Interface Guidance and Opinions Needed

Hello to all,

This is my first time posting to this forum and I am very new to PostgreSQL.  I am very excited about using it.  I have set up a database and just need a point in the right direction on interfacing.   I have an orders and messages database.  One of the providers I would like to interface with has sent me an XML spec to make HTTPS posts to.  I am just wondering what would be the easiest thing to use to implement the two.  I would like to scan my database for new orders then do an HTTPS post to the provider.  I would also like to periodically check for new orders/messages from the provider via an HTTPS post and bring them into my database (a constant exchange of information).  I am wondering if something like PHP would be a universal solution, or something similar?

Sorry if the information I have given is basic, I have been doing research on the internet trying to figure out which direction to go and starting off is a little overwhelming.

Thanks in advance for any information

Chris Golden