QGIS » QGIS Application

I have configured a localhost qgiserver/qgisclient in my windows 10 pc with Apache/2.4.27 (Win64) and php7 loaded in httpd.conf:

LoadModule php7_module "C:\Apache_qgiserver\php_mod\php7apache2_4.dll"
AddHandler php7-script php
DirectoryIndex index.html index.php
AddType text/html php
PhpIniDir "C:\Apache_qgiserver\php_mod"

The Web client works fine but I cannot configure php search box... I've created a sample project named "prova.qgs" in \htdocs\QGIS-Web-Client\projects with a postgis layer inside named "italia". Then I modified GlobalOptions.js to include search box:
// PHP based search scripts (postgis layers only)
var searchBoxQueryURL = '../php/search.php?map=' + project_map;
var searchBoxGetGeomURL = '../php/search_geom.php?map=' + project_map;

Then I set up the config.php file as follows:

/************************************** * search configuration
*/
// Configuration for searchable layers
$searchlayers_config = array(
// Key is layer name
'italia' => array(
// SQL for text search: where to search
'search_column' => 'nome'
)
);

// Default search tables
define('DEFAULT_SEARCH_LAYERS', 'italia');

but the search box doesn't work and I receive an error:

Internal server error (QGIS Client)
db error: SQLSTATE⁰⁸⁰⁰⁶ [7] FATALE: autenticazione con password fallita per l'utente "'postgres'"

this is the query url: http://localhost/php/search.php?map=C:/Apache_qgiserver/htdocs/QGIS-Web-Client/projects/prova.qgs&searchtables=&query=sicilia&cb=stcCallback1001