pumla

pumla = PlantUML Manager

Idea

It seems that PlantUML is quite liked by a lot of software developers. With PlantUML they do architecture documentation even without an architect forcing them to do. One of the reasons for that is the text-based and code-like approach, I guess.

But PlantUML has a big drawback from my point of view (the systems and software architect point of view, but I am also a software developer): with PlantUML you basically program diagrams. What the architect would like to do is to "draw/model/program" a system/software model with the possibility to re-use the once-modelled elements in different views on different diagrams exposing different aspects, attributes, interactions and relations.

So the approach with pumla is to dock onto the success of PlantUML but to extend it in order to get rid of the "no re-usable model" drawback (and some other smaller drawbacks and limitations).

Therefore, in order to enable systematic re-use for architecture models with PlantUML, pumla is intended to be an extension around PlantUML to organize and enable this systematic re-use.

Goals, Use Cases & Principles

click to expand!

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• Architecture modelling of bigger software solutions using PlantUML
• Have the same model elements in different diagrams as single source entities
• Keep the architecture descriptions close to the Source Code --> Architecture as text
• Allow modularity of the architecture elements and loose coupling --> no complicated include mechanisms with "paths" that then make refactoring hard --> architecture modelling files can be everywhere in the source tree and will be found.
• enable better "bridging"/mixing of the dynamic and the static world, e.g. state or sequence diagrams with deployment diagrams.
• Create an arc42 architecture documentation based on common PlantUML description patterns with almost no effort.

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Context Diagram

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Here's an overview of the idea.

In blue you can see the parts developed as pumla and how they interact with other applications and documents during software development.

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Getting Started

Simple example

Here is a quick example from scratch to show you how to use pumla to make re-use of PlantUML-modelled elements. It consists of two steps: first you model the element in PlantUML with little pumla-specific adders to make it re-usable. Then as second step, you create a new diagram where you just re-use the element you modelled before on that diagram by putting it there with just one pumla command. See the following chapters for the details:

Defining a re-usable element

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Of course you need to have pumla installed. See further below for installation instructions.

Then:

• Create a folder for the example.
• Change into that folder.
• Call pumla setupprj. That prepares your example folder as a project containing a pumla architecture documentation. 3 files should have been created in the folder: pumla_macros.puml, pumla_blacklist.txt and pumla_project_config.puml.
• Create a file like this:

File: simpleElement.puml

'PUMLAMR
@startuml
!include pumla_macros.puml
!include modelrepo_json.puml

PUMLAReUsableAsset("A simple Element", simpleElement, component, "<<block>>") {
    PUMLARUAPutTaggedValues()

    PUMLARUAInternals() {
        component compA
        component "compB"
        component "signal processing"
    }
}

PUMLARUAAddTaggedValue("Vendor", "A GmbH")

PUMLARUAInterface("interfaceA", ifA_simpleELement, "out")

note as dn_simpleElement
    Example of a simple element.
    This can be re-used.
end note

PUMLARUADescr(dn_simpleElement)

PUMLAReUsableAssetFinalize()
@enduml

After saving the file, call pumla update. The model repository database got created in a file called modelrepo_json.puml. The model repo contains the "simpleElement" that you created. So this can now easily be re-used on other diagrams, see next step.

If you are using a PlantUML plugin in your editor, you directly see the code of the file rendered to a diagram like this:

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Re-using the element on another diagram

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Create a PlantUML diagram like this:

File: simpleDiagram.puml

@startuml
!include pumla_macros.puml
!include modelrepo_json.puml

!$PUMVarShowDescr = %false()
!$PUMVarShowInterfaces = %false()
!$PUMVarShowBodyInternals = %true()
!$PUMVarShowTaggedValues = %true()

title Put a re-usable element onto the diagram

' put the "simpleElement" from the model repository
' onto the diagram
PUMLAPutElement(simpleElement)

note as n1
    The re-usable element "simpleElement"
    is put onto the diagram.
    
    Via the global variables, showing the
    description of the element as well as
    the interfaces is turned off.
    
    So you have a different, more restrained
    view on the element on this diagram.
end note

@enduml

This works out of the box, as everything the diagram needs is already there, the pumla_macros.puml as well as the model repo containing the "simpleElement".

