jq is a powerful tool that lets you read, filter, and write JSON in bash The most useful bash commands for front end development While. This is the first part of an ongoing. 2) Updating TTL (Time-To-Live) column. sh. We then map over the array twice, first selecting the displayName, then selecting the value, giving us two arrays with just the values of those keys. . Lucky, there is jq , a command-line JSON processor. , , , , , . . .