Base64 Decode & Encode Filters (#1450)

History.md

@@ -2,6 +2,9 @@
 
 ## 5.0.2 (unreleased)
 
+### Features
+* Add `base64_encode`, `base64_decode`, `base64_url_safe_encode`, and `base64_url_safe_decode` filters (#1450) [Daniel Insley]
+
 ### Fixes
 * Fix support for using a String subclass for the liquid source (#1421) [Dylan Thacker-Smith]
 

lib/liquid/standardfilters.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'cgi'
+require 'base64'
 require 'bigdecimal'
 
 module Liquid
@@ -63,6 +64,26 @@ module Liquid
       result
     end
 
+    def base64_encode(input)
+      Base64.strict_encode64(input.to_s)
+    end
+
+    def base64_decode(input)
+      Base64.strict_decode64(input.to_s)
+    rescue ::ArgumentError
+      raise Liquid::ArgumentError, "invalid base64 provided to base64_decode"
+    end
+
+    def base64_url_safe_encode(input)
+      Base64.urlsafe_encode64(input.to_s)
+    end
+
+    def base64_url_safe_decode(input)
+      Base64.urlsafe_decode64(input.to_s)
+    rescue ::ArgumentError
+      raise Liquid::ArgumentError, "invalid base64 provided to base64_url_safe_decode"
+    end
+
     def slice(input, offset, length = nil)
       offset = Utils.to_integer(offset)
       length = length ? Utils.to_integer(length) : 1

test/integration/standard_filter_test.rb

@@ -145,6 +145,40 @@ class StandardFiltersTest < Minitest::Test
     assert_equal('&lt;strong&gt;Hulk&lt;/strong&gt;', @filters.escape_once('&lt;strong&gt;Hulk</strong>'))
   end
 
+  def test_base64_encode
+    assert_equal('b25lIHR3byB0aHJlZQ==', @filters.base64_encode('one two three'))
+    assert_equal('', @filters.base64_encode(nil))
+  end
+
+  def test_base64_decode
+    assert_equal('one two three', @filters.base64_decode('b25lIHR3byB0aHJlZQ=='))
+
+    exception = assert_raises(Liquid::ArgumentError) do
+      @filters.base64_decode("invalidbase64")
+    end
+
+    assert_equal('Liquid error: invalid base64 provided to base64_decode', exception.message)
+  end
+
+  def test_base64_url_safe_encode
+    assert_equal(
+      'YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXogQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMTIzNDU2Nzg5MCAhQCMkJV4mKigpLT1fKy8_Ljo7W117fVx8',
+      @filters.base64_url_safe_encode('abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890 !@#$%^&*()-=_+/?.:;[]{}\|')
+    )
+    assert_equal('', @filters.base64_url_safe_encode(nil))
+  end
+
+  def test_base64_url_safe_decode
+    assert_equal(
+      'abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 1234567890 !@#$%^&*()-=_+/?.:;[]{}\|',
+      @filters.base64_url_safe_decode('YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXogQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVogMTIzNDU2Nzg5MCAhQCMkJV4mKigpLT1fKy8_Ljo7W117fVx8')
+    )
+    exception = assert_raises(Liquid::ArgumentError) do
+      @filters.base64_url_safe_decode("invalidbase64")
+    end
+    assert_equal('Liquid error: invalid base64 provided to base64_url_safe_decode', exception.message)
+  end
+
   def test_url_encode
     assert_equal('foo%2B1%40example.com', @filters.url_encode('foo+1@example.com'))
     assert_equal('1', @filters.url_encode(1))