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@DecisionNerd
Created November 13, 2015 03:13
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CSV to JSON converter using BASH. Original script from http://blog.secaserver.com/2013/12/convert-csv-json-bash/
#!/bin/bash
# CSV to JSON converter using BASH
# original script from http://blog.secaserver.com/2013/12/convert-csv-json-bash/
# thanks SecaGuy!
# Usage ./csv2json.sh input.csv > output.json
input=$1
[ -z $1 ] && echo "No CSV input file specified" && exit 1
[ ! -e $input ] && echo "Unable to locate $1" && exit 1
read first_line < $input
a=0
headings=`echo $first_line | awk -F, {'print NF'}`
lines=`cat $input | wc -l`
while [ $a -lt $headings ]
do
head_array[$a]=$(echo $first_line | awk -v x=$(($a + 1)) -F"," '{print $x}')
a=$(($a+1))
done
c=0
echo "{"
while [ $c -lt $lines ]
do
read each_line
if [ $c -ne 0 ]; then
d=0
echo -n "{"
while [ $d -lt $headings ]
do
each_element=$(echo $each_line | awk -v y=$(($d + 1)) -F"," '{print $y}')
if [ $d -ne $(($headings-1)) ]; then
echo -n ${head_array[$d]}":"$each_element","
else
echo -n ${head_array[$d]}":"$each_element
fi
d=$(($d+1))
done
if [ $c -eq $(($lines-1)) ]; then
echo "}"
else
echo "},"
fi
fi
c=$(($c+1))
done < $input
echo "}"
@briangranatir
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briangranatir commented May 23, 2017

Great script!

If you want to wrap all tag names in quotes, and all values that start with an alphabetic char with quotes, you can go with this:

input=$1
 
[ -z $1 ] && echo "No CSV input file specified" && exit 1
[ ! -e $input ] && echo "Unable to locate $1" && exit 1
 
read first_line < $input
a=0
headings=`echo $first_line | awk -F, {'print NF'}`
lines=`cat $input | wc -l`
while [ $a -lt $headings ]
do
  head_array[$a]=$(echo $first_line | awk -v x=$(($a + 1)) -F"," '{print $x}')
  a=$(($a+1))
done
 
c=0
echo "{"
while [ $c -lt $lines ]
do
  read each_line
  if [ $c -ne 0 ]; then
    d=0
    echo -n "{"
    while [ $d -lt $headings ]
    do
      each_element=$(echo $each_line | awk -v y=$(($d + 1)) -F"," '{print $y}')
      if [[ $each_element == [a-zA-Z]* ]]; then
        each_element="\"${each_element}\""                     
      fi
      if [ $d -ne $(($headings-1)) ]; then
        echo -n "\"${head_array[$d]}\":$each_element,"
      else
        echo -n "\"${head_array[$d]}\":$each_element"
      fi
      d=$(($d+1))
    done
    if [ $c -eq $(($lines-1)) ]; then
      echo "}"
    else
      echo "},"
    fi
  fi
c=$(($c+1))
done < $input
echo "}"

@albfan
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albfan commented Jul 3, 2017

To generate a correct json:

  • Start with an array []
  • empty values = null
  • values with a letter are strings
  • config separator with SEP variable
#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json

#set -x

input=$1

SEP=";"

[ -z $1 ] && echo "No CSV input file specified" && exit 1
[ ! -e $input ] && echo "Unable to locate $1" && exit 1

read first_line < $input
a=0
headings=`echo $first_line | awk -F"$SEP" {'print NF'}`
lines=`cat $input | wc -l`
while [ $a -lt $headings ]
do
        head_array[$a]=$(echo $first_line | awk -v x=$(($a + 1)) -F"$SEP" '{print $x}')
        a=$(($a+1))
done

