Curl JSON encoded in UTF-8

Important note: I'm using Cygwin

I retrieve JSON from a file that I alter before sending it to a server using curl. By now everything is ok except one thing, when the server receive the JSON, every special characters (with accents, etc) aren't well encoded. I suppose this was due to the fact that my JSON wasn't encoded in UTF-8 before being sent but I don't manage to convert it.

Here is the code:

sed -i 's/\r//g' $file
fileContent=`cat $file`

result=$(jq -c -j ".docs[$docIndex] + { \"_rev\": \"$rev\" }"<<<"$fileContent")            result="{\"docs\":[$result]}"

result=$result | sed 's/\r//g'
result=$result | iconv -t "UTF-8"
s=$(curl -H "Content-Type: application/json; charset=UTF-8" -H "Cache-Control: no-cache" -d "$result" $2/$3/_bulk_docs --silent)

My bash script and my JSON files are both encoded in UTF-8. My LANG variable seems to be UTF-8. I checked with this: [[ $LANG =~ UTF-8$ ]] && echo "Uses UTF-8 encoding.."

Any idea?

Update

Here is the full script:

#!/bin/bash

# $1 = directory containing JSON files
# $2 = server url (+ port)
# $3 = database name

#Loop on every file of the given directory
for file in "$1"/*; do

    #Try to insert every document of a specific JSON file and retrieve their status (200 = OK; 409 = conflict)
    allStatus=$(curl -H "Content-Type: application/json" -H "Cache-Control: no-cache" --data-binary "@$file" $2/$3/_bulk_docs --silent | jq '.[] |.status' | tr -d '\r')
    docIndex=0

    #Loop on every status (one status = one document)
    while IFS=' ' read -ra statusArray; do
      for status in "${statusArray[@]}"; do

        #Remove unwanted windows characters of the file
        sed -i 's/\r//g' $file
        fileContent=`cat $file`

        #Retrieve the id of the current document
        id=`jq -r -j ".docs[$docIndex]._id"<<<"$fileContent" | tr -d '\r'`

        if [ "$status" = "409" ]
        then 
            #Retrieve the revision of the current document and add it to the document 
            rev=$(curl -X GET --header 'Accept: application/json' $2/$3/$id?revs=true --silent | jq -r -j '._rev' | tr -d '\r')
            result=$(jq -c -j ".docs[$docIndex] + { \"_rev\": \"$rev\" }"<<<"$fileContent")

            #Wrap the document inside {"docs":[]}
            result="{\"docs\":[$result]}"

            #Remove unwanted windows characters before sending the document (again)
            result=$result | sed 's/\r//g'
            result=$result | iconv -t "UTF-8"
            s=$(curl -H "Content-Type: application/json; charset=UTF-8" -H "Cache-Control: no-cache" -d "$result" $2/$3/_bulk_docs --silent)

            #Echo result
            echo $s
        else
          #Status should be 200.
          echo 'status: '$status ' - ' $id
        fi

        docIndex=$((docIndex+1))

      done
    done <<< "$allStatus"
done

This script aims to upsert documents inside a NoSQL database. If first try to insert and if if fails it retrieves a property (the revision) of the document, append to it and then retry once.

I know this script could be improved but this is my first bash script and it won't be used in production (only for testing, etc.).