swift http请求类

KFetch.swift

import Foundation

class KFetch {
	let session: NSURLSession = NSURLSession.sharedSession()
	// url安全编码
	func escape(str: String) -> String {
		let characterSet = NSMutableCharacterSet.alphanumericCharacterSet()
		characterSet.addCharactersInString("-._ ")
		if #available(iOS 8.3, *) { 
			return str.stringByAddingPercentEncodingWithAllowedCharacters(characterSet)!.stringByReplacingOccurrencesOfString(" ", withString: "+")
		}
		let length = str.characters.count
		let num = 50
		let times = length > (length / num * num) ? length / num + 1 : length / num
		var result = ""
		for i in 0 ..< times {
			let end = i == times - 1 ? length : num * (i+1)
			let range = (str.startIndex.advancedBy(i*num)..<str.startIndex.advancedBy(end))
			result += str.substringWithRange(range).stringByAddingPercentEncodingWithAllowedCharacters(characterSet)!.stringByReplacingOccurrencesOfString(" ", withString: "+")
		}
		return result
	}
	
	// 转换成json字符串
	func jsonStringify(data: NSMutableDictionary) -> (NSData?, NSError?){
        do {
            let json = try NSJSONSerialization.dataWithJSONObject(data, options: NSJSONWritingOptions())
			return (json, nil)
        } catch {
            return (nil, error as NSError)
        }
	}
	
	func jsonParseString(string: String) -> AnyObject? {
		do {
			let data = string.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!
			let json: AnyObject! = try NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.AllowFragments)
			return json
		} catch {
			return nil
		}
	}
	
	func jsonParseNSData(data: NSData) -> AnyObject? {
		do {
			let json: AnyObject! = try NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.AllowFragments)
			return json
		} catch {
			return nil
		}
	}
	
	// 请求
	func fetch(method: String, url: String, param: [String:String]?, headers: [String: String]?, options: [String:Bool]?, 
				callback: (body: String, headers: [String:String], error: NSError?, code: Int, time: Double) -> Void ) {
		let pos = "POST" == method || "PUT" == method // post data or put data
		let opt = options != nil ? (escaped: options!["escaped"] ?? false, inner: options!["inner"] ?? false) : (escaped: false, inner: false)
		let pms = param != nil ? (opt.inner ? param!["inner"] ?? "" : param!.flatMap{"\(opt.escaped ? $0 : escape($0))=\(opt.escaped ? $0 : escape($1))"}.joinWithSeparator("&")) : ""
		let nsu = !pos && "" != pms ? url + (url.containsString("?") ? "&" : "?") + pms : url
		let req: NSMutableURLRequest = NSMutableURLRequest(URL: NSURL(string: nsu)!)
		req.HTTPMethod = method
		if headers != nil {	// 设置头部，如果有cookie，情手动调用escape编码后再传递
			for (k, v) in headers! {
				req.addValue(v, forHTTPHeaderField: k)
			}
		}
		if param != nil && ("POST" == method || "PUT" == method) { // post data
			req.HTTPBody = pms.dataUsingEncoding(NSUTF8StringEncoding)
		}
		let tim = CFAbsoluteTimeGetCurrent()
		session.dataTaskWithRequest(req, completionHandler: { (body, response, error) in 
			let b: String = body != nil ? String(data: body!, encoding: NSUTF8StringEncoding)! : ""
			let h: [String:String] = response != nil ? (response as! NSHTTPURLResponse).allHeaderFields as! [String:String] : [:]
			let c: Int = response != nil ? (response as! NSHTTPURLResponse).statusCode : 0
			let t: Double = CFAbsoluteTimeGetCurrent() - tim
			// let r = (body: b, headers: h, error: error, code: c, time: t)
			callback(body: b, headers: h, error: error, code: c, time: t)
		}).resume()
	}
}