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Which way is better to
handle JSON with Crystal
@ariarijp
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Today’s Lightning talk
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The idea from
ཬ.rb 1st anniversary
https://nishinipporirb.doorkeeper.jp/events/25958
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I talked about
my first Crystal program
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Parse JSON using Crystal
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I compared
Ruby and Crystal
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Crystal is awesome.
But I don’t like
Java like type casting
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Next morning
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@asterite commented
on my repository
(Amazingly, @asterite read Japanese!)
https://github.com/ariarijp/ninirb-1st-anniversary-lt-crystal/commit/2d0062c4a1dc4cabaeb6884591c1771d768c0ce8
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As a result
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The legacy way
require "http/client"
require "json"
place = ARGV[0]
url = "http://api.openweathermap.org/data/2.5/weather?q=#{place}"
resp = HTTP::Client.get(url)
weather = JSON.parse(resp.body)
pp (((weather as Hash)["weather"] as Array)[0] as Hash)["main"]
puts "-" * 80
pp weather
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Crystal way
require "http/client"
require "json"
class WeatherResponse
json_mapping({
weather: Array(Weather),
})
class Weather
json_mapping({
id: Int32,
main: String,
description: String,
icon: String,
})
end
end
place = ARGV[0]
url = "http://api.openweathermap.org/data/2.5/weather?q=#{place}"
resp = HTTP::Client.get(url)
puts "-" * 80
weather_resp = WeatherResponse.from_json(resp.body)
pp weather_resp
pp weather_resp.weather[0].main
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Use JSON Mapping!
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Crystal is Awesome!
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end