Hello,
I am developing a Google API that will be accessible on a Wordpress site.
I have been working on Wordpress for a long, but I never had the need to pre-develop on a Google Cloud Service.
So it’s my first time with Google Cloud 
.
I have created a project in Google Cloud, I have downloaded all files from my Wordpress live server (all files and credentials are correct), and I haved uploaded them via Cloud Shell.
I have also created a MySQL database wich is connected to the correct instance (my project id).
Yet, when I click on Web Preview, en error message says : Error establishing a database connection.
I guess there is a problem with credentials, here is what I did :
After I created a DB on Google Cloud, I opened my wp-config.php to change the old DB name and password, as wp-config.php was containing the credentials for the DB that is actually on the live site.
Here is the part of wo-config.php where I changed the credentials :
/** The name of the database for WordPress : I changed it to the name for the newly created DB */
define( ‘DB_NAME’, ‘new_name’ );
/** Database username I didn’t change the user name*/
define( ‘DB_USER’, ‘old_user_name’ );
/** Database password I changed the password*/
define( ‘DB_PASSWORD’, 'XXXXX );
However, I didn’t input the new Data base User name, could it be the reason why I can’t connect to the Data base ? If so, where can I find my Google Data base user name ?
Morover, I navigated to My SQL On Google Cloud, I clicked “To connect using Gcloud Open Cloud Shell”. It indeed open Cloud Shell and generated a cmd that says :
xxx@cloudshell:~ (my-project-id)$ gcloud sql connect database_name --user=root --quiet
However, when I click on Web Preview, I still see : error establishing a database connection.
Can anyone tell me what I did wrong ?
Thank you very much in advance.