copy file from a client app to remote postgres isntance

Hi all,
I have an application that must copy a local file in csv format to a
postgres table on a remote host. The closest solution is this one (https://
stackoverflow.com/a/9327519/618020). It boils down to specifying a \copy
meta-command in a psql command:

psql -U %s -p %s -d %s -f - <<EOT\n here hoes a \copy meta-command \nEOT\n

and executing it. But it's quite an unnatural way to write database
code. Has anything changed in the last ten years? Or, is there a
better way to copy file contents in a remote database?