What is the best way to parse JSON Object?

Help & Support
1

Hello friends!

Im trying to parse JSON, and dont know how to do it correct?
There is my code:

require "http/client"
require "json"

# do requests
def do_req
  response = HTTP::Client.get "https://api.caiyunapp.com/v2.5/96Ly7wgKGq6FhllM/116.391912,40.010711/weather.jsonp?hourlysteps=120&random=#{Random.rand}"
  raise "HTTP error: #{response.status_code}" unless response.status_code == 200

  response.body
end

JSON.parse(do_req).as_a.each do |idx|
  puts idx["result"]
end

So, I need to get all “keys” and “values”, should I make smth like JSON.mapping?
Thx in advance

2

If the response’s structure is well defined and known ahead of time, you could leverage JSON::Serializable - Crystal 1.4.1. Otherwise what you’re doing is fine, and is required for dynamic JSON data.

Another thing you could do is use the block version of HTTP::Client.get such that you don’t need to load the whole response body into memory, but can deserialize it in a streaming fashion. Ultimately this would look like:

require "http/client"
require "json"

data = HTTP::Client.get "https://api.caiyunapp.com/v2.5/96Ly7wgKGq6FhllM/116.391912,40.010711/weather.jsonp?hourlysteps=120&random=#{Random.rand}" do |resp|
  JSON.parse(resp.body_io).as_h["result"].as_h
end

pp data

Your code was erroring since you’re using .as_a when the data is in fact a hash, so using as_h would return a hash of the data within the result object. From here if you wanted to access the hourly description you could do data["hourly"].as_h["description"].as_s.

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3

wow friend, big thx!)

4

It’ nice to see another Chinese here.

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