c=0
echo "["
while [ $c -lt $lines ]
do
        read each_line
        if [ $c -ne 0 ]; then
                d=0
                echo -n "{"
                while [ $d -lt $headings ]
                do
                        each_element=$(echo $each_line | awk -v y=$(($d + 1)) -F"$SEP" '{print $y}')
                        if [[ $each_element == *[a-zA-Z]* ]]; then
                          each_element="\"${each_element}\""
                        fi
                        if [[ $each_element == "" ]]; then
                          each_element="null"
                        fi
                        if [ $d -ne $(($headings-1)) ]; then
                          echo -n "\"${head_array[$d]}\":$each_element,"
                        else
                          echo -n "\"${head_array[$d]}\":$each_element"
                        fi
                        d=$(($d+1))
                done
                if [ $c -eq $(($lines-1)) ]; then
                        echo "}"
                else
                        echo "},"
                fi
        fi
        c=$(($c+1))
done < $input
echo "]"

@tarikozket
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Upgraded albfan's version. Added parenthesis to regex so if you have any stuff going on with parenthesis in your data like financials or phone numbers, it captures them too and generates a valid JSON. Also, I have defined a variable for the regex and moved it to the top for convenience.

#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json

#set -x

input=$1

SEP=";"
CAPTURE=*[a-zA-Z\(\)]*

[ -z $1 ] && echo "No CSV input file specified" && exit 1
[ ! -e $input ] && echo "Unable to locate $1" && exit 1

read first_line < $input
a=0
headings=`echo $first_line | awk -F"$SEP" {'print NF'}`
lines=`cat $input | wc -l`
while [ $a -lt $headings ]
do
        head_array[$a]=$(echo $first_line | awk -v x=$(($a + 1)) -F"$SEP" '{print $x}')
        a=$(($a+1))
done

c=0
echo "["
while [ $c -lt $lines ]
do
        read each_line
        if [ $c -ne 0 ]; then
                d=0
                echo -n "{"
                while [ $d -lt $headings ]
                do
                        each_element=$(echo $each_line | awk -v y=$(($d + 1)) -F"$SEP" '{print $y}')
                        if [[ $each_element == $CAPTURE ]]; then
                          each_element="\"${each_element}\""
                        fi
                        if [[ $each_element == "" ]]; then
                          each_element="null"
                        fi
                        if [ $d -ne $(($headings-1)) ]; then
                          echo -n "\"${head_array[$d]}\":$each_element,"
                        else
                          echo -n "\"${head_array[$d]}\":$each_element"
                        fi
                        d=$(($d+1))
                done
                if [ $c -eq $(($lines-1)) ]; then
                        echo "}"
                else
                        echo "},"
                fi
        fi
        c=$(($c+1))
done < $input
echo "]"

@jwkblades
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jwkblades commented Oct 21, 2017

Updated @tarikozket's version to help it out with some more standard (at least in my use-case) CSVs. Added a slightly more pretty output structure and refactored to streamline things a little. I also went through and fixed an annoyance where a \r (carriage return) would cause lines to get overwritten or otherwise mangled.

NOTE - This has a bug, and I believe that it exists in every version of the script provided in this gist, but an entry that contains a comma will be truncated strangely. As a result, I would suggest not using any commas in your file except for delimiting fields.

This update also requires extended globs as it uses them to determine if it should quote a field when outputting it.

#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json

#set -x
shopt -s extglob

input="${1:-}"
SEP=","

[ -z "${input}" ] && echo "No CSV input file specified" && exit 1
[ ! -e "${input}" ] && echo "Unable to locate ${input}" && exit 1

read first_line < "${input}"
a=0
headings=`echo ${first_line} | awk -F"${SEP}" {'print NF'}`
lines=`cat "${input}" | wc -l`
while [ ${a} -lt ${headings} ]
do
    head_array[${a}]=$(echo ${first_line} | awk -v x=$(( ${a} + 1 )) -F"${SEP}" '{print $x}' | sed 's/\r//g')
    a=$(( ${a} + 1 ))
done

