Hummingbird routing and requests – The.Swift.Dev.

Routing on the server aspect means the server goes to ship a response primarily based on the URL path that the consumer referred to as when firing up the HTTP request. After all the server can examine further parameters and headers to construct the ultimate response, however after we discuss routing normally, we often confer with the trail elements. Hummingbird makes use of a trie-based router, which is a quick and environment friendly approach of wanting up routes. It is fairly easy to answer HTTP request utilizing the built-in router, you may merely add your fundamental route handlers like this:

 
router.on("foo", technique: .HEAD) { _ -> HTTPResponseStatus in .okay }
router.on("foo", technique: .GET) { _ -> HTTPResponseStatus in .okay }
router.on("foo", technique: .POST) { _ -> HTTPResponseStatus in .okay }
router.on("foo", technique: .PUT) { _ -> HTTPResponseStatus in .okay }
router.on("foo", technique: .PATCH) { _ -> HTTPResponseStatus in .okay }
router.on("foo", technique: .DELETE) { _ -> HTTPResponseStatus in .okay }


router.head("foo") { _ -> HTTPResponseStatus in .okay }
router.get("foo") { _ -> HTTPResponseStatus in .okay }
router.put("foo") { _ -> HTTPResponseStatus in .okay }
router.submit("foo") { _ -> HTTPResponseStatus in .okay }
router.patch("foo") { _ -> HTTPResponseStatus in .okay }
router.delete("foo") { _ -> HTTPResponseStatus in .okay }

In Hummingbird additionally it is doable to register use a operate as a substitute of a block. Handler features might be async and throwing too, so you may mark the blocks with these key phrases or use asynchronous Swift features when registering route handlers. In the event you do not present the primary parameter, the trail as a string, the route handler goes to be hooked up to the bottom group. 👍

You can even prefix a path part with a colon, it will flip that part right into a dynamic route parameter. The parameter goes to be named after the trail part, by merely dropping the colon prefix. You may entry parameters inside your route handler by the req.parameters property. Additionally it is doable to register a number of elements utilizing a / character.

public extension HBApplication {
    
    func configure() throws {

        router.get { _ async throws in "Hiya, world!" }

        router.get("hey/:identify") { req throws in
            guard let identify = req.parameters.get("identify") else {
                throw HBHTTPError(
                    .badRequest,
                    message: "Invalid identify parameter."
                )
            }
            return "Hiya, (identify)!"
        }

        let group = router.group("todos")
        group.get(use: record)
        group.submit(use: create)
        
        let idGroup = group.group(":todoId")
        idGroup.head(use: examine)
        idGroup.get(use: fetch)
        idGroup.put(use: replace)
        idGroup.patch(use: patch)
        idGroup.delete(use: delete)

        
        router.group("todos")
            .get(use: record)
            .submit(use: create)
            .group(":todoId")
                .head(use: examine)
                .get(use: fetch)
                .put(use: replace)
                .patch(use: patch)
                .delete(use: delete)

    }

    func record(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func examine(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func fetch(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func create(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func replace(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func patch(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
    func delete(_ req: HBRequest) async throws -> HTTPResponseStatus { .okay }
}

It’s doable to make use of a wildcard character () when detecting path elements and the recursive model (*) to catch all the pieces. Additionally you should use the ${identify} syntax to catch a named request parameter even with a prefix or suffix, however you may’t insert this in the midst of a path part. (e.g. “prefix-${identify}.jpg” will not work, however “${identify}.jpg” is simply tremendous) 💡

import Hummingbird
import HummingbirdFoundation

extension HBApplication {

    func configure(_ args: AppArguments) throws {

        router.get("foo-${identify}", use: catchPrefix)
        router.get("${identify}.jpg", use: catchSuffix)
        
        router.get("*", use: catchOne)
        router.get("*/*", use: catchTwo)

        router.get("**", use: catchAll)
        
    }
    
    
    func catchOne(_ req: HBRequest) async throws -> String {
        "one"
    }

    
    func catchTwo(_ req: HBRequest) async throws -> String {
        "two"
    }
    
    
    func catchAll(_ req: HBRequest) async throws -> String {
        "all: " + req.parameters.getCatchAll().joined(separator: ", ")
    }
    
    
    func catchPrefix(_ req: HBRequest) async throws -> String {
        "prefix: " + (req.parameters.get("identify") ?? "n/a")
    }
    
    
    func catchSuffix(_ req: HBRequest) async throws -> String {
        "suffix: " + (req.parameters.get("identify") ?? "n/a")
    }
}