Again, in your editor with PlantUML plugin or when rendering the file explicitly with PlantUML, your diagram looks like this:

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Further examples

For more examples showing off the functionality and magic of pumla, see the following examples:

Simple Hierarchical System

follow this link to the Simple Hierarchical System example

WeatherStation examples

This is a comprehensive set with a bigger model and a lot of different diagrams. Follow the following link to an overview on these examples:

follow this link to the WeatherStation examples

C4 example

This is an advanced example showing how to re-use C4 model elements with pumla. Follow this link to an overview and description an that example:

follow this link to the C4 example

Working with the examples

In order to play around with the previously mentioned examples, you need to initialise the examples repository to work on your system. To do that, take the following steps starting in the pumla package root directory (after following the installation steps of the next chapter, you are already there):

click to expand: prepare example "WeatherStation"

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Example: WeatherStation

This is a comprehensive example showing off the standard PlantUML and pumla features.

cd test/examples/WeatherStation
pumla init
pumla update

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click to expand: prepare example "C4example"

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Example: C4example

This is an example to show how the C4model extension of PlantUML can be used and also C4model elements can be made re-usable.

cd test/examples/C4example
pumla init
pumla update

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click to expand: Explanation to preparation of both examples

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The "init" step in both examples creates or updates the file "pumla_macros.puml", that connects your repo with the pumla installation/deployment on your computer. This step must only be executed once after a checkout/clone.

The "update" step creates or updates the modelrepo_json.puml with the current content of the examples repository and also considers the file structure/paths on your computer. This step needs to be executed everytime you changed something on the model repository, e.g. added a new re-usable architecture model element or changed an existing one.

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Simplified PlantUML diagram generation

In order to easily generate picture files (like .png) for the text-based diagram sources (PlantUML or pumla files), pumla has an easy-to-use installation mechanism for the PlantUML JAR lib. This downloads and installs a compatible version of the PlantUML JAR lib. To install that just call the following command (only needed once after pumla installation):

pumla installplantuml

If PlantUML has been installed that way successfully, you can use the pumla command line tool to generate corresponding picture files like this:

Change to an example source file folder:

cd test/examples/WeatherStation/anotherClass

Generate a picture file (default is .png):

  pumla gendiagram ./anotherClass.puml

Generate an SVG picture file:

  pumla gendiagram ./anotherClass.puml svg

Installation

Install latest development

To get the latest developments, clone this git repo to a place somewhere on your Mac/Raspberry Pi or other Unix-like system:

git clone https://github.com/DrMarkusVoss/pumla.git
cd pumla
pip install -e .
pumla setup

After that you should be able to call pumla <cmd> at any place, e.g. pumla init or pumla update.

Install an official release

The following instructions work only for release equal to or newer than 0.8.3. For installation of older releases, please read the installation instructions in the README.md of the downloaded archive.

To get a release, do the following:

• go to the Release page, choose a release version and download the corresponding Source Code archive (.zip or .tar.gz).
• extract the archive
• change to the unpacked pumla folder, e.g. cd pumla-0.8.3
• install pumla with: pip install .
• call from same folder: pumla setup

User's Guide

You can directly dive into the details by taking a look into the User's Guide:

Link to User's Guide

Modelling Guideline

This guideline gives you hints and rules in order to write pumla conforming PlantUML files, so that you can get the benefit of model element and diagram re-use:

Link to Modelling Guideline

Development Environment

I use PyCharm as development environment for developing pumla with the PlantUML integration plugin and the internal bundled markdown handling activated. That way you have fast previews of the .puml and markdown files.

System Requirements

• currently pumla supports only Unix-like systems like Linux, Unix, Raspbian/Raspberry Pi OS and MacOS. I didn't do the file paths handling in a way that it works across Windows and Unix platform, as I also do not have a Windows test platform at hand anymore. It is proven to run on my Macbook (Mojave) with Python 3.8.2 and Raspberry Pi 3 with Python 3.7.3 and pip3.
• tested with PlantUML library v1.2022.6 (via the PyCharm Plugin "PlantUML integration" version 5.16.1)
• needs at least the PlantUML v1.2022.2, as now use of the %splitstr() preprocessor feature is made that was introduced then

pumla Architecture

The pumla Architecture is also documented using pumla.

Here is a first rough overview:

Link to pumla architecture documentation

pumla Roadmap

See here:

Link to pumla wiki with roadmap

pumla Test Strategy

Here is a rough description of the test strategy:

Link to pumla test strategy document

Development Note

Original pumla source code developed by Dr. Markus Voss 2021 - 2024.

Original pumla repository: https://github.com/DrMarkusVoss/pumla

Enjoy.