#!/bin/bash
# Copyright 2012 Cloudera Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Check if a reference githash exists in hdfs; If it does, diff the directories that
# contain the schemas against the current HEAD.
# This script exits with 0 and 1 as the returncodes
#  - 0 implies that the schema diff is emppty, or that a reference githash was not found.
#  - 1 implies that the schemas have changed.
set -ex
# If /test-warehouse/githash.txt does not exist, exit with a 0
hdfs dfs -test -e  /test-warehouse/githash.txt || { exit 0; }
GIT_HASH=$(echo $(hdfs dfs -cat /test-warehouse/githash.txt))
# Check whether a non-empty diff exists.
# TODO: Make this more granular (on the level of a dataset)
git diff --exit-code ${GIT_HASH}..HEAD ${IMPALA_HOME}/testdata/datasets