Class: Cache

Inherits:
Object
  • Object
show all
Defined in:
lib/utils/cache.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(path:) ⇒ Cache

Returns a new instance of Cache.



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# File 'lib/utils/cache.rb', line 5

def initialize(path:)
	@config = {
		:path => path
	}

	@size = File.readable?(@config[:path]) ? JSON.parse(File.read(@config[:path]).to_s)["data"].count : 0

	@last_fetched = File.readable?(@config[:path]) ? JSON.parse(File.read(@config[:path]).to_s)["last_fetched"] : nil
end

Instance Attribute Details

#last_fetched ⇒ Object

Returns the value of attribute last_fetched.



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# File 'lib/utils/cache.rb', line 3

def last_fetched
  @last_fetched
end

#size ⇒ Object

Returns the value of attribute size.



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# File 'lib/utils/cache.rb', line 3

def size
  @size
end

Instance Method Details

#add_entries_to_file(data:) ⇒ Object 



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# File 'lib/utils/cache.rb', line 43

def add_entries_to_file(data:)
	cache = self.read_from_file
	new_entries_count = 0

	# If an entry doesn't exist in the cache, we add it.
	data.each do |new_entry|
		unless cache["data"].find_index { |cache_entry| cache_entry["id"] == new_entry["id"] }
			cache["data"].push (new_entry.filter { |key| key != "content" })
			new_entries_count += 1
		end
	end

	self.size = cache["data"].count
	self.last_fetched = Date.today
	self.write_to_file data: cache

	puts "#{new_entries_count} new entries were written to cache."
end

#read_from_file ⇒ Object 



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# File 'lib/utils/cache.rb', line 15

def read_from_file
	if File.readable? @config[:path]
		JSON.parse(File.read(@config[:path]).to_s)
	else
		return {
			"size" => 0,
			"last_fetched" => nil,
			"data" => Array.new
		}
	end
end

#remove_entries_from_file(ids:) ⇒ Object 



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# File 'lib/utils/cache.rb', line 27

def remove_entries_from_file(ids:)
	cache = self.read_from_file

	ids.each do |id|
		# TODO We could implement a search algo like binary search for performance here
		cache["data"].each do |cached_entry|
			if cached_entry["id"].to_i == id.to_i
				cache["data"].delete cached_entry
			end
		end
	end

	self.size = cache["data"].count
	self.write_to_file data: cache
end

#write_to_file(data:) ⇒ Object 



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# File 'lib/utils/cache.rb', line 62

def write_to_file(data:)
	data["size"] = @size
	data["last_fetched"] = @last_fetched
	File.write(@config[:path], data.to_json)
end