[Django]-Can't install psycopg2 with pip in virtualenv on Mac OS X 10.7

Just would like to share. The following code worked for me:

env LDFLAGS='-L/usr/local/lib -L/usr/local/opt/openssl/lib
-L/usr/local/opt/readline/lib' pip install psycopg2==2.5.2

I am using macOS Sierra and psql 9.6.1.

I got the lib path from the pg_config command.

I am using MAC OS CATALINA verison 10.15.5 with python3 and psql (PostgreSQL) 12.3. Here is what worked for me:

Try installing openssl using brew

brew install openssl

after that export these variables in the terminal.

export LDFLAGS="-L/usr/local/opt/openssl/lib"
export CPPFLAGS="-I/usr/local/opt/openssl/include"

verify these variables have been exported by echo $LDFLAGS and after that you are good to go with installation of psycopg2 by typing

pip3 install psycopg2

First, download Postgres.app.

Then, before running pip install psycopg2, put the binary in your path:

export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.3/bin

NOTICE:

9.3 stands for version and will differ over time.

Generic LDFLAGS variable set

Just export LDFLAGS before installing it, here is generic command which shall work for OS X (and I believe any LINUX system which has same error):

 LDFLAGS="$(pg_config --ldflags)" pip install psycopg2

The workaround is to intsall ‘psycopg2-binary’ package

Install postgres with brew:

brew install postgres

Then, in your virtualenv install psycopg2 with this command:

ARCHFLAGS=-Wno-error=unused-command-line-argument-hard-error-in-future pip install psycopg2

Focusing on this line: ld: library not found for -lpq

psycopg2, like most 3rd-party postgres libraries, wants ‘pg_config’ available in your path. I’m guessing that’s your problem.

Type ‘pg_config’ at the command prompt. I hope you see that it’s not found. If not, do a:

sudo find / -name pg_config

to find where it’s at, and then add that location to your path, run ‘pg_config’ and see it succeed, and then finally, re-run pip.

the find command is searching starting at your root dir; it will take a few minutes.

I was trying so many things and nothing worked. However, if you use Xcode CLI Tools on Mojave and have a problem installing psycopg2, try the following command and try to install psycopg2 again.

sudo installer -pkg /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg -target /

This was described as a Mojave Issue: Pillowissue

In my case, this solved the issue.

Try this:

pip install psycopg2-binary

First this:
pip install psycopg2-binary
and then:
pip install psycopg2 worked.

The following post helped me get it working:

https://stackoverflow.com/a/10326004/1361851

Had to install “command line tools” for Xcode and then I was able to pip install with the virtualenv just the same as the heroku tutorial.

I tried all of the above solutions but the only thing that resolved the issue for me is simply updating Xcode CLI utilities through the official App Store.

Once I was also facing the same problem on Mac then I figured out that psycopg2 has a dependency on GCC library.

export LDFLAGS="-L/usr/local/opt/openssl/lib"

export CPPFLAGS="-I/usr/local/opt/openssl/include"

Just run this command and then try to run

pip install psycopg2

Hope this will work.