Add support for providing extra args for the AWS CLI

README.md

@@ -181,6 +181,7 @@ Variable | Default | Notes
 `AWS_ACCESS_KEY_ID` |  | Required when using `AWS_S3_BUCKET_NAME`.
 `AWS_SECRET_ACCESS_KEY` |  | Required when using `AWS_S3_BUCKET_NAME`.
 `AWS_DEFAULT_REGION` |  | Optional when using `AWS_S3_BUCKET_NAME`. Allows you to override the AWS CLI default region. Usually not needed.
+`AWS_EXTRA_ARGS` |  | Optional additional args for the AWS CLI. Useful for e.g. providing `--endpoint-url <url>` for S3-interopable systems, such as DigitalOcean Storage.
 `INFLUXDB_URL` |  | When provided, backup metrics will be sent to an InfluxDB instance at this URL, e.g. `https://influxdb.example.com`.
 `INFLUXDB_DB` |  | Required when using `INFLUXDB_URL`; e.g. `my_database`.
 `INFLUXDB_CREDENTIALS` |  | Required when using `INFLUXDB_URL`; e.g. `user:pass`.

src/backup.sh

@@ -80,7 +80,7 @@ if [ ! -z "$AWS_S3_BUCKET_NAME" ]; then
   info "Uploading backup to S3"
   echo "Will upload to bucket \"$AWS_S3_BUCKET_NAME\""
   TIME_UPLOAD="$(date +%s.%N)"
-  aws s3 cp --only-show-errors "$BACKUP_FILENAME" "s3://$AWS_S3_BUCKET_NAME/"
+  aws $AWS_EXTRA_ARGS s3 cp --only-show-errors "$BACKUP_FILENAME" "s3://$AWS_S3_BUCKET_NAME/"
   echo "Upload finished"
   TIME_UPLOADED="$(date +%s.%N)"
 fi

src/entrypoint.sh

@@ -8,6 +8,7 @@ cat <<EOF > env.sh
 BACKUP_SOURCES="${BACKUP_SOURCES:-/backup}"
 BACKUP_CRON_EXPRESSION="${BACKUP_CRON_EXPRESSION:-@daily}"
 AWS_S3_BUCKET_NAME="${AWS_S3_BUCKET_NAME:-}"
+AWS_EXTRA_ARGS="${AWS_EXTRA_ARGS:-}"
 BACKUP_FILENAME=${BACKUP_FILENAME:-"backup-%Y-%m-%dT%H-%M-%S.tar.gz"}
 BACKUP_ARCHIVE="${BACKUP_ARCHIVE:-/archive}"
 BACKUP_WAIT_SECONDS="${BACKUP_WAIT_SECONDS:-0}"