A `docker-compose` wrapper for multiple configuration files with relative paths

docker-compose.sh

#!/usr/bin/env bash                                                 
                                                                 
TMP_FILE=/tmp/docker-compose.$$.yaml                                   
                                                                    
finish() {                                                          
  rm ${TMP_FILE} ${TMP_FILE}.tmp 2>/dev/null                        
}                                                                   
                                                                    
trap finish EXIT                                                    
                                                                    
compose-config() {                                                  
  mv -f ${TMP_FILE} ${TMP_FILE}.tmp                                 
  docker-compose -f ${1} -f ${TMP_FILE}.tmp config > ${TMP_FILE}    
                                                                    
  rm -f ${TMP_FILE}.tmp 2>/dev/null                                 
}                                                                                                                                        
                                                                    
args=()                                                              
files=()                                                             
                                                                     
while :; do                                                          
  getopts ":" opt                                                    
  case $OPTARG in                                                    
    f) files+=(${!OPTIND})                                           
    ;;                                                               
    ?) args+=("-${OPTARG}" "${!OPTIND}")                             
    ;;                                                               
    *) args+=("${!OPTIND}")                                          
    ;;                                                               
  esac                                                               
                                                                     
  ((OPTIND++))                                                       
  [ $OPTIND -gt $# ] && break                                        
done                                                                 
                                                                     
echo 'version: "3"' > ${TMP_FILE}                                    
                                                                     
for f in ${files[@]}; do                                             
  compose-config ${f}                                                
done                                                                 
                                                                     
docker-compose -f ${TMP_FILE} ${args[@]}                             
exit $?