First, through documentation to understand open source project
By looking at the document, you can quickly grasp the overall structure of the software, what features it has, its key technologies involved, the principle and its ecosystem, and so on. After mastered these, then look at its source code.
We emphasize that you must go to these open-source software, the official online documentation, try not to go search for some of the Chinese translation of the document. Because the Chinese are behind the document many English documents. If the direct read English document difficult or slow, you can find what you need after reading the article, search for the corresponding Chinese version, first read through the Chinese version, then go over in front of the English version.
Most open source software, its official website and technical documentation is a relatively fixed structure.
To the official website of Kafka , for example, to see how its documentation:
1, you first need to look at Quick Start, Quick Start guide Installation of the rapid take up its environment, put it up and running, so you have this project have a perceptual awareness, but also easy to learn when you run in-depth follow-up of some example.
2, and then find some Introduction (introduction), there will be a basic introduction to the general project. You need to find some basic concepts or terminology used in the description of the project documentation. Some open source projects alone will have these basic concepts in terms of a Basic Concepts document.
3, to have a basic understanding of the project, its use can look at the scene, features and associated ecosystems introduction. In kafka official website features relevant content Use cases (use cases), EcoSystem (ecosystems, usually introduce it this project applies some typical usage scenarios for used in conjunction with which other systems at a scene, etc.) two article, some projects will be similar document describes the functions and features called features.
After you read these documents, there is a full understanding of the project, such as: the project is doing? What can solve the problem? Which is suitable for use in the scene? What are the features? how to use? Then you can go in-depth study of the principles of its implementation. But not immediately see the source code, open source projects are generally by the paper published by a giant hand to achieve it, for such open-source projects, the paper behind it is the soul of the entire project, if this papers thoroughly read and understand, implement the principle of this project will clear. For kafka, its soul thesis is: at The the Log: the What Every Software ENGINEER Should know the About Real-Time's the Unifying the Data Abstraction , corresponding Chinese translation here: Log: every software engineer should know about the real-time data unified abstraction . After completing the project soul, you can start reading the source code.