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@kristopherjohnson
Last active May 14, 2024 23:13
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Read JSON from standard input and writes formatted JSON to standard output. Requires Node.js.
#!/usr/bin/env node
// Reads JSON from stdin and writes equivalent
// nicely-formatted JSON to stdout.
var stdin = process.stdin,
stdout = process.stdout,
inputChunks = [];
stdin.resume();
stdin.setEncoding('utf8');
stdin.on('data', function (chunk) {
inputChunks.push(chunk);
});
stdin.on('end', function () {
var inputJSON = inputChunks.join(),
parsedData = JSON.parse(inputJSON),
outputJSON = JSON.stringify(parsedData, null, ' ');
stdout.write(outputJSON);
stdout.write('\n');
});
@danthegoodman
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Here's a oneliner that does the same thing (at least in mac and linux land, not sure about windows):

node -p 'JSON.stringify(JSON.parse(fs.readFileSync(0)),null,2)'

notably, JSON.parse can work off of a buffer and fs.readFileSync(0) reads the zero file descriptor, which is standard input.
Then, node -p is a way to execute and log the output from a statement. You could also write it with a node -e 'console.log(...)' if you would rather be in control of when or how the logging happens.

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