API classification of

• The difference between the API and SDK
• API classification of
• Based on source interfaces
• Based interface protocol
• Other extension

The difference between the API and SDK

API=Application Programming Interface, 应用程序编程接口
SDK=Software Development Kit，软件开发包
二者关键的区别在于 接口和包 上
SDK一定定义了接口，但API不一定有包
比如Windows SDK里面包含了各种lib、dll

API classification of

个人理解，API大致分为两类
一类是基于源码的接口
一类是基于协议的接口

Based on source interfaces

• Scenes
  • Interface usually in the process of adopting such an interface
  • When the interface needs across process control, and communication is a proprietary protocol, usually using such interface
  • In order to reduce the threshold of the second development, the use of such interfaces will
• Form provided
  • Generally, such interfaces are based on C / C ++ provides, because other languages ​​also have a mechanism to call
  • Provides the interface header file, lib, dll (a or so)
• advantage
  • It allows developers to more easily call
  • General duplex protocol is the underlying protocol, you can do better server push
• Shortcoming
  • Maintenance costs
  • We need to consider a variety of cross-platform process
  • Upgrade compatibility issues need to be considered

Based interface protocol

• Scenes
  • C / SB / S and other inter-process communication model
  • The server can provide external standard communication protocol
• Form provided
  • To develop a standard communication protocol interfaces encoding protocol +
  • At present more combinations is Http + Json or Http + Xml
  • Of course there grpc used http2 + pb
• advantage
  • More open, more compatible with the current development model of the Internet
  • More attention into the server
  • The upgrade can be better
• Shortcoming
  • Http itself is the problem, push too much trouble
  • Secondary developers need to deal with their client logic

Other extension

• About RESTFul and RPC
  • RESTFul often heard the API, is used for the communication protocol specification
    • Operation requires strict compliance with POST GET PUT DELETE
    • URL needs to ensure that each URL represents an object or a class of objects, can not contain verbs
  • RPC is used to invoke the specification between C / S or B / S
    • google's grpc
    • facebook的thrift

Original: Big Box  classification of API