c=0
echo "["
while [ ${c} -lt ${lines} ]
do
    read each_line
    each_line="$(echo "${each_line}" | sed 's/\r//g')"

    if [[ ${c} -eq 0 ]]; then
        c=$(( ${c} + 1 ))
    else
        d=0
        echo "    {"
        while [[ ${d} -lt ${headings} ]]; do
            item="$(echo "${each_line}" | awk -v x=$(( ${d} + 1 )) -F"${SEP}" '{print $x}')"
            echo -n "        \"${head_array[${d}]}\": "
            case "${item}" in
                "")
                    echo -n "null"
                    ;;
                null|true|false|\"*\"|+([0123456789]))
                    echo -n ${item}
                    ;;
                *)
                    echo -n "\"${item}\""
                    ;;
            esac
            d=$(( ${d} + 1 ))
            [[ ${d} -lt ${headings} ]] && echo "," || echo ""
        done

        echo -n "    }"

        c=$(( ${c} + 1 ))
        [[ ${c} -lt ${lines} ]] && echo "," || echo ""
    fi

done < "${input}"
echo "]"

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ghost commented Oct 23, 2017

@jwkblades beautiful piece there

@jwkblades
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Okay, I didn't like that we couldn't use commas, so I updated it to work with them. This could probably be done in a more elegant way by someone who is better with awk or sed than I am, but here is a quick implementation that works for at least all the CSVs I have thrown at it (an admittedly small set).

#!/bin/bash
  
# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json

#set -x
shopt -s extglob

input="${1:-}"
SEP=","

[ -z "${input}" ] && echo "No CSV input file specified" && exit 1
[ ! -e "${input}" ] && echo "Unable to locate ${input}" && exit 1

csv_nextField()
{
    local line="$(echo "${1}" | sed 's/\r//g')"
    local start=0
    local stop=0

    if [[ -z "${line}" ]]; then
        return 0
    fi

    local offset=0
    local inQuotes=0
    while [[ -n "${line}" ]]; do
        local char="${line:0:1}"
        line="${line:1}"

        if [[ "${char}" == "${SEP}" && ${inQuotes} -eq 0 ]]; then
            inQuotes=0
            break
        elif [[ "${char}" == '"' ]]; then
            if [[ ${inQuotes} -eq 1 ]]; then
                inQuotes=0
            else
                inQuotes=1
            fi
        else
            echo -n "${char}"
        fi
        offset=$(( ${offset} + 1 ))
    done

    echo ""
    return $(( ${offset} + 1 ))
}

read first_line < "${input}"
a=0
headings=`echo ${first_line} | awk -F"${SEP}" {'print NF'}`
lines=`cat "${input}" | wc -l`

while [[ ${a} -lt ${headings} ]]; do
    field="$(csv_nextField "${first_line}")"
    first_line="${first_line:${?}}"
    head_array[${a}]="${field}"
    a=$(( ${a} + 1 ))
done

c=0
echo "["
while [ ${c} -lt ${lines} ]
do
    read each_line
    each_line="$(echo "${each_line}" | sed 's/\r//g')"

    if [[ ${c} -eq 0 ]]; then
        c=$(( ${c} + 1 ))
    else
        d=0
        echo "    {"
        while [[ ${d} -lt ${headings} ]]; do
            item="$(csv_nextField "${each_line}")"
            each_line="${each_line:${?}}"
            echo -n "        \"${head_array[${d}]}\": "
            case "${item}" in
                "")
                    echo -n "null"
                    ;;
                null|true|false|\"*\"|+([0123456789]))
                    echo -n ${item}
                    ;;
                *)
                    echo -n "\"${item}\""
                    ;;
            esac
            d=$(( ${d} + 1 ))
            [[ ${d} -lt ${headings} ]] && echo "," || echo ""
        done

        echo -n "    }"

        c=$(( ${c} + 1 ))
        [[ ${c} -lt ${lines} ]] && echo "," || echo ""
    fi

done < "${input}"
echo "]"

@mcmellow
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mcmellow commented Jan 6, 2018

My csv file is tab seperated, what do I use for SEP= ?

