iOS：根据日志去定位网络请求发生的错误是由于服务端造成的，还是客户端造成的？

一、介绍

在项目开发中，服务端和客户端的协作尤为重要，而连接它们的最重要的环节之一就是网络请求，对于服务端而言，如果这个环节出现了错误，那么安全性就无从谈起，同时对于客户端而言，如果这个模块出现了错误，那么后续的开发就无法继续进行下去。诚然，当网络请求真的出现了问题，快速定位问题的源头就显得迫在眉睫了。本博文提供三种定位问题源头的方法，判断是服务端的原因，还是客户端的原因，避免大家找问题浪费大量的无用功。

二、ATS

一个配置网络请求方式的配置字段，NSAppTranportSecurity下的 Allow Arbitrary Loads，设置为NO，默认所有的网络请求都必须走HTTPS(SSL/TLS)协议；如果设置为YES，即是全局设置，既可以走HTTP协议，也可以走HTPPS(SSL/TLS)协议。

三、问题定位方式(查看网络请求的详细log日志)

第一种方式：配置CFNETWORK_DIAGNOSTICS=1

步骤：打开xcode的项目，找到edit scheme中的run，然后选择Arguments,给Envaironment Variables添加CFNETWORK_DIAGNOSTICS=1，最后运行程序发送网络请求即可。此时在consolelog控制器会给出网络请求详细的log日志文件路径，根据路径找到就OK了。配置如图：

点击按钮测试发送请求，我以我公司的官方来测试（本公司服务端已做了https配置） 

//  ViewController.m
//  RequestDemo
//  Created by 夏远全 on 16/12/25.
//  Copyright © 2016年 广州市东德网络科技有限公司. All rights reserved.
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor whiteColor];
    
    //发送请求
    UIButton *requestBtn = [[UIButton alloc] initWithFrame:CGRectMake(140, 200, 200, 80)];
    requestBtn.backgroundColor = [UIColor redColor];
    [requestBtn setTitle:@"requestSend" forState:UIControlStateNormal];
    [requestBtn setTitleColor:[UIColor greenColor] forState:UIControlStateNormal];
    [requestBtn addTarget:self action:@selector(requestSend) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:requestBtn];
}

//发送请求
-(void)requestSend{
    
    NSURL *URL = [NSURL URLWithString:@"https://www.biaojiepay.com"];
    NSURLRequest *request = [NSURLRequest requestWithURL:URL];
    [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue currentQueue] completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {
        NSLog(@"complete");
    }];
}
@end

打印的显示log日志文件路径如下：

2016-12-26 00:29:26.910 RequestDemo[966:51790] CFNetwork diagnostics log file created at: /Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Logs/CrashReporter/CFNetwork_com.biaojiepay.RequestDemo_966.nwlrb.log
2016-12-26 00:29:27.049 RequestDemo[966:50107] complete

