load-friction-raster

#!/bin/bash

set -euo pipefail

DATA_PATH=${DATA_PATH:-/data}
OUTPUT_PATH=${DATA_PATH}/friction/regions
export PGPASSWORD=$POSTGRES_PASSWORD;

if [ ! -d $DATA_PATH ]; then
    echo Data path ${DATA_PATH} does not exist
    exit 1
fi

raster_file=
force=
while [ $# -gt 0 ]; do
    case $1 in
        -h|--help)
            echo "Usage: $0 [-f] raster_file"
            echo "Only missing regions will be processed, unless the option -f is present"
            exit 0
            ;;
        -f|--force)
            force=1
            ;;
        *)
            if [ ! -z "$raster_file" ]; then
                echo Multiple file arguments specified
                exit 1
            fi
            raster_file=$1
            ;;
    esac
    shift
done

if [ -z "$raster_file" -o ! -f "$raster_file" ]; then
    echo Friction raster file $raster_file does not exist
    exit 1
fi

echo "Clipping friction raster to country-level regions (admin_level = 0)"
echo "Using raster file ${raster_file}"

mkdir -p $OUTPUT_PATH

regions="$(psql -d $POSTGRES_DB -U $POSTGRES_USER -h $POSTGRES_HOST -p $POSTGRES_PORT -t -A -c 'SELECT id FROM regions WHERE admin_level = 0;')"

for region in $regions; do
    echo -n Clipping for region $region ...
    output_file=$OUTPUT_PATH/$region.tif
    if [ ! -f "$output_file" ] || [ "$force" = "1" ]; then
        rm -f $output_file
        echo
        # TODO: we may want to cut by the envelope (even buffer it a little) instead
        # of the region itself to avoid errors and abrupt cuts in the region border
        gdalwarp -co COMPRESS=DEFLATE \
                 -dstnodata -3.4e+38 \
                 -crop_to_cutline -csql "SELECT the_geom FROM regions WHERE id = ${region}" \
                 -cutline PG:"dbname=${POSTGRES_DB} host=${POSTGRES_HOST} port=${POSTGRES_PORT} user=${POSTGRES_USER} password=${POSTGRES_PASSWORD}" \
                 $raster_file $output_file
    else
        echo Clipped friction exists for region
    fi
done