CDN: trunk URL couldn't be downloaded:
https://raw.githubusercontent.com/CocoaPods/Specs/master/Specs/f/e/9/CocoaMQTT/1.0.0/CocoaMQTT.podspec.json
由于项目是用CocoaPods管理，CocoaPods 1.8将CDN切换为默认的spec repo源，并附带一些增强功能！CDN支持最初是在1.7版本中引入的，最终在1.7.2中完成。 它旨在大大加快初始设置和依赖性分析。
目前项目使用pods的是1.8.4版本
Ribers-Mac:ZNB_Country2.0Riber$ pod --version
1.8.4
最近使用pods，却出现了一下错误！
[!]CDN:trunkRepoupdatefailed-17error(s):
CDN:trunkURLcouldn'tbe downloaded:https://raw.githubusercontent.com/CocoaPods/Specs/master/Specs/1/d/4/CocoaAsyncSocket/0.0.1/CocoaAsyncSocket.podspec.json,error:Operationtimedout-SSL_connect
...
按照官方文档 podfile文件中添加source源：
source 'https://github.com/CocoaPods/Specs.git'
podfile文件中添加source源后，pod install和pod update可以正常操作，但是pod search有些库却不正常。
Ribers-Mac:ZNB_Country2.0Riber$podsearchmj
[!]CDN:trunkRepoupdatefailed-3error(s):
CDN:trunkURLcouldn'tbe downloaded:https://raw.githubusercontent.com/CocoaPods/Specs/master/Specs/0/f/b/MJRefresh/0.0.1/MJRefresh.podspec.json,error:Operationtimedout-SSL_connect
CDN:trunkURLcouldn'tbe downloaded:https://raw.githubusercontent.com/CocoaPods/Specs/master/Specs/0/f/b/MJRefresh/1.4.4/MJRefresh.podspec.json,error:Operationtimedout-SSL_connect
CDN:trunkURLcouldn'tbe downloaded:https://raw.githubusercontent.com/CocoaPods/Specs/master/Specs/0/f/b/MJRefresh/2.4.9/MJRefresh.podspec.json,error:Operationtimedout-SSL_connect
Ribers-Mac:ZNB_Country2.0Riber$podsearchrbtitle
->RBTitleView(2.0.1)
简单实用的titleView
pod'RBTitleView','~> 2.0.1'
-Homepage:https://github.com/RiberWang/RBTitleDemo
-Source:https://github.com/RiberWang/RBTitleDemo.git
-Versions:2.0.1,1.0.1,1.0.0[masterrepo]
解决办法：
1. podfile文件中指定source源为master：
source 'https://github.com/CocoaPods/Specs.git'
2.执行pod repo remove trunk移除trunk源
执行完后，pod search就都正常了！
Ribers-Mac:ZNB_Country2.0Riber$ pod repo list
master
-Type:git (master)
-URL:https://github.com/CocoaPods/Specs.git
-Path:/Users/Riber/.cocoapods/repos/master
trunk
-Type:CDN
-URL:https://cdn.cocoapods.org/
-Path:/Users/Riber/.cocoapods/repos/trunk
2repos
Ribers-Mac:ZNB_Country2.0Riber$ pod repo remove trunk
Removing spec repo `trunk`
注意：podfile文件中一定要指定master源，因为现在默认是trunk源
source 'https://github.com/CocoaPods/Specs.git'
参考文章：
官方说明（英语不好的同志可在谷歌浏览器中打开使用其翻译功能）
Github Issules