s3etag.sh
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| #!/bin/bash | |
| # Generate an S3 ETAG for a multipart upload file. | |
| # | |
| # From: https://gist.github.com/emersonf/7413337 | |
| # Author: Emerson Farrugia <https://github.com/emersonf> | |
| # Modified by: Richard Willis <https://github.com/badsyntax> | |
| # Modifications: Work with bytes instead of MB. | |
| # | |
| # MacOS only! | |
| if [ $# -ne 2 ]; then | |
| echo "Usage: $0 file partSizeInBytes" | |
| exit 0 | |
| fi | |
| file=$1 | |
| if [ ! -f "$file" ]; then | |
| echo "Error: $file not found." | |
| exit 1 | |
| fi | |
| partSizeInBytes=$2 | |
| fileSizeInBytes=$(stat -f%z "$file") | |
| parts=$((fileSizeInBytes / partSizeInBytes)) | |
| if [[ $((fileSizeInBytes % partSizeInBytes)) -gt 0 ]]; then | |
| parts=$((parts + 1)) | |
| fi | |
| checksumFile=$(mktemp -t s3md5) | |
| for ((part = 0; part < $parts; part++)); do | |
| skip=$((partSizeInBytes * part)) | |
| $(dd bs=1 count=$partSizeInBytes skip=$skip if="$file" 2>/dev/null | md5 >>$checksumFile) | |
| done | |
| echo $(xxd -r -p $checksumFile | md5)-$parts | |
| rm $checksumFile |
