"The author takes you to analyze agile development - Scrum"
foreword
The topic of agile has been popular for a long time. The author remembers that he has been in contact with agile intermittently since 2008, but what is agile? Maybe the author himself did not fully understand it before. Is it a technology? Or a methodology? And how is it different from the traditional waterfall development model? With these questions in mind, the author has carried out effective and reasonable integration of these fragmented information points and the knowledge points expanded recently from different R&D teams and projects one after another, in order to be better in the technical team. Use agile and feel the benefits of agile, hence this blog post.
text
Maybe students who often read my blog posts will find it strange. The format of my blog posts is generally in the form of elementary school students’ compositions. With a beautiful preface and rigorous table of contents, why does this blog post have no table of contents? This is the case, after all, the author is not a professional agile development expert , so I can only talk about it in general, so the directory will hinder the author's mood to write blog posts, please understand.
So, let's start with a few questions from the preface. To put it simply, agile is not a technology, but just a development process. Unlike the traditional waterfall model, the waterfall model focuses on documents as the core, that is, document-driven, and developers strictly follow the documents no matter what they do. The plans formulated above are executed in an orderly manner. Agile is people-centered , emphasizing the communication between people (Face to Face) and the iterative development of projects .
In fact, the so-called iterative development refers to dividing the original relatively complex task into multiple small tasks according to the task cycle, until the task is small enough, then gradually complete these small tasks in the form of small cycles, so that each cycle It is a task iteration, and each iteration produces a product that can be delivered online. I hope everyone pays attention that the only purpose of using agile development is to exchange an effective and reasonable software development process for the efficient output rate of the technical team . Otherwise, any form of development process is meaningless. So the rational use of agile can really make your team full of passion and efficient code production rate.
This blog post will only explain Scrum, not XP. Of course, in the actual project development process, Scrum and XP are often executed together. There are 3 very important roles in the Scrum development process as follows:
1. Product Owner: Define specific requirements, formulate launch plans and output content, and have the power to pass the output of the Scrum Team;
2. Process Manager (Scrum Master): Promote the implementation and follow-up of the Scrum development process ;
3. Scrum Team: Carry out specific construction under the Scrum development process;
The following figure shows a detailed attempt of the Scrum development process:
Figure A-1 Scrum development model
In Figure A-1, 2-4 weeks refer to an iterative process (Sprint), that is to say, the Scrum Team should complete the development content of an iteration at the fastest speed, so this process is called Sprint. So how should you play the Scrum development process in the near future? First, the Product Owner needs to formulate a clear list of requirements arranged in priority order, this process is referred to as the Product Backlog; then the Scrum Team team needs to make a rough manpower estimate and cycle estimate based on the Product Backlog list; then, The technical leader of the Scrum Team and the Product Owner need to select a Story as the target of the first iteration through a task iteration meeting (Sprint Planning Meeting). Since the Story still needs to be refined, a Sprint Backlog will be formed at the end; the Scrum Team will be responsible for
Sprint Backlog, however, each member of the Scrum Team will divide the Sprint Backlog more finely according to the requirements, until the task is small enough, and then the cycle consumed by each task should be locked in 1-2 days to digest, in short The entire Sprint Backlog will be completed within 2-4 weeks; in the process of implementing the Sprint Backlog every day, the Scrum Team will do a daily Scrum Meeting as the first thing to do every day, and the time is best controlled within 5-15 minutes , and everyone in the Scrum Team should take turns to speak , explaining what was done yesterday, what was not done, what was done, what problems were encountered, etc. If the task has been completed, then Sprint burn down and update it on the blackboard; When a Sprint Backlog is completed, it means the end of a task iteration, at this time it is necessary to perform a demonstration meeting, because the Product Owner needs to be accepted and has the right to pass. In short, these are the Scrum development processes that the author came into contact with in the actual development process. The format of the stand is as follows:
Figure A-2 Station Meeting Form
Let me say here that the small blackboard is the key to executing Scrum, because the small blackboard clearly defines the progress of the Scrum Team, so the small blackboard can also be called the task version . To put it simply, the task viewing board can be divided into three types of work status: unfinished, in progress, completed, etc., and pasted with small cards of different colors ( each color of the small card represents a member of the Scrum Team). ), and write down the specific task plan. Assuming that a certain task has been completed, then you need to paste the small card into the completed area. In fact, this can clearly show the work progress of everyone in the team. Suppose you If one of the mission points stayed in the unfinished area for many days, then there must be a problem in which link.
Figure A-3 Task Kanban
Finally, let me mention that any new requirements are not allowed to be added in the process of implementing the Sprint Backlog by the Scrum Team. The Scrum Master needs to strictly check, and the development team is not allowed to receive harassment .