此时按照提供的路径去访问该文件查看，里面记录了网络请求的详细日志信息

Dec 26 00:29:26  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:1] 00:29:26.910 {
    LoaderWhatToDo
        Request: <CFURL 0x7ff8ea816690 [0x10420ba40]>{string = https://www.biaojiepay.com/, encoding = 134217984, base = (null)}
    CachePolicy: 0
       WhatToDo: originload
    CreateToNow: 0.02034s
    } [1:1]
Dec 26 00:29:26  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:2] 00:29:26.912 {
    AddCookies Continue: request GET https://www.biaojiepay.com/ HTTP/1.1
           HTTPProtocol: Task: e8ca1fd0
    } [1:2]
Dec 26 00:29:26  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:3] 00:29:26.912 {
    DiskCookieStorage Construction: Binary{ Disk Cookies: { /Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies, <0 cookies in 0 domains> clean not writing } }
                         Accessing: <CFURL 0x7ff8e8ead9f0 [0x10420ba40]>{string = file:///Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies, encoding = 134217984, base = (null)}
                              Path: /Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies
                    Read from disk: <0 cookies in 0 domains>
                             Dirty: NO
                           Writing: NO
                            Policy: 2
    } [1:3]
Dec 26 00:29:26  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:4] 00:29:26.913 {
    DiskCookieStorage Journaling On: Binary{ Disk Cookies: { /Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies, <0 cookies in 0 domains> clean not writing } }
                               File: <CFURL 0x7ff8e8caa490 [0x10420ba40]>{string = file:///Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies, encoding = 134217984, base = (null)}
    } [1:4]
Dec 26 00:29:26  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:5] 00:29:26.913 {
    Protocol Enqueue: request GET https://www.biaojiepay.com/ HTTP/1.1
             Request: <CFURLRequest 0x7ff8ea816700 [0x10420ba40]> {url = https://www.biaojiepay.com/, cs = 0x0}
             Message: GET https://www.biaojiepay.com/ HTTP/1.1
    } [1:5]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:6] 00:29:27.001 {
    Peer certificate
    Subject Sum: www.biaojiepay.com
        Summary: Symantec Basic DV SSL CA - G1
    } [1:6]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:7] 00:29:27.008 {
    Authentication Challenge
       Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Challenge: challenge space https://www.biaojiepay.com:443/, ServerTrustEvaluationRequested (Hash c4e968442f77296)
    } [1:7]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:8] 00:29:27.008 {
    Use Credential
        Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Credential: null
    } [1:8]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:9] 00:29:27.009 {
     touchConnection
              Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Timeout Interval: 60.000 seconds
    } [1:9]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:10] 00:29:27.046 {
    Protocol Received: request GET https://www.biaojiepay.com/ HTTP/1.1
             Response: HTTP/1.1 200 OK
    } [1:10]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:11] 00:29:27.046 {
     touchConnection
              Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Timeout Interval: 60.000 seconds
    } [1:11]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:12] 00:29:27.046 {
    destroyReadStream: request GET https://www.biaojiepay.com/ HTTP/1.1
              Request: <CFURLRequest 0x7ff8ea816700 [0x10420ba40]> {url = https://www.biaojiepay.com/, cs = 0x0}
                 sent: <CFNumber 0xb000000000000c53 [0x10420ba40]>{value = +197, type = kCFNumberSInt64Type}
             received: <CFNumber 0xb00000000000d213 [0x10420ba40]>{value = +3361, type = kCFNumberSInt64Type}
            cell sent: <CFNumber 0xb000000000000003 [0x10420ba40]>{value = +0, type = kCFNumberSInt64Type}
        cell received: <CFNumber 0xb000000000000003 [0x10420ba40]>{value = +0, type = kCFNumberSInt64Type}
    } [1:12]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:13] 00:29:27.047 {
     touchConnection
              Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Timeout Interval: 60.000 seconds
    } [1:13]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:14] 00:29:27.047 {
    Response Complete
    Request: <CFURLRequest 0x7ff8ea816700 [0x10420ba40]> {url = https://www.biaojiepay.com/, cs = 0x0}
    } [1:14]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:15] 00:29:27.047 {
             Did Finish
                 Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    init to origin load: 0.021334s
             total time: 0.15739s
            total bytes: 10656
    } [1:15]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:16] 00:29:27.048 {
     touchConnection
              Loader: <CFURLRequest 0x7ff8e8c9ba60 [0x10420ba40]> {url = https://www.biaojiepay.com, cs = 0x0}
    Timeout Interval: 60.000 seconds
    } [1:16]
Dec 26 00:29:27  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:17] 00:29:27.048 {
    ~HTTPProtocol: nullptr request
          Request: null
             sent: 197
         received: 3361
        cell sent: 0
    cell received: 0
    } [1:17]
Dec 26 00:29:28  RequestDemo[966] <Notice>: CFNetwork Diagnostics [1:18] 00:29:28.914 {
    DiskCookieStorage Sync Request
       Forced: no
      isDirty: no
    isWriting: no
         File: <CFURL 0x7ff8e8eb0cb0 [0x10420ba40]>{string = file:///Users/FanLei/Library/Developer/CoreSimulator/Devices/C4192179-66A1-40C6-B09B-095C1248F68E/data/Containers/Data/Application/FE58F06E-B7BC-428E-82AE-0ED0A567ACD1/Library/Cookies/com.biaojiepay.RequestDemo.binarycookies, encoding = 134217984, base = (null)}
      Journal: yes
    Mutations: 0
    } [1:18]
 

