如何将 URL 数组作为函数的参数传递

Question

我想将第一个函数返回的一组 URL 传递到第二个函数中，但我不确定如何执行此操作。

require 'open-uri'
require 'nokogiri'
require 'byebug'

def fetch_recipe_urls
  base_url = 'https://cooking.nytimes.com'
  easy_recipe_url = 'https://cooking.nytimes.com/search?q=easy'
  easy_searchpage = Nokogiri::HTML(open(easy_recipe_url))
  recipes = easy_searchpage.search('//article[@class="card recipe-card"]/@data-url')
  recipes_url_array = recipes.map do |recipe|
    uri = URI.parse(recipe.text)
    uri.scheme = "http"
    uri.host = "cooking.nytimes.com"
    uri.query = nil
    uri.to_s
  end

end

def scraper(url)
  html_file = open(url).read
  html_doc = Nokogiri::HTML(html_file)
  recipes = Array.new
  recipe = {
    title: html_doc.css('h1.recipe-title').text.strip,
    time: html_doc.css('span.recipe-yield-value').text.split("servings")[1],
    steps: html_doc.css('ol.recipe-steps').text.split.join(" "),
    ingredients: html_doc.css('ul.recipe-ingredients').text.split.join(" ")
  }

  recipes << recipe
end

Answer 1

因为你在调用fetch_recipe_urls之后有一个数组，你可以迭代并为每个URL调用scraper：

def scraper(url)
  html_file = open(url).read
  html_doc = Nokogiri::HTML(html_file)

  {
    title: html_doc.css('h1.recipe-title').text.strip,
    time: html_doc.css('span.recipe-yield-value').text.split("servings")[1],
    steps: html_doc.css('ol.recipe-steps').text.split.join(" "),
    ingredients: html_doc.css('ul.recipe-ingredients').text.split.join(" ")
  }
end

fetch_recipe_urls.map { |url| scraper(url) }

但实际上我会将代码构造为：

BASE_URL = 'https://cooking.nytimes.com/'

def fetch_recipe_urls
  page = Nokogiri::HTML(open(BASE_URL + 'search?q=easy'))
  recipes = page.search('//article[@class="card recipe-card"]/@data-url')
  recipes.map { |recipe_node| BASE_URL + URI.parse(recipe_node.text).to_s }
end

def scrape(url)
  html_doc = Nokogiri::HTML(open(url).read)

  {
    title: html_doc.css('h1.recipe-title').text.strip,
    time: html_doc.css('span.recipe-yield-value').text.split("servings")[1],
    steps: html_doc.css('ol.recipe-steps').text.split.join(" "),
    ingredients: html_doc.css('ul.recipe-ingredients').text.split.join(" ")
  }
end

fetch_recipe_urls.map { |url| scrape(url) }

您也可以在 fetch_recipe_urls 中调用 scrape/scraper，但我建议采用单一职责方法。一个更好的主意是制作此 OOP 并构建一个 Scraper class 和一个 CookingRecipe 以使其更加惯用。

Answer 2

或者如果你想将数组传递给 scraper...

def fetch_recipe_urls
  ...
  recipes = scraper(recipes_url_array)
end


def scraper(urls)
  recipes = []
  urls.each do |url|
    html_file = open(url).read
    html_doc = Nokogiri::HTML(html_file)
    recipe = {
      title: html_doc.css('h1.recipe-title').text.strip,
      time: html_doc.css('span.recipe-yield-value').text.split("servings")[1],
      steps: html_doc.css('ol.recipe-steps').text.split.join(" "),
      ingredients: html_doc.css('ul.recipe-ingredients').text.split.join(" ")
    }
    recipes << recipe
  end
  recipes
end

如何将 URL 数组作为函数的参数传递

How to pass an array of URLs as a parameter for a function

ruby

arrays

nokogiri