How to create/generate a JSON file dynamically using shell script.

In this post, we will see that, how we can dynamically generate/create a JSON file using shell script.

Some days back, i was having a scenario where i need to generate a JSON file in a docker container using environment variable. And environment variable values are passed through the environment file into the docker container.

Will start with writing a shell/bash script. Lets name it, generate.sh

#!/bin/ash

cat > /home/app/secrets/account.json << EOF

{
  "type": $type,
  "project_id": $project_id,
  "private_key":$private_key,
  "client_email":$client_email,
  "client_id":$client_id,
  "auth_uri":$auth_uri,
  "token_uri":$token_uri
}


EOF

And we can now save this file. Where $type,$project_id,$private_key are the environment variables.

Now, we can run this shell script by executing the following command in the bash.

sh generate.sh

And this will generate a JSON file in the /home/app/secrets/ folder.

In the shebang, i have used #!/bin/ash as, i was using the alpine docker image.