Simple Communication Diagram with LaTeX with a template structure

directory structure

.
├── fonts
│   └── Sauce Code Pro Nerd Font Complete.ttf
├── proposal
│   └── proposal-0001
│       └── readme.md
├── scripts
│   └── generate-tex
└── src
    ├── proposal
    │   └── proposal-0001
    │       └── flow.tex
    └── template.tex

./scripts/generate-tex

.
├── fonts
│   └── Sauce Code Pro Nerd Font Complete.ttf
├── proposal
│   └── proposal-0001
│       ├── assets
│       │   ├── flow-fill.png
│       │   └── flow.png
│       └── readme.md
├── scripts
│   └── generate-tex
└── src
    ├── proposal
    │   └── proposal-0001
    │       └── flow.tex
    └── template.tex

flow.tex

\begin{document}
\begin{tikzpicture}[
  draw=foreground, text=foreground,
  label/.style={pos=0.5,above,font=\tiny, sloped}
]
  \newcommand{\height}{5};

  \newcommand{\webui}{0};
  \newcommand{\gitops}{5};
  \newcommand{\mngc}{10};
  \newcommand{\leafca}{15};

  \layer{\webui}  {\height}   {Web UI};
  \layer{\gitops} {\height}   {Backe-end};
  \layer{\mngc}   {\height}   {Agent};
  \layer{\leafca} {\height}   {Cluster};

  \arrow{\webui}{\gitops}{4}{List all Releases}{label};
  \arrowstream{\gitops}{\webui}{1}{0.5}{Stream}{label};

  \arrow{\gitops}{\mngc}{3.5}{List all Releases} {label};

  \draw[dotted] (\mngc, 2.75) -- (7.5, 2.75);
  \draw[dotted] (7.5, 2.75) -- (7.5, 1)
    node [label, rotate=180] {Stream};
  \arrowstream{7.5}{\gitops}{1}{1}{}{};

  \arrow{\mngc}{\leafca}{3}
    {List all Releases}{label};

  \draw[dotted] (\mngc, 2.5) -- (7.5, 2.5);

  \arrowstream{\leafca}{\mngc}{2.5}{2.5}
    {List of events (Releases)}{label};

  \arrowstream{\leafca}{\mngc}{2}{2}
    {New events (Release)}{label};

  \arrowstream{\leafca}{\mngc}{1.5}{1.5}
    {New events (Release)}{label};

  \draw[dotted] (\mngc,2) -- (7.5, 2);
  \draw[dotted] (\mngc,1.5) -- (7.5, 1.5);

  % Add a bit of margin ;)
  \node[yshift=1em, xshift=-2em] at (0, \height) {};
  \node[yshift=-1em, xshift=2em] at (\leafca, 0) {};

\end{tikzpicture}
\end{document}

generate-tex

#!/usr/bin/env bash

scope="${1:-src}"
tmpDir=$(mktemp -d)
fontDir="$(git rev-parse --show-toplevel)/fonts/"

if [[ "${scope}" != src* ]]; then
  scope="src/${scope}"
fi

trap "rm -rf ${tmpDir}" EXIT

for file in $(find ${scope} -name "*.tex" -not -name 'template.tex'); do
  filePath=$(dirname $file | sed -e 's#^src/##')
  tmpPath="${tmpDir}/${filePath}"
  fileName="$(basename ${file} '.tex')"
  mkdir -p "${tmpPath}"

  echo -en " \U1F550 ${filePath}/${fileName}.tex ..."

  cat src/template.tex \
    | sed -e "s#@@TARGET@@#${file}#" \
          -e "s#@@FONTPATH@@#${fontDir}#" \
          -e "s#@@IMGPATH@@#$(pwd)/src/${filePath}/#" \
    | xelatex \
      -output-directory="${tmpPath}" \
      -jobname="${fileName}" \
      > /dev/null
  ret=$?

  if false; then
    if [ -n $ret ]; then
      echo ""
      cat "${tmpPath}/${fileName}.log"
      # exit
    fi
  fi

  convert \
    -density 300 \
    "${tmpPath}/${fileName}.pdf" \
    -quality 90 \
    "${tmpPath}/${fileName}.png"
  
  convert \
    -density 300 \
    "${tmpPath}/${fileName}.pdf" \
    -quality 90 \
    -background "#292a2d" \
    -flatten \
    "${tmpPath}/${fileName}-fill.png"

  mkdir -p "${filePath}/assets"
  cp "${tmpPath}/${fileName}.png" "${filePath}/assets/"
  cp "${tmpPath}/${fileName}-fill.png" "${filePath}/assets/"

  echo -e "\r \U2705 ${filePath}/${fileName}.tex -> ${filePath}/${fileName}[-fill].png"
done

template.tex

\documentclass{standalone}

\usepackage{tikz}
\usepackage{transparent}
\usepackage{fontspec}
\usepackage{xcolor}
\usepackage{graphicx}
\usepackage{anyfontsize}

\setmainfont{Umpush-Light.otf}
\setmonofont{Sauce Code Pro Nerd Font Complete.ttf}[
  Path = @@FONTPATH@@
]

\usetikzlibrary{calc, backgrounds, positioning, matrix}

\graphicspath{{@@IMGPATH@@}}

\newcommand{\layer}[3]{
  \node[draw] (top) at (#1, #2) {#3};
  \node[draw] (bottom) at (#1, 0) {#3};
  \draw (top.south) -| (bottom.north);
}

\newcommand{\arrow}[5]{
  \draw[-stealth] (#1, #3) -- (#2, #3) node [#5] {#4};
}

\newcommand{\arrowstream}[6]{
  \draw[-stealth, dotted] (#1, #3) -- (#2, #4) node [#6] {#5};
}

\definecolor{foreground}{RGB}{149, 149, 159}
\definecolor{background}{RGB}{41, 42, 45}

\input{@@TARGET@@}

Single file format: https://gist.github.com/yitsushi/ce4c6ef2bb749fc4bb77c5127ac90ca8