#! /bin/sh

set -e
set -o pipefail

if [ "${S3_ACCESS_KEY_ID}" = "**None**" ]; then
  echo "You need to set the S3_ACCESS_KEY_ID environment variable."
  exit 1
fi

if [ "${S3_SECRET_ACCESS_KEY}" = "**None**" ]; then
  echo "You need to set the S3_SECRET_ACCESS_KEY environment variable."
  exit 1
fi

if [ "${S3_BUCKET}" = "**None**" ]; then
  echo "You need to set the S3_BUCKET environment variable."
  exit 1
fi

if [ "${POSTGRES_DATABASE}" = "**None**" ]; then
  echo "You need to set the POSTGRES_DATABASE environment variable."
  exit 1
fi

if [ "${POSTGRES_HOST}" = "**None**" ]; then
  if [ -n "${POSTGRES_PORT_5432_TCP_ADDR}" ]; then
    POSTGRES_HOST=$POSTGRES_PORT_5432_TCP_ADDR
    POSTGRES_PORT=$POSTGRES_PORT_5432_TCP_PORT
  else
    echo "You need to set the POSTGRES_HOST environment variable."
    exit 1
  fi
fi

if [ "${POSTGRES_USER}" = "**None**" ]; then
  echo "You need to set the POSTGRES_USER environment variable."
  exit 1
fi

if [ "${POSTGRES_PASSWORD}" = "**None**" ]; then
  echo "You need to set the POSTGRES_PASSWORD environment variable or link to a container named POSTGRES."
  exit 1
fi

if [ "${S3_ENDPOINT}" == "**None**" ]; then
  AWS_ARGS=""
else
  AWS_ARGS="--endpoint-url ${S3_ENDPOINT}"
fi

# env vars needed for aws tools
export AWS_ACCESS_KEY_ID=$S3_ACCESS_KEY_ID
export AWS_SECRET_ACCESS_KEY=$S3_SECRET_ACCESS_KEY
export AWS_DEFAULT_REGION=$S3_REGION

export PGPASSWORD=$POSTGRES_PASSWORD
POSTGRES_HOST_OPTS="-h $POSTGRES_HOST -p $POSTGRES_PORT -U $POSTGRES_USER $POSTGRES_EXTRA_OPTS"

echo "Creating dump of ${POSTGRES_DATABASE} database from ${POSTGRES_HOST}..."

pg_dump $POSTGRES_HOST_OPTS $POSTGRES_DATABASE | gzip > dump.sql.gz

echo "Uploading dump to $S3_BUCKET"

cat dump.sql.gz | aws $AWS_ARGS s3 cp - s3://$S3_BUCKET/$S3_PREFIX/${POSTGRES_DATABASE}_$(date +"%Y-%m-%dT%H:%M:%SZ").sql.gz || exit 2

if [ "${DELETE_OLDER_THAN}" != "**None**" ]; then
  aws $AWS_ARGS s3 ls s3://$S3_BUCKET/$S3_PREFIX/ | grep " PRE " -v | while read -r line;
    do
      created=`echo $line|awk {'print $1" "$2'}`
      created=`date -d "$created" +%s`
      older_than=`date -d "$DELETE_OLDER_THAN" +%s`
      if [ $created -lt $older_than ]
        then
          fileName=`echo $line|awk {'print $4'}`
          if [ $fileName != "" ]
            then
              printf 'Deleting "%s"\n' $fileName
              aws $AWS_ARGS s3 rm s3://$S3_BUCKET/$S3_PREFIX/$fileName
          fi
      fi
    done;
fi

echo "SQL backup uploaded successfully"