Diagramming as Code

Share on facebook
Share on twitter
Share on linkedin
Click HERE to discuss this topic in our forum!

Diagramming as Code is done in a syntax supported by PlantUML. PlantUML is an open source, plain-text diagramming syntax. One you’ve might not have heard about but one you absolutely need.

Why do I need a diagramming syntax?

That’s answered by looking at the use cases:

I’m a data architect and

  • I want to create (insert diagram type here) diagrams that my team can easily edit.
  • I want to create a visualization of my JSON or YAML files.

    I’m a project manager and

  • I want to create activity flows that I can share with my team so we can jointly edit them.
  • I want to create Work Breakdown Structures (WBS) that my team can easily edit.

    Analysis

    What each of these use cases call for is a way to visualize something and easily edit that visualization. Normally, one would have a couple of different diagramming tools to do this, each of which would need some type of training (and a license per user) to take advantage of them. But, of course, this is now the world of Compliance as Code. So why not diagrams as code? What if you could use text and a few snippets of formatting around that text, to turn that text into various forms of diagramming? What if we wanted to visualize something as simple as

This communicates with That

In order to visualize this in PlantUML, you simply need a few pointers and the type of diagram you want to draw.

Activity

An Activity diagram is basically a flowchart to represent the flow from one activity to another activity.

@startuml
:This;
:That;
@enduml

Activity

Everything begins and ends with @xxxuml. In between there isn’t much difference in the text of what is added, only the formatting. In the sequence diagram that follows, we add the communication text and slightly reformat how This and That are written.

Sequence

Sequence diagrams illustrate how messages flow through a system, also known as event diagrams. It enables the visualization of several dynamic scenarios. There is a sequential sequence of events that occurs between two lifelines, meaning both lifelines are present at the same time. According to UML, there is an upper and lower lifeline and a message flow represented by three vertical dotted lines at the bottom of the page.

@startuml
This -> That : Communication
@enduml

Sequence

Again, for the Use Case diagram, we simply re-format how This and That are written.

Use Case

The use case diagram illustrates how the system’s users interact with it. An application, system, or process that interacts with people, organizations, or external systems may benefit from the development of a use case diagram.

@startuml
:This: -> :That: : Communication
@enduml

Use Case

You should get the idea. Here are several other methods that can be used:

Class

The class diagram enables the conceptualization of application structure and the implementation of details in programming code. It is also possible to use class diagrams for data modeling.

@startuml
This -|> That: Communication
@enduml

Class

Component

Component diagrams represent the different parts of a UML diagram. In contrast to describing the system’s functionality, it represents the components used to achieve that functionality.

@startuml
[This] -> [That]: Communication
@enduml

Component

Deployment

Deployment diagrams are a kind of structure diagram used in modeling the physical aspects of an object-oriented system. They are often be used to model the static deployment view of a system (topology of the hardware).

@startuml
folder This
file That
This -> That: Communication
@enduml

Deployment

And there are other, slightly different formats, that can be used as well.

Work Breakdown Structure

A work breakdown structure defines all the things a project needs to accomplish, organized into multiple levels, and displayed graphically.

@startwbs
+ This
++ That
+++ A sub-task
++ Some other Thing
@endwbs

WBS

As you can see, PlantUML allows users to specify various types of diagrams in a simple text format similar to programming languages. It is the most popular text format for diagramming. As we showed above, it supports many different diagram types, separates each diagram element according to its function, and uses a simple, human-readable language.

How do we use diagramming as code?

Easily enough, you can create your own code-based diagrams using Plant UML by going to PlantUML’s website by clicking HERE. This will start a new page for you and you can diagram away. If you need to learn more about the various formats, you can click HERE.

If you want to learn more, you can visit our research site where we our bibliography for this topic is kept by clicking HERE.

If you want your own application that allows your team to create and track your diagrams as code, stand by… we’ll have something to show you soon!