Basic NSURLSession API.

Author: danieleggert

CoreFoundation/Base.subproj/ForSwiftFoundationOnly.h

@@ -23,9 +23,11 @@
 #include <CoreFoundation/CFXMLInterface.h>
 #include <CoreFoundation/CFRegularExpression.h>
 #include <CoreFoundation/CFLogUtilities.h>
+#include <CoreFoundation/CFURLSessionInterface.h>
 #include <CoreFoundation/ForFoundationOnly.h>
 #include <fts.h>
 
+
 _CF_EXPORT_SCOPE_BEGIN
 
 struct __CFSwiftObject {

CoreFoundation/URL.subproj/CFURLSessionInterface.c

@@ -334,7 +334,7 @@ extension NSData {
             let cond = NSCondition()
             var resError: NSError?
             var resData: NSData?
-            let task = session.dataTaskWithURL(url, completionHandler: { (data: NSData?, response: NSURLResponse?, error: NSError?) -> Void in
+            let task = session.dataTask(with: url, completionHandler: { (data: NSData?, response: NSURLResponse?, error: NSError?) -> Void in
                 resData = data
                 resError = error
                 cond.broadcast()

CoreFoundation/URL.subproj/CFURLSessionInterface.h

@@ -183,6 +183,13 @@ public class NSHTTPURLResponse : NSURLResponse {
     /// `[NSObject: AnyObject]` type that Darwin Foundation uses.
     public let allHeaderFields: [String: String]
 
+    /// The value of a specific header field
+    ///
+    /// Uses case-insensitive matching to find the header field with the name.
+    internal func value(forHeaderField field: String) -> String? {
+        return valueForCaseInsensitiveKey(field, fields: allHeaderFields)
+    }
+    
     /*!
         @method localizedStringForStatusCode:
         @abstract Convenience method which returns a localized string

Foundation.xcodeproj/project.pbxproj

@@ -0,0 +1,137 @@
+// Foundation/NSURLSession/Configuration.swift - NSURLSession & libcurl
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+// -----------------------------------------------------------------------------
+///
+/// These are libcurl helpers for the NSURLSession API code.
+/// - SeeAlso: https://curl.haxx.se/libcurl/c/
+/// - SeeAlso: NSURLSession.swift
+///
+// -----------------------------------------------------------------------------
+
+
+internal extension NSURLSession {
+    /// This is an immutable / `struct` version of `NSURLSessionConfiguration`.
+    struct Configuration {
+        /// identifier for the background session configuration
+        let identifier: String?
+        
+        /// default cache policy for requests
+        let requestCachePolicy: NSURLRequestCachePolicy
+        
+        /// default timeout for requests.  This will cause a timeout if no data is transmitted for the given timeout value, and is reset whenever data is transmitted.
+        let timeoutIntervalForRequest: NSTimeInterval
+        
+        /// default timeout for requests.  This will cause a timeout if a resource is not able to be retrieved within a given timeout.
+        let timeoutIntervalForResource: NSTimeInterval
+        
+        /// type of service for requests.
+        let networkServiceType: NSURLRequestNetworkServiceType
+        
+        /// allow request to route over cellular.
+        let allowsCellularAccess: Bool
+        
+        /// allows background tasks to be scheduled at the discretion of the system for optimal performance.
+        let discretionary: Bool
+        
+        /// The proxy dictionary, as described by <CFNetwork/CFHTTPStream.h>
+        let connectionProxyDictionary: [NSObject : AnyObject]?
+        
+        /// Allow the use of HTTP pipelining
+        let httpShouldUsePipelining: Bool
+        
+        /// Allow the session to set cookies on requests
+        let httpShouldSetCookies: Bool
+        
+        /// Policy for accepting cookies.  This overrides the policy otherwise specified by the cookie storage.
+        let httpCookieAcceptPolicy: NSHTTPCookieAcceptPolicy
+        
+        /// Specifies additional headers which will be set on outgoing requests.
+        /// Note that these headers are added to the request only if not already present.
+        
+        let httpAdditionalHeaders: [String : String]?
+        /// The maximum number of simultanous persistent connections per host
+        let httpMaximumConnectionsPerHost: Int
+        
+        /// The cookie storage object to use, or nil to indicate that no cookies should be handled
+        let httpCookieStorage: NSHTTPCookieStorage?
+        
+        /// The credential storage object, or nil to indicate that no credential storage is to be used
+        let urlCredentialStorage: NSURLCredentialStorage?
+        
+        /// The URL resource cache, or nil to indicate that no caching is to be performed
+        let urlCache: NSURLCache?
+        
+        /// Enable extended background idle mode for any tcp sockets created.
+        let shouldUseExtendedBackgroundIdleMode: Bool
+        
+        let protocolClasses: [AnyClass]?
+    }
+}
+internal extension NSURLSession.Configuration {
+    init(URLSessionConfiguration config: NSURLSessionConfiguration) {
+        identifier = config.identifier
+        requestCachePolicy = config.requestCachePolicy
+        timeoutIntervalForRequest = config.timeoutIntervalForRequest
+        timeoutIntervalForResource = config.timeoutIntervalForResource
+        networkServiceType = config.networkServiceType
+        allowsCellularAccess = config.allowsCellularAccess
+        discretionary = config.discretionary
+        connectionProxyDictionary = config.connectionProxyDictionary
+        httpShouldUsePipelining = config.httpShouldUsePipelining
+        httpShouldSetCookies = config.httpShouldSetCookies
+        httpCookieAcceptPolicy = config.httpCookieAcceptPolicy
+        httpAdditionalHeaders = config.httpAdditionalHeaders.map { convertToStringString(dictionary: $0) }
+        httpMaximumConnectionsPerHost = config.httpMaximumConnectionsPerHost
+        httpCookieStorage = config.httpCookieStorage
+        urlCredentialStorage = config.urlCredentialStorage
+        urlCache = config.urlCache
+        shouldUseExtendedBackgroundIdleMode = config.shouldUseExtendedBackgroundIdleMode
+        protocolClasses = config.protocolClasses
+    }
+}
+
+// Configure NSURLRequests
+internal extension NSURLSession.Configuration {
+    func configure(request: NSMutableURLRequest) {
+        httpAdditionalHeaders?.forEach {
+            guard request.value(forHTTPHeaderField: $0.0) == nil else { return }
+            request.setValue($0.1, forHTTPHeaderField: $0.0)
+        }
+    }
+    func setCookies(on request: NSMutableURLRequest) {
+        if httpShouldSetCookies {
+            //TODO: Ask the cookie storage what cookie to set.
+        }
+    }
+}
+// Cache Management
+private extension NSURLSession.Configuration {
+    func cachedResponse(forRequest request: NSURLRequest) -> NSCachedURLResponse? {
+        //TODO: Check the policy & consult the cache.
+        // There's more detail on how this should work here:
+        // <https://developer.apple.com/library/prerelease/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLRequest_Class/index.html#//apple_ref/swift/enum/c:@E@NSURLRequestCachePolicy>
+        switch requestCachePolicy {
+        default: return nil
+        }
+    }
+}
+
+private func convertToStringString(dictionary: [NSObject:AnyObject]) -> [String: String] {
+    //TODO: There's some confusion about [NSObject:AnyObject] vs. [String:String] for headers.
+    // C.f. <https://github.com/apple/swift-corelibs-foundation/pull/287>
+    var r: [String: String] = [:]
+    dictionary.forEach {
+        let k = String($0.key as! NSString)
+        let v = String($0.value as! NSString)
+        r[k] = v
+    }
+    return r
+}