json liquid filter

did committed Aug 17, 2015

commit 68d4a10e23b46fab2658566d36d6c3fa9ad2ef83

Showing 3 changed files with 110 additions and 0 deletions

locomotive/steam/liquid/filters/json.rb b/lib/locomotive/steam/liquid/filters/json.rb +42 -0

@@	@@ -0,0 +1,42 @@
+	module Locomotive
+	module Steam
+	module Liquid
+	module Filters
+	module Json
+
+	def json(input, fields = nil)
+	if fields && fields.is_a?(String)
+	fields = fields.split(',').map(&:strip)
+	end
+
+	if fields.blank?
+	input.to_json
+	elsif input.respond_to?(:each)
+	if fields.size == 1
+	input.map { \|object\| object[fields.first].to_json }.join(',')
+	else
+	input.map { \|object\| "{" + object_to_json(object, fields) + "}" }.join(',')
+	end
+	else
+	object_to_json(input, fields)
+	end
+	end
+
+	protected
+
+	def object_to_json(input, fields)
+	[].tap do \|output\|
+	fields.each do \|field\|
+	output << %("#{field}":#{input[field].to_json})
+	end
+	end.join(',')
+	end
+
+	end
+
+	::Liquid::Template.register_filter(Json)
+
+	end
+	end
+	end
+	end

spec/support/liquid.rb +11 -0

@@	@@ -9,6 +9,17 @@ def parse_template(source, options = nil)
	end

	module Liquid
+
+	class TestDrop < Liquid::Drop
+	def initialize(source)
+	@_source = source
+	end
+
+	def before_method(meth)
+	@_source[meth.to_sym]
+	end
+	end
+
	class SimpleEventsListener
	def initialize
	ActiveSupport::Notifications.subscribe(/^steam\.parse\./) do \|name, start, finish, id, payload\|

spec/unit/liquid/filters/json_spec.rb +57 -0

@@	@@ -0,0 +1,57 @@
+	require 'spec_helper'
+
+	describe Locomotive::Steam::Liquid::Filters::Json do
+
+	include Locomotive::Steam::Liquid::Filters::Json
+
+	let(:input) { nil }
+	subject { json(*input) }
+
+	describe 'adds quotes to a string' do
+
+	let(:input) { 'foo' }
+	it { expect(subject).to eq %("foo") }
+
+	end
+
+	context 'drop' do
+
+	describe 'includes only the fields specified' do
+
+	let(:input) { [Liquid::TestDrop.new(title: 'Acme', body: 'Lorem ipsum'), 'title'] }
+	it { expect(subject).to eq %("title":"Acme") }
+
+	end
+
+	end
+
+	context 'collections' do
+
+	describe 'adds brackets and quotes to a collection' do
+
+	let(:input) { [['foo', 'bar']] }
+	it { expect(subject).to eq %(["foo","bar"]) }
+
+	end
+
+	describe 'includes the first field' do
+
+	let(:input) {
+	[[Liquid::TestDrop.new(title: 'Acme', body: 'Lorem ipsum'),
+	Liquid::TestDrop.new(title: 'Hello world', body: 'Lorem ipsum')], 'title'] }
+	it { expect(subject).to eq %("Acme","Hello world") }
+
+	end
+
+	describe 'includes the specified fields' do
+
+	let(:input) {
+	[[Liquid::TestDrop.new(title: 'Acme', body: 'Lorem ipsum', date: '2013-12-13'),
+	Liquid::TestDrop.new(title: 'Hello world', body: 'Lorem ipsum', date: '2013-12-12')], 'title, body'] }
+	it { expect(subject).to eq %({"title":"Acme","body":"Lorem ipsum"},{"title":"Hello world","body":"Lorem ipsum"}) }
+
+	end
+
+	end
+
+	end