Greetings
McMelloW

@outwitevil
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outwitevil commented Feb 6, 2018

This is fantastic!
Using @jwkblades latest version.
Just wanted to add that by changing
input="${1:-}"
to:
input="${1:-/dev/stdin}"
It will let you take stdin as an input, instead of specifying a file. Which fits my use case perfectly.
Thank you all.

-- edit That only seems to work then the piped data exists in a file already.
cat test.csv | csv2json.sh
but not
horribly_old_custom_sql_query_tool "select * from table_name limit 10" | csv2json > output.json
Working to see if I can't simplify a tool and have it skip writing to the csv in the first place.

@outwitevil
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outwitevil commented Feb 28, 2018

ok. This version lets me use either piped stdin or read from a file:

#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json
#       cat <input.csv> | csv2json > output.json
#set -x
shopt -s extglob

input="${1:-/dev/stdin}"

SEP=","

[ -z "${input}" ] && echo "No CSV input file specified" && exit 1
[ ! -e "${input}" ] && echo "Unable to locate ${input}" && exit 1

csv_nextField()
{
    local line="$(echo "${1}" | sed 's/\r//g')"
    local start=0
    local stop=0

    if [[ -z "${line}" ]]; then
        return 0
    fi

    local offset=0
    local inQuotes=0
    while [[ -n "${line}" ]]; do
        local char="${line:0:1}"
        line="${line:1}"

        if [[ "${char}" == "${SEP}" && ${inQuotes} -eq 0 ]]; then
            inQuotes=0
            break
        elif [[ "${char}" == '"' ]]; then
            if [[ ${inQuotes} -eq 1 ]]; then
                inQuotes=0
            else
                inQuotes=1
            fi
        else
            echo -n "${char}"
        fi
        offset=$(( ${offset} + 1 ))
    done

    echo ""
    return $(( ${offset} + 1 ))
}

read -r first_line < "${input}"
a=0
headings=$(echo "${first_line}" | awk -F"${SEP}" {'print NF'})

if [ "${input}" = "/dev/stdin" ]; then
  while read -r line
  do
    lines_str+="$line"$'\n'
    c=1
  done < "${input}"
else
  lines_str="$(cat "${input}")"
  c=0
fi

lines_num=$(echo "${lines_str}" | wc -l)

while [[ ${a} -lt ${headings} ]]; do
    field="$(csv_nextField "${first_line}")"
    first_line="${first_line:${?}}"
    head_array[${a}]="${field}"
    a=$(( ${a} + 1 ))
done

#c=0
echo "["
while [ ${c} -lt ${lines_num} ]
do
    read -r each_line
    each_line="$(echo "${each_line}" | sed 's/\r//g')"

    if [[ ${c} -eq 0 ]]; then
        c=$(( ${c} + 1 ))
    else
        d=0
        echo "    {"
        while [[ ${d} -lt ${headings} ]]; do
            item="$(csv_nextField "${each_line}")"
            each_line="${each_line:${?}}"
            echo -n "        \"${head_array[${d}]}\": "
            case "${item}" in
                "")
                    echo -n "null"
                    ;;
                null|true|false|\"*\"|+([0123456789]))
                    echo -n ${item}
                    ;;
                *)
                    echo -n "\"${item}\""
                    ;;
            esac
            d=$(( ${d} + 1 ))
            [[ ${d} -lt ${headings} ]] && echo "," || echo ""
        done

        echo -n "    }"

        c=$(( ${c} + 1 ))
        [[ ${c} -lt ${lines_num} ]] && echo "," || echo ""
    fi

done <<< "${lines_str}"
echo "]"

@linosteenkamp
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linosteenkamp commented Mar 9, 2018

Had some issues with this on MacOS as every echo inserted a line break, also had ^M at the end of the last header and last item in every line. My input files also had some blank lines that caused issues, so had to find a solution for that.

