Drawing diagrams
C4
Using graphviz
Graphviz is a powerful open source graph visualization tool written in (mostly) C that allows you
to define graphs using the dot language.
I did not find any good pre-defined templates for making C4 diagrams using Graphviz so I have written my own. As I have also made a bunch of other diagrams in this course using the dot language I wanted to keep the graphing language consistent. You can have a look at one example here:
Example c4 container diagram made in the dot language
digraph iterative{
rankdir="TB";
dpi=300;
edge [ style=dashed ];
node[
shape = rect
style = "filled, rounded"
color = "#a4fad0"
];
user [
label=<
<table border="0" cellborder="0">
<tr> <td><b>Scientist</b></td> </tr>
<tr> <td>[Person]</td> </tr>
<tr> <td>A researcher using the tool</td> </tr>
</table>
>
]
node[
shape = rect
style = filled
fillcolor = "#9db5f7"
color = "black"
];
subgraph cluster_software {
label=<<b>Solar-system simulation</b>>
cli [
label=<
<table border="0" cellborder="0">
<tr> <td><b>Simulation CLI interface</b></td> </tr>
<tr> <td>[Container: Python]</td> </tr>
<tr> <td>The interface for configuring and\nrunning the simulations</td> </tr>
</table>
>
]
lib [
label=<
<table border="0" cellborder="0">
<tr> <td><b>Simulation library</b></td> </tr>
<tr> <td>[Container: C]</td> </tr>
<tr> <td>The simulation software that solves\nthe equations of motion</td> </tr>
</table>
>
]
vis [
label=<
<table border="0" cellborder="0">
<tr> <td><b>Visualization tool</b></td> </tr>
<tr> <td>[Container: Odin]</td> </tr>
<tr> <td>A tool to create 3d visualizations\nof the simulation results</td> </tr>
</table>
>
]
storage [
shape = cylinder
label=<
<table border="0" cellborder="0">
<tr> <td><b>Results</b></td> </tr>
<tr> <td>[Container: Filesystem and HDF5]</td> </tr>
<tr> <td>The simulation results stored on\na file system using HDF5</td> </tr>
</table>
>
]
}
node[
shape = rect
style = filled
fillcolor = "#cfcfcf"
color = "black"
];
horizons [
label=<
<table border="0" cellborder="0">
<tr> <td><b>JPL Horizons System</b></td> </tr>
<tr> <td>[Software system]</td> </tr>
<tr> <td>A software system to calculate positions<br/>and velocities of solar system bodies at a requested time</td> </tr>
</table>
>
]
user -> cli [label="Configures and\nsimulates scenarios\n[SSH]"]
cli -> horizons [label="Gets the solar-system\nbody states for scenario\n[JSON/HTTPS]"]
cli -> lib [label="Configures and calls functions"]
cli -> vis [label="Configures and runs"]
lib -> storage [label="Reads from \nand writes to"]
vis -> storage [label="Reads from"]
user -> vis [label="Views results\n[RTSP stream]"]
}
The above code generates this figure:
Using plantUML
PlantUML is a Java tool for drawing a wide range of diagrams, notably Unified Modeling Language (UML) and similar diagrams.
There is a predefined set for drawing specifically C4-architecture diagrams called C4-PlantUML that you can include into your PlantUML files by
!include <C4/C4_Container>
To read more on how to use C4-PlantUML, see the github README.md.
Other tooling
There is an extensive list of other tooling for C4 listen on c4model.com’s tooling page.
State diagrams
A state diagram is fairly simple to draw. If we follow the UML definition we can draw them using the plantUML’s state-diagram or any other UML diagram drawing tool.
Using graphviz
My own recipe for drawing state-diagrams using graphviz is:
digraph finite_state_machine {
label="Pressure valve";
rankdir="LR";
dpi=300;
node [shape=point, label=""];
ENTRY;
EXIT;
node [shape=rect, style=rounded];
A[label="Low flow"];
B[label="High flow"];
C[label="No flow"];
ENTRY->A [label="Start"];
A->C [label="Shutdown"];
B->A [label="Pressure drops"];
A->B [label="Request recived"];
C->EXIT [label="End"];
}
Which results in
