How can I pretty-print JSON in a shell script?

Pretty-printing JSON in shell scripts typically involves using command-line tools like jq. jq is a lightweight and flexible command-line JSON processor. If jq is installed on your system, you can use it to format JSON output.

Here's an example of how to pretty-print JSON in shell scripts using jq:

shell
#!/bin/bash

# Assume you have a JSON file named mydata.json
json_file="mydata.json"

# Use jq to pretty-print JSON content
jq '.' "$json_file"

If you obtain JSON output directly from a command, you can do the following:

shell
#!/bin/bash

# Assume you have a command that outputs JSON
json_output=$(some_command_that_outputs_json)

# Use jq to pretty-print
echo "$json_output" | jq '.'

If jq is not installed on your system and you cannot install it, you can use Python's json.tool module as an alternative. Most Linux systems include Python, making this a practical solution. Here's how to use Python to format JSON:

shell
#!/bin/bash

# Assume you have a JSON file named mydata.json
json_file="mydata.json"

# Use Python's json.tool module to pretty-print JSON content
python -m json.tool "$json_file"

Or, if the JSON data comes from the output of a command:

shell
#!/bin/bash

# Assume you have a command that outputs JSON
json_output=$(some_command_that_outputs_json)

# Use Python to pretty-print
echo "$json_output" | python -m json.tool

Using jq is the recommended approach as it not only formats JSON output but also performs complex queries, transformations, and data operations. In contrast, Python's json.tool is primarily intended for formatting.