How to install libpq-fe.h?

Question

I cannot figure this out for the life of me.

When I pip install django-tenant-schemas it tries to install the dependency psycopg2 which req

Answer 1

you need to create a LD_LIBRARY_PATH where indicates the path of your library "/user/pgsql-11/lib"

The third point of build prerequisites http://initd.org/psycopg/docs/install.html

Answer 2

For some reason, the file is missing on the system.

As you're using apt-get, the system is dpkg based, presumably Debian or it's derivative. You can try the Ubuntu's package search to get which package contains a file with name ending in libpq-fe.h.

I found the package is libpq-dev and file's absolute path is /usr/include/postgresql/libpq-fe.h.

---

FWIW, on a dpkg based system, you can check which package gives a file if you know the file's absolute path:

% dpkg -S /usr/include/postgresql/libpq-fe.h
libpq-dev: /usr/include/postgresql/libpq-fe.h

Also, unlike find, locate keeps a cache of found files (mlocate.db) that is created everyday via cron; so if the file happens to be removed after the last run, you can run locate libfq-fe.h to get the absolute path to the file without needing to check the Ubuntu package search online.

---

So the package is libpq-dev. Now, reinstalling it will get everything to the default state i.e. all relevant files will be copied to the right places. As it is only a library package, no user/system level configurations will be overridden (and dpkg will prompt you for action for any package that does that).

To reinstall the package:

sudo apt-get install --reinstall libpq-dev

Answer 3

Well after installing these libraries sudo dnf install python-virtualenv openssl-devel gcc libffi-devel libxslt-devel issue did not gone.

I used mlocate to find where libpq-fe.h file is located. On my system (Fedora 32) it was located at /usr/pgsql-10/include/libpq-fe.h

yum install mlocate
sudo updateb
locate libpq-fe.h

After all added this line to ~/.bash_profile

nano ~/.bash_profile
export PATH=/usr/pgsql-10/bin/:$PATH

Works fine, I can easily install psycopg2 without any trouble.