shell编写

#判断环境变量BLACK_LIST的字符串长度是否为0#设置shell变量BLACK_LIST的值为环境变量BLACK_LIST的值if [ -n "$BLACK_LIST" ]; then     BLACK_LIST="--blacklist $BLACK_LIST"fi#判断环境变量PRODUCER_COUNT的字符串长度是否不为0#设置shell变量PRODUCER_COUNT的值为环境变量DEFAULT_PRODUCERS的值if [ -z "$PRODUCER_COUNT" ]; then    PRODUCER_COUNT=$DEFAULT_PRODUCERSfiif [ -n "$SOURCE" ];then    #截取环境变量SOURCE_DEST从第一个字符开始的连续四个字符    #SOURCE_BROKERS=`expr substr "$SOURCE_DEST" 1 4`    #将环境变量SOURCE的值有小写字母转化成大写字母    SOURCE=`echo $SOURCE | tr a-z A-Z`    #将以shell变量的值为名字的变量的值赋给shell变量SOURCE_BROKERS    SOURCE_BROKERS=`eval echo "$"$SOURCE`    echo "source $SOURCE_BROKERS"else    echo "Specify SOURCE"    exit 1if [ -n "$DEST" ];then#字符串连接        CONSUMER_GROUP_ID=${DEST}"_mirror_"${MARATHON_APP_ID}    echo "consumer_group_id $CONSUMER_GROUP_ID"    #DEST_BROKERS=`expr substr "$SOURCE_DEST" 6 4`    DEST=`echo $DEST | tr a-z A-Z`    DEST_BROKERS=`eval echo "$"$DEST`    echo "dest $DEST_BROKERS"else    echo "Specify DEST"    exit 2fi#按照如下内容生成../config/consumer.config的配置文件cat <<- EOF > ../config/consumer.config    bootstrap.servers=$SOURCE_BROKERS    group.id=$CONSUMER_GROUP_IDEOFcat <<- EOF > ../config/producer.config    bootstrap.servers=$DEST_BROKERS    compression.codes=none    producer.type=async    serializer.class=kafka.serializer.DefaultEncoderEOF

参考链接
linux shell 的here document 用法 (cat << EOF)