第二种方式：采用mac自带的命令行查看网络请求日志，即/usr/bin/nscurl --ats-diagnostics --verbose https://www.biaojiepay.com(这个是带上的测试网址)

使用该命令行发送请求测试，我以我公司的官方来测试（本公司服务端已做了https配置，所有验证都会通过Pass）

终端运行结果如下：可以看到全都支持，所以pass通过

Last login: Sun Dec 25 23:55:12 on ttys003
FanLeideMacBook-Pro:~ FanLei$ /usr/bin/nscurl --ats-diagnostics --verbose https://www.biaojiepay.com
Starting ATS Diagnostics

Configuring ATS Info.plist keys and displaying the result of HTTPS loads to https://www.biaojiepay.com.
A test will "PASS" if URLSession:task:didCompleteWithError: returns a nil error.
================================================================================

Default ATS Secure Connection
---
ATS Default Connection
ATS Dictionary:
{
}
Result : PASS
---

================================================================================

Allowing Arbitrary Loads

---
Allow All Loads
ATS Dictionary:
{
    NSAllowsArbitraryLoads = true;
}
Result : PASS
---

================================================================================

Configuring TLS exceptions for www.biaojiepay.com

---
TLSv1.2
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.2";
        };
    };
}
Result : PASS
---

---
TLSv1.1
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.1";
        };
    };
}
Result : PASS
---

---
TLSv1.0
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.0";
        };
    };
}
Result : PASS
---

================================================================================

Configuring PFS exceptions for www.biaojiepay.com

---
Disabling Perfect Forward Secrecy
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

================================================================================

Configuring PFS exceptions and allowing insecure HTTP for www.biaojiepay.com

---
Disabling Perfect Forward Secrecy and Allowing Insecure HTTP
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionAllowsInsecureHTTPLoads = true;
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

================================================================================

Configuring TLS exceptions with PFS disabled for www.biaojiepay.com

---
TLSv1.2 with PFS disabled
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.2";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

---
TLSv1.1 with PFS disabled
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.1";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

---
TLSv1.0 with PFS disabled
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionMinimumTLSVersion = "TLSv1.0";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

================================================================================

Configuring TLS exceptions with PFS disabled and insecure HTTP allowed for www.biaojiepay.com

---
TLSv1.2 with PFS disabled and insecure HTTP allowed
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionAllowsInsecureHTTPLoads = true;
            NSExceptionMinimumTLSVersion = "TLSv1.2";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

---
TLSv1.1 with PFS disabled and insecure HTTP allowed
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionAllowsInsecureHTTPLoads = true;
            NSExceptionMinimumTLSVersion = "TLSv1.1";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

---
TLSv1.0 with PFS disabled and insecure HTTP allowed
ATS Dictionary:
{
    NSExceptionDomains =     {
        "www.biaojiepay.com" =         {
            NSExceptionAllowsInsecureHTTPLoads = true;
            NSExceptionMinimumTLSVersion = "TLSv1.0";
            NSExceptionRequiresForwardSecrecy = false;
        };
    };
}
Result : PASS
---

================================================================================

FanLeideMacBook-Pro:~ FanLei$ 

第三种方式：如果是服务端的问题，可以采用TLSTool来帮助你定位。（坑：TSLTool不能再Xcode8下编译）

下载链接：https://developer.apple.com/library/content/samplecode/sc1236/Introduction/Intro.html#//apple_ref/doc/uid/DTS40014927

先下载工具编译后，再在终端测试示例：我以我公司的官方来测试，端口443（本公司服务端已做了https配置，所有验证都会通过Pass）

./TLSTool s_client -connect  www.biaojiepay.com:443

GET https://www.biaojiepay.com  HTTP/1.1

Host: www.biajiepay.com