Using @jwkblades first version as the comma issue did not impact me, and if it would become an issue I will use a different delimiter.

refactored the code with the following changes:

  • removed all blank lines in the input file
  • replaced all echo's with printf
  • removed ^M form the last field
  • simplified the code some more

Now works well against my files on both MacOS and Ubuntu

EDIT
Will work with piped stdin i.e. sqlite3 output or read from a file as per @outwitevil
Add the ability to quote unquoted ip adressess.

#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json

shopt -s extglob

input="${1:-/dev/stdin}"
SEP=","

[ -z "${input}" ] && printf "No CSV input file specified" && exit 1
[ ! -e "${input}" ] && printf "Unable to locate ${input}" && exit 1

data=$(sed '/^$/d' "${input}")
line_count=$(printf "${data}" | wc -l)

printf "[\n"
row=0
while IFS=$'\n\r' read -r line; do
    if [[ ${row} -eq 0 ]]; then
        IFS="$SEP" read -ra head_items <<< "${line}"
    else
        IFS="$SEP" read -ra line_items <<< "${line}"
        printf "\t{\n"
        col=0
        for item in "${line_items[@]}"; do
            printf  "\t\t\"${head_items[${col}]}\": "
            case ${item} in
                \"\")
                    printf "null"
                    ;;
                \"*\")
                    printf "${item}"
                    ;;
                *.*.*.*)
                    printf "\"${item}\""
                    ;;
                null|true|false|+([0-9.]))
                    printf "${item}"
                    ;;
                *)
                    printf "\"${item}\""
                    ;;
            esac
            (( col++ ))
            [[ ${col} -lt ${#head_items[@]} ]] && printf ",\n" || printf "\n"
        done
        printf "\t}"
        [[ ${row} -lt ${line_count} ]] && printf ",\n" || printf "\n"
    fi
    (( row++ ))
done <<< "${data}"
printf "]"

@aleskar
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aleskar commented Jun 26, 2018

Many thanks to each of you! just what I was looking for!

@deajan
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deajan commented Jul 5, 2018

Here's a quick and dirty version that works on shells like Busybox ash that don't handle arrays

function CSV2JSON {
	local inputFile="${1}"				# Input csv text
	local separator="${2:-,}"		# Separator, defaults to ','
	
	local lineCounter=0
	local numberOfHeadings=0
	local headingsCounter=0
	local elementNumber=0
	
	# Since we do not have arrays in ash, we assign elements via eval "header$number"
	# variables header[0-9]* cannot be declared as local
	
	
	echo -e "\t["
	while IFS= read -r line; do
		if [ "$line" == "" ] || [ "${line:0:1}" == "#" ]; then
			continue
		fi
		
		if [ $lineCounter -eq 0 ]; then
			numberOfHeadings=$(echo $line | awk -F"$separator" {'print NF'})
			while [ $headingsCounter -lt $numberOfHeadings ]; do
				eval "header$headingsCounter=\"$(echo $line | awk -v x=$((headingsCounter+1)) -F"$separator" '{print $x}')\""
				headingsCounter=$((headingsCounter+1))
			done
		else
			echo -e "\t\t{"
			elementNumber=0
			while [ $elementNumber -lt $numberOfHeadings ]; do
				element="$(echo $line | awk -v y=$(($elementNumber+1)) -F"$separator" '{print $y}')"
				if [ "$element" == "" ]; then
					element="null"
				fi
				
				eval "echo -e \"\\t\\t\\\"\$header$elementNumber\\\" : \\\"$element\\\",\""
				
				elementNumber=$((elementNumber+1))
			done
			
			echo -e "\t\t},"
		fi
		lineCounter=$((lineCounter+1))
	done < "$inputFile"
	echo -e "\t],"
}

