mirror of https://github.com/vapor/docs.git
105 lines
2.3 KiB
Markdown
105 lines
2.3 KiB
Markdown
---
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currentMenu: http-response-representable
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---
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> Module: `import HTTP`
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# ResponseRepresentable
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Traditionally HTTP servers take a `Request` and return a `Response`. Vapor is no different, but we can take advantage of Swift's powerful protocols to be a bit more flexible to the user facing api.
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Let's start with the definition of `ResponseRepresentable`
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```swift
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public protocol ResponseRepresentable {
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func makeResponse() throws -> Response
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}
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```
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By conforming to this protocol, we can more flexibly return things that conform instead of creating the response manually each time. Vapor provides some of these by default. Including (but not limited to):
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### String
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Because string conforms to `ResponseRepresentable`, we can return it directly in a Vapor route handler.
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```swift
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drop.get("hello") { request in
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return "Hello, World!"
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}
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```
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### JSON
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`JSON` can be returned directly instead of recreating a response each time.
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```swift
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drop.get("hello") { request in
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return try JSON(node: [
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"hello": "world",
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"some-numbers": [
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1,
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2,
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3
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]
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]
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)
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}
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```
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### Response
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Of course, we can also return Responses for anything not covered:
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```swift
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drop.get("hello") { request in
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return Response(status: .ok, headers: ["Content-Type": "text/plain"], body: "Hello, World!")
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}
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```
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## Conforming
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All we need to do to return our own objects is conform them to `ResponseRepresentable`. Let's look at an example type, a simple blog post model:
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```swift
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import Foundation
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struct BlogPost {
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let id: String
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let content: String
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let createdAt: NSDate
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}
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```
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And now, let's conform it to response representable.
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```swift
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import HTTP
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import Foundation
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extension BlogPost: ResponseRepresentable {
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func makeResponse() throws -> Response {
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let json = try JSON(node:
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[
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"id": id,
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"content": content,
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"created-at": createdAt.timeIntervalSince1970
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]
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)
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return try json.makeResponse()
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}
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}
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```
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> Don't forget to import HTTP.
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Now that we've modeled our BlogPost, we can return it directly in route handlers.
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```swift
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drop.post("post") { req in
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guard let content = request.data["content"] else { throw Error.missingContent }
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let post = Post(content: content)
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try post.save(to: database)
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return post
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}
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```
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