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Vapor HTTPClient跟踪重定向

vapor swift

Paul Peelen · 技术社区 · 6 年前

我不知道如何跟踪来自外部URL的重定向。我访问的网址是因为某种原因给了我301,即使我没有收到它的邮差。我想知道怎样才能让httpclient跟踪这个重定向,或者我是否做了什么错误来获得301。

我确实读过 this PR 但我认为这已经不相关了。也不 HTTPClient documentation 封面重定向。在下面的示例中,我将用户代理设置为与邮递员相同,以便尽可能模拟邮递员的请求。

我的代码到目前为止:

import Vapor
import HTTP

protocol DataFetching {
  func getFromURL(_ url: URL, on worker: Worker) throws -> Future<HTTPResponse>
}

class DataFetcher: DataFetching {

  enum Error: Swift.Error {
    case unknown
  }

  func getFromURL(_ url: URL, on worker: Worker) throws -> Future<HTTPResponse> {

    guard let host = url.host else { throw Error.unknown }

    var headers = HTTPHeaders()
    headers.replaceOrAdd(name: .userAgent, value: "PostmanRuntime/7.4.0")
    headers.replaceOrAdd(name: .accept, value: "*/*")
    headers.replaceOrAdd(name: .cacheControl, value: "no-cache")
    headers.replaceOrAdd(name: .applyToRedirectRef, value: "true")
    headers.replaceOrAdd(name: .acceptEncoding, value: "gzip, deflate")

    let httpRequest = HTTPRequest(method: .GET, url: url, version: HTTPVersion(major: 1, minor: 1), headers: headers)

    return HTTPClient.connect(hostname: host, on: worker).flatMap { client in
      return client.send(httpRequest)
    }
  }
}

我错过了什么?

1 回复 | 直到 6 年前

Paul Peelen 6 年前

我最终使用了urlsession。这是我的最终结果,对我来说很好:

enum DataFetcherErrors: Error {
  case didNotRecieveData
  case unknown
}

protocol DataFetching {
  func getFromURL(_ url: URL, on worker: Worker) throws -> Future<Data>
}

class DataFetcher: DataFetching {

  let urlSession: URLSession
  private var headers = [
    "Accept": "*/*",
    "User-Agent": "DataFetcher",
    "Cache-Control": "no-cache",
    "Accept-Encoding": "gzip, deflate"
  ]

  init(urlSession: URLSession = .shared) {
    self.urlSession = urlSession
  }

  func getFromURL(_ url: URL, on worker: Worker) throws -> Future<Data> {
    let promise = worker.eventLoop.newPromise(Data.self)

    request(url: url) { (data, response, error) in
      if let error = error {
        promise.fail(error: error)
      }

      guard let data = data else {
        promise.fail(error: DataFetcherErrors.didNotRecieveData)
        return
      }

      promise.succeed(result: data)
    }

    return promise.futureResult
  }
}

private extension DataFetcher {

  func request(url: URL, completionHandler: @escaping ((Data?, URLResponse?, Error?) -> Void)) {
    var request = URLRequest(url: url)
    request.httpMethod = "GET"

    headers.forEach { fieldName, value in
      request.setValue(value, forHTTPHeaderField: fieldName)
    }

    let task = urlSession.dataTask(with: request, completionHandler: completionHandler)
    task.resume()
  }
}