Install postgis with postgresql@12 for macOS

install_postgis.sh

#!/bin/bash

TMP_DIR="./tmp"
mkdir -p $TMP_DIR

function install_sfcgal() {
  SFCGAL_FORMULAE_PATH="$TMP_DIR/sfcgal.rb"
  DOWNLOAD_URL="https://gist.githubusercontent.com/sfate/cc92b94657ed4fcf3b35b17849e4d65a/raw/69db8b4c9401c8914babf854af5512ab4f897e19/sfcgal.rb"

  curl -s $DOWNLOAD_URL -o "$SFCGAL_FORMULAE_PATH"
  
  # installed patched formulae for apple silicon chip (M1)
  brew install --formula $SFCGAL_FORMULAE_PATH
}

function install_postgis() {  
  POSTGIS_VERSION='postgis-3.0.3'
  POSTGIS_ARCHIVE="$POSTGIS_VERSION.tar.gz"
  POSTGIS_ARCHIVE_PATH="$TMP_DIR/$POSTGIS_ARCHIVE"
  DOWNLOAD_URL="https://download.osgeo.org/postgis/source/$POSTGIS_ARCHIVE"

  # download suitable archive (v3.0.3) for postgres@12
  curl -s $DOWNLOAD_URL -o $POSTGIS_ARCHIVE_PATH

  # unpack archive
  cd $TMP_DIR
  tar xzf $POSTGIS_ARCHIVE

  cd "$TMP_DIR/$POSTGIS_VERSION"

  # install dependencies
  install_sfcgal
  brew install 'gdal'
  brew install 'geos'
  brew install 'json-c'
  brew install 'pcre'
  brew install 'proj@7'
  brew install 'protobuf-c'

  # generate Makefile
  # --prefix parameter is currently broken, as the package will only install into the PostgreSQL installation directory.
  # Visit http://trac.osgeo.org/postgis/ticket/635 to track this bug.
  ./configure \
    --disable-nls \
    --with-pgconfig=$(brew --prefix postgresql@12)/bin/pg_config \
    --with-sfcgal=$(brew --prefix sfcgal)/bin/sfcgal-config \
    --with-gdalconfig=$(brew --prefix gdal)/bin/gdal-config \
    --with-geosconfig=$(brew --prefix geos)/bin/geos-config \
    --with-jsondir=$(brew --prefix json-c) \
    --with-pcredir=$(brew --prefix pcre) \
    --with-projdir=$(brew --prefix proj@7) \
    --with-protobufdir=$(brew --prefix protobuf-c)

  # link header files for build
  ln -s "$(brew --prefix postgresql@12)/include/postgresql/server" "$(brew --prefix postgresql@12)/include/server"

  # build source code from Makefile
  make

  # copy installation files into appropriate subdirectory
  make install
}

brew install postgresql@12

# load posgresql@12 cli functions into environment
echo 'PATH="$(brew --prefix postgresql@12)/bin:$PATH"' >> ~/.bashrc
brew services start postgresql@12

install_postgis