresentable`, it can be converted into JSON.
```swift
extension User: JSONRepresentable {
func makeJSON() throws -> JSON {
var json = JSON()
try json.set("id", id)
try json.set("name", name)
try json.set("age", age)
return json
}
}
```
Now you can simply return `user.makeJSON()` in your routes.
```swift
drop.get("users", User.init) { req, user in
return try user.makeJSON()
}
```
You can even go a step further and conform your model to `ResponseRepresentable`. Since it's already `JSONRepresentable`
you will get the conformance for free.
```swift
extension User: ResponseRepresentable { }
```
Now you can return the model by itself. It will automatically call `.makeJSON()`.
```swift
drop.get("users", User.init) { req, user in
return try user
}
```
### Initializable
When something conforms to `JSONInitializable`, it can be created from JSON.
```swift
extension User: JSONInitializable {
convenience init(json: JSON) throws {
try self.init(
name: json.get("name"),
age: json.get("age")
)
}
}
```
Now you can simply call `User(json: ...)` to create a user from JSON.
```swift
drop.post("users") { req in
guard let json = req.json else {
throw Abort(.badRequest)
}
let user = try User(json: json)
try user.save()
return user
}
```