@deajan
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deajan commented Jul 5, 2018

Here's another version that works with Busybox, and does not rely on eval, altough using cut in order to find corresponding headers has a little performance impact.
Function should be highly portable

function CSV2JSON2 {
	local inputFile="${1}"				# Input csv text
	local separator="${2:-,}"			# Separator, defaults to ','
	
	local firstLine
	local lineCounter=0
	local numberOfHeadings=0
	local elementNumber=0
	local element
		
	while IFS= read -r line; do
		if [ "$line" == "" ] || [ "${line:0:1}" == "#" ]; then
			continue
		fi
		
		if [ $lineCounter -eq 0 ]; then
			numberOfHeadings=$(($(echo $line | grep -o "$separator" | wc -l)+1))
			firstLine="$line"
		else
			echo -e "\t\t{"
			elementNumber=1
			while [ $elementNumber -lt $numberOfHeadings ]; do
				headerElement="$(echo $firstLine | cut -d"$separator" -f$elementNumber)"
				element="$(echo $line | cut -d"$separator" -f$elementNumber)"

				if [ "$element" == "" ]; then
					element="null"
				fi
				
				echo -e "\t\t\"$headerElement\" : \"$element\","
				
				elementNumber=$((elementNumber+1))
			done
			
			echo -e "\t\t},"
		fi
		lineCounter=$((lineCounter+1))
	done < "$inputFile"
	# Add [ ] if more than one item in list
	if [ $lineCounter -gt 2 ]; then
		sed -i.tmp '1s/^/\t[\n/' "$outputFile"
		echo -e "\t]," >> "$outputFile"
	fi
}

Use with jsonOutput = "$(CSV2JSON2 "inputFile")"

@grmpfhmbl
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grmpfhmbl commented Sep 14, 2018

@linosteenkamp's version does not work with CSV that contain quoted comma (",") e.g. printf "head1,head2,head3\n1,\"foo, bar, baz\",\"foo bar baz\"" | ./csv2json.sh will result in

[
        {
                "head1": 1,
                "head2": ""foo",
                "head3": " bar"
                "": " baz""
                "": "foo bar baz"
        }
]

Quick fix for @outwitevil's script (https://gist.github.com/dsliberty/3de707bc656cf757a0cb#gistcomment-2103308) is to replace the \r in the sed regex with $(printf '\r'). The script will still struggle with empty lines, so you have to delete them beforehand. A simple one-liner

printf "head1,head2,head3\n\n\n1,\"foo, bar, baz\",\"foo bar baz\"\n\n" | sed '/^[[:space:]]*$/d' | ./csv2json.sh
[
    {
        "head1": 1,
        "head2": "foo, bar, baz",
        "head3": "foo bar baz"
    }
]

I haven't checked if there are any side effects on Linux now.

#!/bin/bash

# CSV to JSON converter using BASH
# original script from https://gist.github.com/dsliberty/3de707bc656cf757a0cb
# Usage ./csv2json.sh input.csv > output.json
#       cat <input.csv> | csv2json > output.json
#set -x
shopt -s extglob

input="${1:-/dev/stdin}"

SEP=","

[ -z "${input}" ] && echo "No CSV input file specified" && exit 1
[ ! -e "${input}" ] && echo "Unable to locate ${input}" && exit 1

csv_nextField()
{
    local line="$(echo "${1}" | sed 's/$(printf '\r')//g')"
    local start=0
    local stop=0

    if [[ -z "${line}" ]]; then
        return 0
    fi

    local offset=0
    local inQuotes=0
    while [[ -n "${line}" ]]; do
        local char="${line:0:1}"
        line="${line:1}"

        if [[ "${char}" == "${SEP}" && ${inQuotes} -eq 0 ]]; then
            inQuotes=0
            break
        elif [[ "${char}" == '"' ]]; then
            if [[ ${inQuotes} -eq 1 ]]; then
                inQuotes=0
            else
                inQuotes=1
            fi
        else
            echo -n "${char}"
        fi
        offset=$(( ${offset} + 1 ))
    done

