legend.dot

digraph {
  graph [layout = dot, splines = true, overlap = scale, ratio = 0.5]
  node [fontsize = 20]
  edge [fontsize = 10]
  rankdir=LR
  node [shape=plaintext]
  subgraph cluster_01 {
	style = rounded
    label = "Legend";
    fontsize = 20
    key [label=<<table border="0" cellpadding="2" cellspacing="0" cellborder="0">
      <tr><td align="right" port="i2">Events </td></tr>
      <tr><td align="right" port="i3">Commands </td></tr>
       <tr><td align="right" port="i1">Missing </td></tr>
     </table>>]
    key2 [label=<<table border="0" cellpadding="2" cellspacing="0" cellborder="0">
      <tr><td port="i2">&nbsp;</td></tr>
      <tr><td port="i3">&nbsp;</td></tr>
      <tr><td port="i1">&nbsp;</td></tr>
      </table>>]
    key:i2:e -> key2:i2:w [color=dimgrey]
    key:i3:e -> key2:i3:w [color=chocolate]
    key:i1:e -> key2:i1:w [color=red, style=dashed]
    node [shape=oval]
    Primary -> Secondary [style=invis] ;
    Primary [label = "Primary\nComponent", color = blue, fontcolor = blue, style = bold]
    Secondary [label = "Secondary\nComponent", style=dashed, color = blue] ;
    Missing [label = "Missing\nComponent", color=red, style=dashed] ;
  }
}