Why does this curl command return Unexpected EOF

I am somewhat new to Bash and cURL and cannot understand out why this Bash file does not run without throwing an Unexpected EOF error.

This cURL command should upload a large file (in the example script below, somewhere between 300 and 400 MB) in 20 MB chunks to a storage service. Once all MB are uploaded, a second command "completes" the upload. Both commands use the same GUID.

Inside upload-bits.sh:

#!/bin/sh
for i in {0..20}; do
curl -X POST \
  https://community.<company>.com/api.ashx/v2/cfs/temporary.json \
  -H 'Rest-User-Token: 12345' \
  -F UploadContextId=21f23109-aac2-44ef-8b89-c0f62e67da4d \
  -F FileName='file.zip' \
  -F TotalChunks=20 \
  -F CurrentChunk=$i \
  -F '[email protected]'
done

The Bash script throws the Unexpected EOF error. I have tried the cURL command alone without the Bash portion of the script and replaced CurrentChunk with 0 and 1 without success. I also used a script validator, which confirmed there were no problems in the script. I also ran dos2unix on it in a desire to eliminate end-of-line issues.

I have not been able to use this second script yet, as the first script has not worked, but I am posting it for context if I am not explaining the desired overall process well.

complete-upload.sh:

curl -X POST \
  https://community.<company>.com/api.ashx/v2/media/371/files.json \
  -H 'Rest-User-Token: 12345' \
  -F 'Name=file.zip' \
  -F ContentType=application/zip \
  -F FileName='file.zip' \
  -F FileUploadContext=21f23109-aac2-44ef-8b89-c0f62e67da4d

I would be grateful for any tips or insights. Thank you.

Solution

Judging by the parameters passed to curl, the server expects chunked data.

However the curl command sends the whole file 20 times.

Looking at definition of CurrentChunk at https://community.telligent.com/community/10/w/api-documentation/61481/upload-cfs-rest-endpoint , perhaps a modification like this would work:

#!/bin/bash

# using GNU split options will make arithmetic simpler
# with -d, we may get numbers like 09 which are invalid octal
# start from 101 if CurrentChunk is one-based
# start from 100 if CurrentChunk is zero-based
split -b20M -a3 --numeric-suffixes=101 file.zip part.

partlist=( part.* )
numparts=${#partlist[@]}

for part in ${partlist[@]}; do
  i=$(( ${part##*.}-100 ))
  curl -X POST \
    https://community.<company>.com/api.ashx/v2/cfs/temporary.json \
    -H 'Rest-User-Token: 12345' \
    -F UploadContextId=21f23109-aac2-44ef-8b89-c0f62e67da4d \
    -F FileName='file.zip' \
    -F TotalChunks=$numparts \
    -F CurrentChunk=$i \
    -F 'file=@'$part
done

rm ${partlist[@]}