Fix the iOS code signing issue when using Jenkins

This week I setup the Jenkins on my Mac and try to build iOS applications. unfortunately I got the code signing issues, either I use xcode plugin or xcode command line tool. Through a couple days of googling and I could not find any solution that works for me, but I finally solve this issue by myself through different try out, and the solution is such an easy, now I would like to share with my solution.

The core reason is Jenkins is running as daemon mode in Mac, just assume it is a different user - "Jenkins", so it will not have access to the keychain or provision profile as a you login using your credentials, which cause the code signing issue.
I found I have following 2 errors

1. "Code Sign error: There are no valid certificate/private key pairs in the default keychain"
Solution: Copy your iPhone developer certificate from "login" keychain to "System" keychain.
Detailed steps:
  open the "Keychain Access" application, click the login tab, right click the certificate like "iPhone Developer: your_name (XXXXXXX)", choose copy, then click the "System" tab, right click mouse, choose "Paste 2 items"; you might need to do the same thing with the certificate like "iPhone Distribution: your_name".

After doing this, you will get the second error.
2. "Code Sign error: Provisioning profile 'xxxxx-xxxx-xxxx-xxxxx' can't be found"
Solution: Copy the provision profile to Jenkins user folder.
The provision profile is under in the folder
/YourUserName/Library/MobileDevice/Provisioning Profiles,
for example in my machine, the provision profile files are under /Users/steve/Library/MobileDevice/Provisioning Profiles
In the mac, the Jenkins will be in /Users/Shared/Jenkins, create the following folder:
/Users/Shared/Jenkins/Library/MobileDevice/Provisioning Profile,  then copy the .mobileprovision file to this folder.

After doing this, the code signing issues will be fixed. Hope my finding will be helpful to other Jenkins users.