tldr/pages/common/jq.md

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# jq
> A lightweight and flexible command-line JSON processor.
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> More information: <https://stedolan.github.io/jq>.
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- Output a JSON file, in pretty-print format:
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`jq . {{file.json}}`
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- Output all elements from arrays (or all key-value pairs from objects) in a JSON file:
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`jq .[] {{file.json}}`
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- Read JSON objects from a file into an array, and output it (inverse of `jq .[]`):
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`jq --slurp . {{file.json}}`
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- Output the first element in a JSON file:
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`jq .[0] {{file.json}}`
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- Output the value of a given key of the first element in a JSON text from stdin:
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`cat {{file.json}} | jq .[0].{{key_name}}`
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- Output the value of a given key of each element in a JSON text from stdin:
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`cat {{file.json}} | jq 'map(.{{key_name}})'`
- Combine multiple filters:
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`cat {{file.json}} | jq 'unique | sort | reverse'`
- Output the value of a given key to a string (and disable JSON output):
`cat {{file.json}} | jq --raw-output '"some text: \(.{{key_name}})"'`