pod.tex

\documentclass{article}
\usepackage{tikz}
\usepackage[graphics,tightpage,active]{preview}
\usetikzlibrary{arrows, shadows.blur, positioning, fit, calc, backgrounds}
\usepackage{lscape}

\pagenumbering{gobble}

\PreviewEnvironment{tikzpicture}
\PreviewEnvironment{equation}
\PreviewEnvironment{equation*}
\newlength{\imagewidth}
\newlength{\imagescale}
\pagestyle{empty}
\thispagestyle{empty}

\begin{document}
\begin{center}
\begin{tikzpicture}[
  scale=0.5,transform shape,
  font=\sffamily,
  every matrix/.style={ampersand replacement=\&,column sep=2cm,row sep=2cm},
  pod/.style={draw,solid,thick,circle,fill=red!20,inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  component/.style={draw,solid,thick,rounded corners,fill=yellow!20,inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  border/.style={draw,dashed,rounded corners,fill=gray!20,inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  volume/.style={draw,solid,thick,rounded corners,fill=blue!20, inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  sidecar/.style={draw,solid,thick,rounded corners,fill=blue!20, inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  k8s-label/.style={draw,solid,thick,rounded corners,fill=blue!20, minimum width=1.5cm, inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  affinity/.style={draw,solid,thick,rounded corners,fill=blue!20, minimum width=2cm, inner sep=.3cm, blur shadow={shadow blur steps=5,shadow blur extra rounding=1.3pt}},
  label/.style={rectangle,inner sep=0,outer sep=0},
  to/.style={->,>=stealth',shorten >=1pt,semithick,font=\sffamily\footnotesize},
  every node/.style={align=center}]

  % Position the nodes using a matrix layout

  \matrix{
    \path
      node[k8s-label] (app-label) {App}
      node[k8s-label, right=.25cm of app-label] (role-label) {Role}
      node[k8s-label, right=.25cm of role-label] (custom-label) {Custom}
      node[label, below of=role-label] (k8s-label-label) {K8s Labels}
      node[border, behind path,
           fit=(app-label)(role-label)(custom-label)(k8s-label-label)
      ] (k8s-labels) {};  \& \&
    \path
      node[affinity] (affinity) {Affinity}
      node[label, right=.25cm of affinity] (affinity-middle) {}
      node[affinity, right=.25cm of affinity-middle] (anti-affinity) {Anti-affinity}
      node[label, below of=affinity-middle] (affinity-label) {Assigning to nodes}
      node[border, behind path,
           fit=(affinity)(anti-affinity)(affinity-label)
      ] (affinity) {}; \\
    \& \node[pod] (pod) {Pod}; \& \\
    \path
      node[volume, minimum width={width("shm-volume")}] (data-volume) {Data}
      node[volume, right=.25cm of data-volume, minimum width={width("shm-volume")}] (tokens-volume) {Tokens}
      node[volume, right=.25cm of tokens-volume] (shm-volume) {/dev/shm}
      node[label, below of=tokens-volume] (volumes-label) {Volumes}
      node[border, behind path,
           fit=(data-volume)(shm-volume)(tokens-volume)(volumes-label)
      ] (volumes) {}; \&
    \node[component] (spilo) {Spilo}; \&
    \node[sidecar] (scalyr) {Scalyr}; \& \\ \&
    \path
      node[component] (patroni) {Patroni}
      node[component, below=.25cm of patroni] (postgres) {PostgreSQL}
      node[border, behind path,
           fit=(postgres)(patroni)
      ] (spilo-components) {}; \&
    \path
      node[sidecar] (custom-sidecar1) {User defined}
      node[label, right=.25cm of custom-sidecar1] (sidecars-middle) {}
      node[sidecar, right=.25cm of sidecars-middle] (custom-sidecar2) {User defined}
      node[label, below of=sidecars-middle] (sidecars-label) {Custom sidecars}
      node[border, behind path,
           fit=(custom-sidecar1)(custom-sidecar2)(sidecars-label)
      ] (sidecars) {};
    \\ \& \\
  };

  % Draw the arrows between the nodes and label them.
  \draw[to] (pod) to [bend left=25] (volumes);
  \draw[to] (pod) to [bend left=25] (k8s-labels);
  \draw[to] (pod) to [bend right=25] (affinity);
  \draw[to] (pod) to [bend right=25] (scalyr);
  \draw[to] (pod) to [bend right=25] (sidecars);
  \draw[to] (pod) -- node[midway,above] {} node[midway,below] {} (spilo);
  \draw[to] (spilo) -- node[midway,above] {} node[midway,below] {} (spilo-components);

\end{tikzpicture}
\end{center}
\end{document}