画图

前言

所谓一图胜千言，特别在开发过程中，一张架构图，流程图，可以清晰的展示项目的架构和流程。

所以怎么画好一张图也是必修的软技能。

本文主要介绍下 Mermaid 和 PlantUML

Mermaid

Flowchart

流程图

A—>B A 指向 B

A—>C A 指向 C

B—>D C—>D B、C 同时指向 D

demo

graph TD;

A—>B;

A—>C;

B—>D;

C—>D;

graph TD;

A-->B;

A-->C;

B-->D;

C-->D;

{} 表示判断框

|| 表示条件

graph TB

Start(开始) —> Open[打开冰箱门]

Open —> Put[把大象放进去]

Put[把大象放进去] —> IsFit{“冰箱小不小？“}

IsFit —>|不小| Close[把冰箱门关上]

Close —> End(结束)

IsFit —>|小| Change[换个大冰箱]

Change —> Open

graph TB
    Start(开始) --> Open[打开冰箱门]
    Open --> Put[把大象放进去]
    Put[把大象放进去] --> IsFit{"冰箱小不小？"}

    IsFit -->|不小| Close[把冰箱门关上]
    Close --> End(结束)

    IsFit -->|小| Change[换个大冰箱]
    Change --> Open

Sequence diagram

序列图

participant 参与者

->> 实线连接

—>> 虚线连接

loop end 循环

Note over(left/right of) participant 挂在参与者上的提示

demo

sequenceDiagram

participant Alice

participant Bob

participant John(可以省略)

Alice->>John: Hello John, how are you?

loop Healthcheck

John->>John: Fight against hypochondria

end

Note left of Bob: Rational thoughts
prevail!

John—>>Alice: Great!

John->>Bob: How about you?

Bob—>>John: Jolly good!

sequenceDiagram
    participant Alice
    participant Bob
    Alice->>John: Hello John, how are you?
    loop Healthcheck
        John->>John: Fight against hypochondria
    end
    Note left of John: Rational thoughts <br/>prevail!
    John-->>Alice: Great!
    John->>Bob: How about you?
    Bob-->>John: Jolly good!

Gantt diagram

甘特图

dateFormat YYYY-MM-DD 时间格式

title 标题

excludes 排除某个日期

demo

gantt

dateFormat YYYY-MM-DD

title Adding GANTT diagram to mermaid

excludes weekdays 2014-01-10

section A section

Completed task :done, des1, 2014-01-06,2014-01-08

Active task :active, des2, 2014-01-09, 3d

Future task : des3, after des2, 5d

Future task2 : des4, after des3, 5d

gantt
dateFormat  YYYY-MM-DD
title Adding GANTT diagram to mermaid
excludes weekdays 2014-01-10

section A section
Completed task            :done,    des1, 2014-01-06,2014-01-08
Active task               :active,  des2, 2014-01-09, 3d
Future task               :         des3, after des2, 5d
Future task2               :         des4, after des3, 5d

PlantUML

@startuml @enduml 成对出现，一前一后

时序图

与 Mermaid 的使用类似，-> 实现，—> 虚线，participant 来声明参与者

如果参与者之间本身有连接的话，不需要显示申明

@startuml
participant Foo
Alice -> Bob: Authentication Request
Bob --> Alice: Authentication Response

Alice -> Bob: Another authentication Request
Alice <-- Bob: Another authentication Response
@enduml
@startuml
participant Foo
Alice -> Bob: Authentication Request
Bob --> Alice: Authentication Response

Alice -> Bob: Another authentication Request
Alice <-- Bob: Another authentication Response
@enduml

actor 角色

activate/deactivate

#red 指定颜色

demo

@startuml

skinparam backgroundColor #EEEBDC

skinparam handwritten true

actor Customer #red

Customer -> “login()” : username & password

“login()” -> Customer : session token

activate “login()”

Customer -> “placeOrder()” : session token, order info

“placeOrder()” -> Customer : ok

Customer -> “logout()”

“logout()” -> Customer : ok

deactivate “login()”

@enduml

@startuml
    skinparam backgroundColor #EEEBDC
    skinparam handwritten true
    actor Customer  #red
    Customer -> "login()" : username & password
    "login()" -> Customer : session token
    activate "login()"
    Customer -> "placeOrder()" : session token, order info
    "placeOrder()" -> Customer : ok
    Customer -> "logout()"
    "logout()" -> Customer : ok
    deactivate "login()"
@enduml

小结

画图前建议先把下面两个 URL 先看一下

本文只是简单整理下 Mermaid 和 PlantUML 提供的画图的能力，根据实际的项目，可以选择合适的图玩一玩

PlantUML 相比 Mermaid，多了些内置的 actor 和颜色，更丰富。

Reference

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