我已经设置了mod_auth_mellon来保护网络应用。我已将其设置为针对外部IdP（Okta）进行身份验证。我想打印出Okta在身份验证后发送的属性列表。虽然我已经设置了要在Okta中发送的变量，但我无法在任何会话变量中接收属性。我可以使用SAML Tracer查看值。我对mod_auth_mellon的配置如下：
MellonEnable "auth"
MellonSetEnv "email" "email"
MellonSetEnv "username" "username"
我正在尝试通过打印 $ _ SESSION 变量来读取ACS URL中的值。我得到的回应如下：
HTTP_HOST=54.86.69.246 HTTP_CONNECTION=keep-alive CONTENT_LENGTH=10734 HTTP_CACHE_CONTROL=max-age=0 HTTP_ACCEPT=text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 HTTP_ORIGIN=null HTTP_UPGRADE_INSECURE_REQUESTS=1 HTTP_USER_AGENT=Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.93 Safari/537.36 CONTENT_TYPE=application/x-www-form-urlencoded HTTP_ACCEPT_ENCODING=gzip, deflate HTTP_ACCEPT_LANGUAGE=en-US,en;q=0.8 HTTP_COOKIE=mellon-cookie=cookietest PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin SERVER_SIGNATURE=
Apache/2.4.7 (Ubuntu) Server at 54.86.69.246 Port 80
SERVER_SOFTWARE=Apache/2.4.7 (Ubuntu) SERVER_NAME=54.86.69.246 SERVER_ADDR=172.31.34.194 SERVER_PORT=80 REMOTE_ADDR=123.201.163.97 DOCUMENT_ROOT=/var/www/html REQUEST_SCHEME=http CONTEXT_PREFIX= CONTEXT_DOCUMENT_ROOT=/var/www/html SERVER_ADMIN=webmaster@localhost SCRIPT_FILENAME=/var/www/html/info.php REMOTE_PORT=49613 GATEWAY_INTERFACE=CGI/1.1 SERVER_PROTOCOL=HTTP/1.1 REQUEST_METHOD=POST QUERY_STRING= REQUEST_URI=/info.php SCRIPT_NAME=/info.php PHP_SELF=/info.php REQUEST_TIME_FLOAT=1442839622.177 REQUEST_TIME=1442839622
我该怎么做才能阅读这些数据？