PHP script to display Postgres DB's and schemata

<?php
/**
 * Live Overview Databases and Schemata for Postgresql
 *
 * Shows all registered databases and if applicable their schemes
 * @author: planzelle
 *
 */

// init (hosts to display)
$hosts = array('f1-db1.sys.de', 'f1-db2.sys.de');

// NO CHANGES BEYOND THIS POINT ! (user: postgres, no password)

// get handle for postgres internal system db
function getPgHandle($host) {
    $dsn = sprintf("pgsql: host=%s dbname=postgres", $host);
    $dbh = new PDO($dsn, 'postgres', '') or die('No connection to host: '.$host);
    return $dbh;
}


// get handle for db
function getDbHandle($host, $dbname) {
    $dsn = sprintf("pgsql: host=%s dbname=%s", $host, $dbname);
    $dbh = new PDO($dsn, 'postgres', '') or die('No connection to host: '.$host);
    return $dbh;
}


// filter only non-system dbs and those who are not test/demo or templ
function filterDatname($name) {
    $ret = strpos($name, 'etacs_')===0? true : false;
    if (preg_match('/(test|demo|_templ)/',$name)) {
        $ret = false;
    }
    return $ret;
}

// filte allowed schema
function filterSchema($name) {
    $ret = true;
    if (preg_match('/(public|information_schema|pg_)/', $name)) {
        $ret = false;
    }
    return $ret;
}


function printHeader() {
    echo <<<EOH
<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>Etacs DB Explorer</title>
    <style>
        .grey { color: grey;}
        .blue { color: blue;}
        .red { color: red;}
        body { font-family: courier;}
        td { padding: 5px;}
    </style>
</head>
<body>

EOH;
}


function printContent($arr) {
    $cnt = 0;
    printf('<table><tbody><tr valign="top">%s',"\n");
    foreach($arr as $server) {
        $host = $server['name'];
        printf('<td><table border="1"><tr><th><h4 class="blue">%s</h4></th></tr>%s', $host, "\n");
        foreach ($server['databases'] as $databases) {
            $database = $databases['name'];
            if (empty($arr[$host]['databases'][$database]['schema'])) {
                // no schemas, so print and count the database
                printf("<tr><td>%s. %s</td></tr>\n", ++$cnt, $database);
            } else {
                // schema dbs, so print, but don't count databases and list schemata
                printf('<tr><td><em><strong class="grey">Schema-DB:</strong> <span class="red">%s</span></em><br />%s', $database, "\n");
                foreach($arr[$host]['databases'][$database]['schema'] as $schema) {
                    printf("%s. %s<br />\n", ++$cnt, $schema);
                }
                print("</td></tr>\n");
            }
        }
        echo "</table></td>";
    }
    echo "</tr></tbody></table>\n";
}


function printFooter() {
    echo <<<EOF

</body>
</html>
EOF;
}


$arr = array();
printHeader();
// main loop
foreach($hosts as $host) {
    $arr[$host] = array('name'=>$host, 'databases'=>array());
    $db1 = getPgHandle($host);
    $sql1 = "SELECT datname FROM pg_database ORDER BY datname;";
    $stmt1 = $db1->query($sql1);
    if ($stmt1) {
        while($row = $stmt1->fetch(PDO::FETCH_ASSOC)) {
            $dbname = $row['datname'];
            if (filterDatname($dbname)) {
                $arr[$host]['databases'][$dbname] = array('name'=>$dbname, 'schema'=>array());
                $db2 = getDbHandle($host, $dbname);
                $sql2 = sprintf("SELECT schema_name FROM information_schema.schemata WHERE catalog_name='%s' ORDER BY schema_name;", $dbname);
                $stmt2 = $db2->query($sql2);
                if ($stmt2) {
                    while($row2 = $stmt2->fetch(PDO::FETCH_ASSOC)) {
                        $schema = $row2['schema_name'];
                        //echo $schema;
                        if (filterSchema($schema)) {
                            $arr[$host]['databases'][$dbname]['schema'][] = $schema;
                        }
                    }
                }
            }
        }
    }
}
printContent($arr);
printFooter();