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Comment by ruuda | Hacker News Reader

If like me you can do basic queries in jq, but as soon as it gets slightly more complex (e.g. filter objects where some nested property that may not exist has a particular value), you wish you could do it with familiar Python/Rust/Javascript-like expressions and map/filter, try https://rcl-lang.org/#intuitive-json-queries.

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If you want it in your actual preferred language, it's usually pretty easy to throw something together.

E.g. Ruby:

    require 'json'
    script = ARGV.pop
    $J = JSON.parse(ARGF.read)
    puts JSON.pretty_generate(eval(script))

Lets you do:

curl --silent https://api.vultr.com/v2/regions | ./jr '$J["regions" ].find{_1["id"]=="nrt"}'

To translate their example ( curl --silent https://api.vultr.com/v2/regions | rcl query input.regions.key_by(r => r.id).nrt )

(... if you want to commit evil monkey-patching sins:

    #!/usr/bin/env ruby

    require 'json'
    
    class Hash
      def method_missing(sym) = (((r = self.dig(sym.to_s)) and return r) or super)
    end

    script = ARGV.pop
    $J = JSON.parse(ARGF.read)
    script = "$J#{script}" if script.start_with?(".")
    puts JSON.pretty_generate(eval(script))

Now you can do:

   curl --silent https://api.vultr.com/v2/regions | ./jr '.regions.find{_1.id =="nrt"}'

Or the more direct parallel:

   curl --silent https://api.vultr.com/v2/regions | ./jr '.regions.group_by{_1.id}.nrt'

Since I used ARGF, you either need to quote the script or avoid spaces; you could explicitly use STDIN instead, in which case it's marginally safer to skip the quotes, at the cost of not being able to give a filename as the last argument

)

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