jq – JSON Processor

jq is a lightweight command-line JSON processor. It slices, filters, maps, and transforms structured data with the same ease that sed, awk, and grep handle text.

Key Features

• Filter Language: Powerful JSON query syntax
• Transformation: Reshape JSON data
• Stream Processing: Handle large files
• Pretty Print: Format JSON output
• Zero Dependencies: Single binary

Installation

Install jq on Ubuntu:

sudo apt install jq

Usage Examples

Common jq operations:

# Pretty print
curl api.example.com/data | jq .

# Extract field
echo '{"name":"John","age":30}' | jq .name

# Filter array
echo '[{"id":1},{"id":2},{"id":3}]' | jq '.[] | select(.id > 1)'

# Transform data
echo '[{"name":"John"},{"name":"Jane"}]' | jq '[.[] | .name]'

# Multiple operations
cat data.json | jq '
  .items
  | map(select(.active))
  | sort_by(.date)
  | .[0:5]
'

Benefits

jq makes JSON manipulation trivial on the command line. Its powerful query language handles complex transformations that would require writing code in other contexts.

Download jq