[Error] pg_config executable not found.

배경

redshift 실습을 위해 psycopg2 모듈을 커맨드로 설치하던 중 발생

pip install psycopg2

Collecting psycopg2
  Downloading psycopg2-2.9.3.tar.gz (380 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 380.6/380.6 kB 6.7 MB/s eta 0:00:00
  Preparing metadata (setup.py) ... error
  error: subprocess-exited-with-error

  × python setup.py egg_info did not run successfully.
  │ exit code: 1
  ╰─> [20 lines of output]
      running egg_info
      creating /private/var/folders/ql/sxpb0jls2ks5nz5_7tw7rggm0000gn/T/pip-pip-egg-info-xie4l2ci/psycopg2.egg-info
      writing manifest file '/private/var/folders/ql/sxpb0jls2ks5nz5_7tw7rggm0000gn/T/pip-pip-egg-info-xie4l2ci/psycopg2.egg-info/SOURCES.txt'

      Error: pg_config executable not found.

      pg_config is required to build psycopg2 from source.  Please add the directory
      containing pg_config to the $PATH or specify the full executable path with the
      option:

          python setup.py build_ext --pg-config /path/to/pg_config build ...

      or with the pg_config option in 'setup.cfg'.

      If you prefer to avoid building psycopg2 from source, please install the PyPI
      'psycopg2-binary' package instead.

      For further information please check the 'doc/src/install.rst' file (also at
      <https://www.psycopg.org/docs/install.html>).

      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

원인

• • Postgresql 설치가 안되어 pg_config 가 미 생성됨
    • which pg_config 조회 결과 없음
    • pg_config : 설치된 Postgresql 버전의 정보(매개변수)가 있는 도구

해결

• Postgresql 설치

  • (MAC) brew install postgresql

  • 가상환경일 경우

    • 환경변수 등록
      • wtich pg_config 참조하여 경로 복사
      • export PATH=$PATH:{pg_config path}
      • 참고

  • 프로덕션에서 사용하지 않는다면 psycopg2-binary 고려

    • pip install psycopg2-binary
    • 참고