Additionally it is doable to edit the auto-generated response if you happen to specify the .editResponse possibility.

router.get("foo", choices: .editResponse) { req -> String in
    req.response.standing = .okay
    req.response.headers.replaceOrAdd(
        identify: "Content material-Sort", 
        worth: "utility/json"
    )
    return #"{"foo": "bar"}"#
}

Hummingbird assist for physique streaming is superb, you may stream a HTTP request physique by utilizing the .streamBody possibility. The physique stream has a sequence property, which you should use to iterate by the incoming ByteBuffer chunks when dealing with the request. 🔄

func configure() throws { 
    router.submit("foo", choices: .streamBody) { req async throws -> String in
        guard
            let rawLength = req.headers["Content-Length"].first,
            let size = Int(rawLength),
            let stream = req.physique.stream
        else {
            throw HBHTTPError(
                .badRequest,
                message: "Lacking or invalid physique stream."
            )
        }
        var depend: Int = 0
        for attempt await chunk in stream.sequence {
            depend += chunk.readableBytes
        }
        return String("(size) / (depend)")
    }
}


let app = HBApplication(
    configuration: .init(
        tackle: .hostname(hostname, port: port),
        serverName: "Hummingbird",
        maxUploadSize: 1 * 1024 * 1024 * 1024 
    )
)

As you may see you may simply entry all of the incoming headers by way of the req.headers container, it is best to be aware that this technique will return header values in a case-insensitive approach. If you wish to stream bigger information, you additionally must set a customized maxUploadSize utilizing the configuration object when initializing the HBApplication occasion.

curl -X POST http://localhost:8080/foo 
    -H "Content material-Size: 3" 
    --data-raw 'foo'

curl -X POST http://localhost:8080/foo 
    -H "content-Size: 5242880" 
    -T ~/check

You may check out streaming with a easy cURL script, be happy to experiment with these.

One other factor I might like to point out you is tips on how to entry question parameters and different properties utilizing the request object. Right here is an all-in-one instance, which you should use as a cheatsheet… 😉

router.get("bar") { req async throws -> String in
            
    struct Foo: Codable {
        var a: String
    }

    print(req.technique)
    print(req.headers)
    print(req.headers["accept"])
    print(req.uri.queryParameters.get("q") ?? "n/a")
    print(req.uri.queryParameters.get("key", as: Int.self) ?? 0)

    if let buffer = req.physique.buffer {
        let foo = attempt? JSONDecoder().decode(Foo.self, from: buffer)
        print(foo ?? "n/a")
    }
    return "Hiya, world!"
}

Anyway, there’s one further tremendous cool function in Hummingbird that I might like to point out you. It’s doable to outline a route handler, this fashion you may encapsulate all the pieces right into a single object. There’s an async model of the route handler protocol, if you happen to do not want async, you may merely drop the key phrase each from the protocol identify & the tactic. I really like this method rather a lot. 😍

struct MyRouteHandler: HBAsyncRouteHandler {

    struct Enter: Decodable {
        let foo: String
    }

    struct Output: HBResponseEncodable {
        let id: String
        let foo: String
    }
    
    let enter: Enter

    init(from request: HBRequest) throws {
        self.enter = attempt request.decode(as: Enter.self)
    }

    func deal with(request: HBRequest) async throws -> Output {
        .init(
            id: "id-1",
            foo: enter.foo
        )
    }
}

The request.decode technique makes use of the built-in decoder, which you must explicitly set for the applying, since we will talk utilizing JSON knowledge, we will use the JSON encoder / decoder from Basis to robotically rework the information.

With a view to make use of the customized route handler, you may merely register the thing kind.

import Hummingbird
import HummingbirdFoundation

public extension HBApplication {

    func configure() throws {
        
        encoder = JSONEncoder()
        decoder = JSONDecoder()
                
        
        router.submit("foo", use: MyRouteHandler.self)
    }
}

You may learn extra about how the encoding and decoding works in Hummingbird, however possibly that subject deserves its personal weblog submit. You probably have questions or options, be happy to contact me. 🙈