Connection problems (Docker images) with PHP 7.3 using PDO and Postgres - docker

Question

I was changing my development environment from an old XAMPP installation to a new dockerized solution (OS: Ubuntu Mate LTS 18.03). It seems everything is running fine, but I still don’t get a connection from the Apache2 docker image to my Postgres DBMS docker image. :-/
I use the official postgres docker image with the Postgres 10.3 Server. The Database is up and I can connect via my NetBeans 11 IDE, also via the PgAdmin tool and a local running JavaEE Tomcat Server. The Server also accept connections outside of localhost. The command to initiate the postgres image was:
docker run -d -p 5432:5432 --name postgres -v /media/veracrypt1/Applications/docker/postgreSQL:/var/lib/postgresql/data postgres
As Apache /PHP image I use also the official php7.3-apache from DockerHub. The Image I instantiated by:
docker run -d -p 80:80 --name php-7.3 -v /media/veracrypt1/htdocs:/var/www/html -v /media/veracrypt1/Applications/docker/php-7.3/apache:/etc/apache2 -v /media/veracrypt1/Applications/docker/php-7.3/php:/usr/local/etc/php php:7.3-apache
The PHP scripts also get well executed.
Then I find out with the php_info() the Apache image do not contain the postgres pdo extension. I added the extensions inside the docker image by a solution I had find on google:
apt-get install -y libpq-dev \
&& docker-php-ext-configure pgsql -with-pgsql=/usr/local/pgsql \
&& docker-php-ext-install pdo pdo_pgsql pgsql
After this procedure the postgres PDO extension appear in the php_info() and by the command \PDO::getAvailableDrivers(). But when I try to connect I still get a server timeout:
[ERROR] DBMS Connection SQLSTATE[08006] [7] timeout expired
As Driver output is got this information: available Drivers: array(2) { [0]=> string(6) "sqlite" 2=> string(5) "pgsql" }
My php snippet seems also fine:
$dsn = sprintf("pgsql:host=%s;port=%d;dbname=%s;user=%s;password=%s",
$params[$this->host],
$params[$this->port],
$params[$this->schemata],
$params[$this->user],
$params[$this->password]);
$ dbh = new \PDO($dsn $this->user, $this->password);
$dbh->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
$dbh->setAttribute(\PDO::ATTR_TIMEOUT, 10);
$pdo = $dbh->query($sql);
The database table is available and the SELECT statement works fine inside the NetBeans IDE.
It looks that there is an issue with the php7.3-apache image. I guess my way to activate the extension is not proper. If someone could help me to get the DBMS connection would be great. Thanks a lot in advanced.
EDIT: The full POD Connection string is:
pgsql:host=172.17.0.1;port=5432;dbname=tinycms;user=tinycms;password=tinycms
Database User etc is correct, because I us this in my Netbeans IDE to connect to postgres.
CMD of the postgres docker container (including the execution of the PHP script:
jean#jean-ThinkPad-T540p:~$ docker start -a postgres
2019-07-13 16:19:20.680 UTC [1] LOG: listening on IPv4 address "0.0.0.0", port 5432
2019-07-13 16:19:20.680 UTC [1] LOG: listening on IPv6 address "::", port 5432
2019-07-13 16:19:20.848 UTC [1] LOG: listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
2019-07-13 16:19:21.446 UTC [26] LOG: database system was shut down at
2019-07-13 16:18:45 UTC
2019-07-13 16:19:21.637 UTC [1] LOG: database system is ready to accept connections