如何通过 Ruby on Rails 中的 API GET 请求访问（并保存到我的数据库）JSON 数组中的嵌套对象/属性？

Question

How can I access (and save to my postgresQL database) nested objects/properties within a JSON array via an API GET request in Ruby on Rails?

I have accessed all of the properties such as PropertyNumber etc. and this is saved to my database and I have it displaying on my front end. I also want to use the information to perform calculations etc. I can do this with all properties of the JSON object except for the ValuationReport property which contains nested objects.

The ValuationReport property appears to be an array object containing one or many ValuationReport objects (each containing 5 properties - Level, FloorUse, Area, NavPerM2 and Nav). I would like to access this information and save each individually to my database in the same way as I have done with the other properties. At the moment it seems to be saved to my database as an object or a string and is displaying on the front end like this:

[{"Level"=>"1", "FloorUse"=>"OFFICE(S)", "Area"=>23.89, "NavPerM2"=>70.0, "Nav"=>1672.3}, {"Level"=>"0", "FloorUse"=>"OFFICE(S)", "Area"=>74.57, "NavPerM2"=>100.0, "Nav"=>7457.0}]

Here's my seeds.rb file:

require 'rest-client'
require 'json'

# Define Method - API Request
def properties

    response = RestClient.get('https://api.valoff.ie/api/Property/GetProperties?Fields=*&LocalAuthority=CARLOW%20COUNTY%20COUNCIL&CategorySelected=OFFICE&Format=json&Download=false')
    json = JSON.parse(response)
    
    json.each do |property|
        puts "Creating property #{property['PropertyNumber']}"
        Property.create!(
            publication_date: property['PublicationDate'],
            property_number: property['PropertyNumber'],
            county: property['County'],
            local_authority: property['LocalAuthority'],
            valuation: property['Valuation'],
            category: property['Category'],
            uses: property['Uses'],
            address_1: property['Address1'],
            address_2: property['Address2'],
            address_3: property['Address3'],
            address_4: property['Address4'],
            address_5: property['Address5'],
            car_park: property['CarPark'],
            xitm: property['Xitm'],
            yitm: property['Yitm'],
            valuation_report: property['ValuationReport']
        )
    end
end

# Call Method
properties

Here's my schema.rb file:

  create_table "properties", force: :cascade do |t|
    t.string "publication_date"
    t.string "property_number"
    t.string "county"
    t.string "local_authority"
    t.string "valuation"
    t.string "category"
    t.string "uses"
    t.string "address_1"
    t.string "address_2"
    t.string "address_3"
    t.string "address_4"
    t.string "address_5"
    t.string "car_park"
    t.string "xitm"
    t.string "yitm"
    t.string "valuation_report"
    t.datetime "created_at", precision: 6, null: false
    t.datetime "updated_at", precision: 6, null: false
  end

I expect that I will need to add the 5 individual properties to my schema (Level, FloorUse, Area, NavPerM2 and Nav) in order to save them individually. Or maybe they can be accessed from the ValuationReport attribute and be parsed in a controller for calculations or in the html.erb file for clean display. I'm not sure about this.

Thank you for reading this and for your help.

Answer 1

This was resolved by creating a Property and then using its ID in Units:

require 'rest-client'
require 'json'

# Define Method - API Request
def properties

    response = RestClient.get('https://api.valoff.ie/api/Property/GetProperties?Fields=*&LocalAuthority=CAVAN%20COUNTY%20COUNCIL&CategorySelected=OFFICE&Format=csv&Download=false')
    json = JSON.parse(response)

    json.each do |property|
        puts "Creating property #{property['PropertyNumber']}"

        property_model = Property.create!(

            publication_date: property['PublicationDate'],
            property_number: property['PropertyNumber'],
            county: property['County'],
            local_authority: property['LocalAuthority'],
            valuation: property['Valuation'],
            category: property['Category'],
            uses: property['Uses'],
            address_1: property['Address1'],
            address_2: property['Address2'],
            address_3: property['Address3'],
            address_4: property['Address4'],
            address_5: property['Address5'],
            car_park: property['CarPark'],
            xitm: property['Xitm'],
            yitm: property['Yitm']
        )


        property['ValuationReport'].each do |unit|
          puts "Creating unit."
          property_model.units.create!(
            level: unit['Level'],
            floor_use: unit['FloorUse'],
            area: unit['Area'],
            nav_per_m2: unit['NavPerM2'],
            nav: unit['Nav']
          )
        end
    end
end

# Call Method
properties

Reference: Ruby on Rails: How can I use JSONPath to access (and save to database) nested objects/properties within a JSON array?