podspec文件的写法详解

创建pod库的时候会用到podspec文件将lib中用到的包括资源、源码、需要引用的framework，以及第三库等等组织起来。这篇文章会详细的解释一下podspec的写法。

1、podspec文件的创建

(1)pod命令创建，pod spec create [文件名]

这种方式创建出的podspec文件会带有大量的注释

（2）linux命令创建文件，touch  **.podspec

这种方式创建出了一个空的podspec文件，熟练之后可以采用这种方式。

2、podspec内容编辑

下面是从新建成功的的podspec中复制过来的，pod升级到1.1之后在新建的podspec文件中加了详细的解释，几乎不用看另外的文档就能编写podspec文件。新建的文件中未被注释的是必填项，其他为非必填项。

#
# Be sure to run `pod spec lint TestPodSpec.podspec' to ensure this is a
# valid spec and to remove all comments including this before submitting the spec.
#
# To learn more about Podspec attributes see http://docs.cocoapods.org/specification.html # To see working Podspecs in the CocoaPods repo see https://github.com/CocoaPods/Specs/ #

Pod::Spec.new do |s|

# ――― Spec Metadata ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# These will help people to find your library, and whilst it
# can feel like a chore to fill in it's definitely to your advantage. The
# summary should be tweet-length, and the description more in depth.
#

s.name = "TestPodSpec"
s.version = "0.0.1"
s.summary = "A short description of TestPodSpec."

# This description is used to generate tags and improve search results.
# * Think: What does it do? Why did you write it? What is the focus?
# * Try to keep it short, snappy and to the point.
# * Write the description between the DESC delimiters below.
# * Finally, don't worry about the indent, CocoaPods strips it!
s.description = <<-DESC
DESC

s.homepage = "http://EXAMPLE/TestPodSpec"
# s.screenshots = "www.example.com/screenshots_1.gif", "www.example.com/screenshots_2.gif"

# ――― Spec License ――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# Licensing your code is important. See http://choosealicense.com for more info.
# CocoaPods will detect a license file if there is a named LICENSE*
# Popular ones are 'MIT', 'BSD' and 'Apache License, Version 2.0'.
#

s.license = "MIT (example)"
# s.license = { :type => "MIT", :file => "FILE_LICENSE" }

# ――― Author Metadata ――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# Specify the authors of the library, with email addresses. Email addresses
# of the authors are extracted from the SCM log. E.g. $ git log. CocoaPods also
# accepts just a name if you'd rather not provide an email address.
#
# Specify a social_media_url where others can refer to, for example a twitter
# profile URL.
#

s.author = { "" => "" }
# Or just: s.author = ""
# s.authors = { "" => "" }
# s.social_media_url = "http://twitter.com/"

# ――― Platform Specifics ――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# If this Pod runs only on iOS or OS X, then specify the platform and
# the deployment target. You can optionally include the target after the platform.
#

# s.platform = :ios
# s.platform = :ios, "5.0"

# When using multiple platforms
# s.ios.deployment_target = "5.0"
# s.osx.deployment_target = "10.7"
# s.watchos.deployment_target = "2.0"
# s.tvos.deployment_target = "9.0"

# ――― Source Location ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# Specify the location from where the source should be retrieved.
# Supports git, hg, bzr, svn and HTTP.
#

s.source = { :git => "http://EXAMPLE/TestPodSpec.git", :tag => "#{s.version}" }

# ――― Source Code ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# CocoaPods is smart about how it includes source code. For source files
# giving a folder will include any swift, h, m, mm, c & cpp files.
# For header files it will include any header in the folder.
# Not including the public_header_files will make all headers public.
#

s.source_files = "Classes", "Classes/**/*.{h,m}"
s.exclude_files = "Classes/Exclude"

# s.public_header_files = "Classes/**/*.h"

# ――― Resources ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# A list of resources included with the Pod. These are copied into the
# target bundle with a build phase script. Anything else will be cleaned.
# You can preserve files from being cleaned, please don't preserve
# non-essential files like tests, examples and documentation.
#

# s.resource = "icon.png"
# s.resources = "Resources/*.png"

# s.preserve_paths = "FilesToSave", "MoreFilesToSave"

# ――― Project Linking ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# Link your library with frameworks, or libraries. Libraries do not include
# the lib prefix of their name.
#

# s.framework = "SomeFramework"
# s.frameworks = "SomeFramework", "AnotherFramework"

# s.library = "iconv"
# s.libraries = "iconv", "xml2"

# ――― Project Settings ――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #
#
# If your library depends on compiler flags you can set them in the xcconfig hash
# where they will only apply to your library. If you depend on other Podspecs
# you can include multiple dependencies to ensure it works.

#
# s.xcconfig = { "HEADER_SEARCH_PATHS" => "$(SDKROOT)/usr/include/libxml2" }
# s.dependency "JSONKit", "~> 1.4"

end


3、上文中未涉及到的内容编写（1）、部分文件非ARC方案1：将require_arc设为false,同时指定需要arc的文件夹或者文件spec.requires_arc = false
#spec.requires_arc = ['Classes/ARC/*', 'Classes/ARC1/*']
#spec.requires_arc = 'Classes/Arc'

方案2：将require_arc设为yes，同时指定除外的文件，不过使用这个方法，会导致非ARC文件被移除出原有的目录结构，不推荐使用。目前官方也是推荐采用方案1.

（2）、使用了第三方静态库，但提供方并未提供pod方案集成，需要手动导入，这个时候就需要加入vendored_lib、aries指定 s.vendored_libraries = 'Classes/**.a', 'Classes/**.a'

（3）、lib比较大，由很多文件夹构成并且文件夹相互之间并不独立，如果用subspec实现文件夹区分，在后期lint的过程中无法通过验证，除非只在本地使用。当然如果只在本地使用也不用考虑文件夹，pod会把目录结构原原本本的导入到工程里面去。