How to convert yaml to csv file format?

I need to write bash script which takes yaml file:

first:John
last:Smith
first:David
last:Bennet

and convert it to csv file:

John,Smith
David,Bennet

Any ideas? Thanks!

4 Answers

You will find a complete library for it and you can easily use it, YAML2CSV... see github , here is the link provided.

Here is an awk command:

awk -v RS="first:|last:" '{gsub("first:|last:","",$0);print $1","$2}' RS='' infile.txt

Output is as you are expecting:

John,Smith
David,Bennet

Using sed and Miller () and running:

<input.yaml sed -r 's/:/ /g' | mlr --x2c -N cat >output.csv

you will have

John,Smith
David,Bennet

Please note: your input file is not a valid yaml.

You can use sed command to do this conversion :

 <file.yaml sed 's/first://g' | sed ':a;N;$!ba;s/\nlast:/,/g' | sed -r '/^\s*$/d' > file.csv

Explanation :

• <file.yaml is the input file (here, your YAML file to convert)
• sed 's/first://g' would remove each first: string list character
• sed ':a;N;$!ba;s/\nlast:/,/g' do almost same thing as previous command, but all options are used to detect newlines character which are previous last: string character lists (and replace that with a comma,`); see this StackOverflow answer more further details
• sed -r '/^\s*$/d' would remove each empty lines left, see this StackOverflow answer for more details
• > file.csv would redirect result into a new .csv file (if this file didn't exist, it would be created automatically), as conversion is finished

Result :

John,Smith
David,Bennet

Create your own script which will able to convert any .yaml file to .csv file. In my example, my script is named YAMLtoCSV.sh :

#! /bin/bash
if [ ${1#*.} = "yaml" ]
then <$1 sed 's/first://g' | sed ':a;N;$!ba;s/\nlast:/,/g' | sed -r '/^\s*$/d' > ${1%%.*}.csv echo "Conversion from" $1 "to" ${1%%.*}.csv "done"
else echo "This file didn't have YAML extension"
fi

and to execute it (don't forget to make the script executable with the command sudo chmod +x YAMLtoCSV.sh) :

./YAMLtoCSV.sh /home/<user>/file.yaml

You would get a file named file.csv next to your .yaml file, so his path is /home/<user>/file.csv

Note that I added an if statement in order to prevent file conversion error (which won't destroy any data, but would create some useless other data)