    echo ""
    return $(( ${offset} + 1 ))
}

read -r first_line < "${input}"
a=0
headings=$(echo "${first_line}" | awk -F"${SEP}" {'print NF'})

if [ "${input}" = "/dev/stdin" ]; then
  while read -r line
  do
    lines_str+="$line"$'\n'
    c=1
  done < "${input}"
else
  lines_str="$(cat "${input}")"
  c=0
fi

lines_num=$(echo "${lines_str}" | wc -l)

while [[ ${a} -lt ${headings} ]]; do
    field="$(csv_nextField "${first_line}")"
    first_line="${first_line:${?}}"
    head_array[${a}]="${field}"
    a=$(( ${a} + 1 ))
done

#c=0
echo "["
while [ ${c} -lt ${lines_num} ]
do
    read -r each_line
    each_line="$(echo "${each_line}" | sed 's/$(printf '\r')//g')"

    if [[ ${c} -eq 0 ]]; then
        c=$(( ${c} + 1 ))
    else
        d=0
        echo "    {"
        while [[ ${d} -lt ${headings} ]]; do
            item="$(csv_nextField "${each_line}")"
            each_line="${each_line:${?}}"
            echo -n "        \"${head_array[${d}]}\": "
            case "${item}" in
                "")
                    echo -n "null"
                    ;;
                null|true|false|\"*\"|+([0123456789]))
                    echo -n ${item}
                    ;;
                *)
                    echo -n "\"${item}\""
                    ;;
            esac
            d=$(( ${d} + 1 ))
            [[ ${d} -lt ${headings} ]] && echo "," || echo ""
        done

        echo -n "    }"

        c=$(( ${c} + 1 ))
        [[ ${c} -lt ${lines_num} ]] && echo "," || echo ""
    fi

done <<< "${lines_str}"
echo "]"

@onkar-cliqr
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#!/bin/bash

CSV to JSON converter using BASH

Usage ./csv2json input.csv > output.json

input=$1
[ -z $1 ] && echo "No CSV input file specified" && exit 1
[ ! -e $input ] && echo "Unable to locate $1" && exit 1
read first_line < $input
a=0
headings=echo $first_line | awk -F, {'print NF'}
lines=cat $input | wc -l
while [ $a -lt $headings ]
do
head_array[$a]=$(echo $first_line | awk -v x=$(($a + 1)) -F"," '{print $x}' | tr -d '\r')
a=$(($a+1))
done
c=0
echo "["
while [ $c -le $lines ]
do
read each_line
if [ $c -ne 0 ]; then
d=0
echo -n "{"
while [ $d -lt $headings ]
do
each_element=$(echo $each_line | awk -v y=$(($d + 1)) -F"," '{print $y}' | tr -d '\r')
if [ $d -ne $(($headings-1)) ]; then
echo -n ""${head_array[$d]}":"$each_element","
else
echo -n ""${head_array[$d]}":"$each_element""
fi
d=$(($d+1))
done
if [ $c -eq $(($lines)) ]; then
echo "}"
else
echo "},"
fi
fi
c=$(($c+1))
done < $input
echo "]"

This should give with quatation and array of json objects

@jamie-cole70
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Question, the script runs fine but does not output a json file?

@idzob
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idzob commented Aug 5, 2020

Problem if field value have more than 254 characters.After that field every other field will the same

@mrabino1
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I have a field that has the following value
"doc":0000000000000000000000000000000000000000000000000000000000000000,
what is interesting is that the all zeros is failing to be parsed by JSON tools ...

they either want a 0 or a "0000000000000000000000000000000000000000000000000000000000000000"

Is there a way that we can put quotes around all values even if they are numbers? or is that outside the accepted formatting of JSON?

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