digraph A {
    rankdir=LR;
    ranksep=0.5;
    cgiserver [fontname=Terminal,shape=box];
    session [fontname=Terminal,shape=polygon,orientation=45,label="session\nmiddleware"];
    urlparser [fontname=Terminal,shape=polygon,orientation=45,label="urlparser\nmiddleware"];
    index [fontname=Terminal, label=".../index.py"];
    view [fontname=Terminal, label=".../view.py"];
    login [fontname=Terminal, label=".../login.py"];
    cgiserver -> session [headlabel=1,color=green,labelfontcolor=black,labeldistance=1.2];
    session -> urlparser [headlabel=2,color=green,labelfontcolor=black,labeldistance=1.2];
    urlparser -> index [headlabel=3,color=green,labelfontcolor=black,labeldistance=1.2];
    urlparser -> view [headlabel=3,color=green,labelfontcolor=black,labeldistance=1.2];
    urlparser -> login [headlabel=3,color=green,labelfontcolor=black,labeldistance=1.2];

    session -> cgiserver [headlabel=6,color=red,labelfontcolor=black,labeldistance=1.2];
    urlparser -> session [headlabel=5,color=red,labelfontcolor=black,labeldistance=1.2];
    index -> urlparser [headlabel=4,color=red,labelfontcolor=black,labeldistance=1.2];
    view -> urlparser [headlabel=4,color=red,labelfontcolor=black,labeldistance=1.2];
    login -> urlparser [headlabel=4,color=red,labelfontcolor=black,labeldistance=1.2];
}