Run Scripts with strftime to make day-specific environments from a template file.

rundayenv.sh

#!/bin/bash

POSITIONAL_ARGS=()
PREFIX="ENV"
while [[ $# -gt 0 ]]; do
  case $1 in
    -h|--help)
      echo "Usage"
      echo "-----"
      echo "    $0 [--prefix=PREFIX] TEMPLATE_ENV STARTDAY [ENDDAY [SCRIPT]]"
      echo ""
      echo "  PREFIX       : Environments output as PREFIX_DAY.env. Defaults to ENV"
      echo "  TEMPLATE_ENV : file with environment variables on individual lines"
      echo "  STARTDAY     : Day to start making day specific environments"
      echo "  ENDDAY       : Optional day to end (defaults to STARTDAY)"
      echo "  SCRIPT       : Script to run with environment in Optional day to end (defaults to STARTDAY)"
      echo ""
      echo "Example"
      echo "-------"
      echo "This example uses strftime to copy a single template environment and make"
      echo "it day-specific. A simple example is shown below and assumes that temp.env"
      echo "and temp.sh exist as show below. temp.sh must be executable."
      echo ""
      echo "  > cat temp.env"
      echo "  GR_EMIS_001=\"a/%Y-%m-%d.nc\""
      echo "  GR_EMIS_003=\"b/%Y-%m-%d.nc\""
      echo "  GR_EMIS_002=\"c/%Y-%m-%d.nc\""
      echo ""
      echo "  > cat temp.sh"
      echo "  echo \$GR_EMIS_001"
      echo "  echo \$GR_EMIS_002"
      echo "  echo \$GR_EMIS_003"
      echo ""
      echo "  # Run temp.sh with each day specific"
      echo "  > $0 temp.env 2022-01-01 2022-01-02 temp.sh"
      echo ""
      echo "  Or create a day-specific environment, load and run"
      echo ""
      echo "  > $0 --prefix=EX temp.env 2022-01-01"
      echo "  # Set environmental variables from file"
      echo "  > export \$(cat EX_2022-01-01.env | xargs)"
      echo "  # Run an script in updated environment"
      echo "  > bash temp.sh # inherit"
      exit 1
      ;;
    -p=*|--prefix=*)
      PREFIX="$2"
      shift # past argument=value
      shift # past argument=value
      ;;
    -*|--*)
      echo "Unknown option $1"
      exit 1
      ;;
    *)
      POSITIONAL_ARGS+=("$1") # save positional arg
      shift # past argument
      ;;
  esac
done

# Restore positional arguments
set -- "${POSITIONAL_ARGS[@]}"

if [ $# -lt 2 ]; then
    echo "Expected 2 or 3 positional arguments. Run $0 --help for more details."
    exit 1
fi

# Assign positional arguments to meaningful names
TMPLENV=$1
STARTDAY=`date -d "${2}" +%Y-%m-%d`
if [ $# -lt 3 ]; then
  ENDDAY=`date -d "${2}" +%Y-%m-%d`
else:
  ENDDAY=`date -d "${3}" +%Y-%m-%d`
fi
if [ $# -gt 3 ]; then
  SCRIPT=$4
  HAS_SCRIPT=Y
else
  HAS_SCRIPT=N
fi

# Loop over all days creating copies of the environment
DAY=${STARTDAY}
until [[ "${DAY}" > "2022-01-02" ]]; do
  penv=${PREFIX}_${DAY}.env
  if [ ! -e $penv ]; then
    echo "Making ${penv}"
    printf "" > $penv
    cat $TMPLENV | while read line; do
      date -d "$DAY" +$line >> $penv
    done
  else
    echo "Keeping cached $penv"
  fi
  # If a script is provided, load the environment and run the script
  if [ ${HAS_SCRIPT} == "Y" ]; then
    export $(cat $penv | xargs)
    $SCRIPT
  fi
  DAY=`date -d "${DAY} +1day" +%Y-%m-%d`
done