pre receive hook for gitlab to limit file size on upload via the web interface and web IDE

check-size-hook.bash

#!/bin/bash

# pre-receive server hook to check file size of files submitted by webinterface in gitlab
# 
# sources:
# https://gist.github.com/nauar/826f85d25d692d9bc009312cb71577dd


LOG_FILE="/var/log/datahub/size-check-hook.log"
GITCMD="git"
NULLSHA="0000000000000000000000000000000000000000"
EMPTYTREESHA=$($GITCMD hash-object -t tree /dev/null)
MAXSIZE="1" # set your maximum file size in MB here
MAXBYTES=$(( $MAXSIZE * 1048576 ))

function log() {
    moment=`date '+%d/%m/%Y %H:%M:%S'`
    echo -e "[ $moment ] [ SIZE CHECK ] $1" >> $LOG_FILE
}

# do checks only if files are added via web interface, upload single file and WEB IDE
if [ "$GL_PROTOCOL" = "web" ]; then
        log "Starting validation: $GL_ID\t$GL_PROJECT_PATH\t$GL_PROTOCOL\t$GL_REPOSITORY\t$GL_USERNAME"
        while read oldref newref refname; do

            log "OLDREF: $oldref NEWREF: $newref REFNAME: $refname"

            # Avoid removed branches
            if [ "${newref}" = "${NULLSHA}" ]; then
                continue
            fi

            # Set oldref properly if this is branch creation.
            if [ "${oldref}" = "${NULLSHA}" ]; then
                oldref=$EMPTYTREESHA
            fi

            # Ignore case
            shopt -s nocaseglob

            newFiles=$($GITCMD diff --stat --name-only --diff-filter=ACMRT ${oldref}..${newref})

            if [[ $? -ne 0 ]]; then
                log "Error 101: Repository incosistency. Cancelling push..."
                echo "GL-HOOK-ERR: Repository incosistency. Cancelling push...";
                exit 1;
            fi

            old_IFS=$IFS
            IFS='
            '
            for filename in $newFiles; do
                # get file size info
                log "Filename: $filename"
               filesize=$($GITCMD cat-file -s "${newref}:${filename}") 2>> $LOG_FILE

                if [[ -z $filesize  ]]; then filesize=0; fi
                filesize_mb=$(($filesize / 1048576))

                # check file size, exit if too big
                if [ "${filesize}" -gt "${MAXBYTES}" ]; then
                    log "File $filename is greater than $MAXSIZE MB. Its size is $filesize_mb MB."
                    echo "GL-HOOK-ERR: At least one of your submitted files ($filename) has been to big ($filesize_mb MB). Max filesize is $MAXSIZE MB. Please use git-lsf to submit bigger files to your ARC.";
                    exit 1
                fi

            done
            IFS=$old_IFS
        done
fi