Merge pull request #80 from dlecocq/master

Support for S3::Object#stream

lib/s3/object.rb

@@ -89,6 +89,12 @@ def content(reload = false)
       @content
     end
 
+    # Streams the content of the object without caching it, providing
+    # successive chunks to the block
+    def stream(options = {}, &block)
+      get_object(options, &block)
+    end
+
     # Saves the object, returns true if successfull.
     def save
       put_object
@@ -180,9 +186,9 @@ def copy_object(options = {})
       object
     end
 
-    def get_object(options = {})
+    def get_object(options = {}, &block)
       response = object_request(:get, options)
-      parse_headers(response)
+      parse_headers(response, &block)
     end
 
     def object_headers(options = {})
@@ -245,7 +251,7 @@ def dump_headers
       headers
     end
 
-    def parse_headers(response)
+    def parse_headers(response, &block)
       @metadata = response.to_hash.select { |k, v| k.to_s.start_with?("x-amz-meta") }
       self.etag = response["etag"] if response.key?("etag")
       self.content_type = response["content-type"] if response.key?("content-type")
@@ -257,7 +263,11 @@ def parse_headers(response)
         self.size = response["content-range"].sub(/[^\/]+\//, "").to_i
       else
         self.size = response["content-length"]
-        self.content = response.body
+        if block.nil?
+          self.content = response.body
+        else
+          response.read_body(nil, &block)
+        end
       end
     end
   end

test/object_test.rb

@@ -15,6 +15,7 @@ def setup
     @object_mac.content = "test2"
 
     @response_binary = Net::HTTPOK.new("1.1", "200", "OK")
+    @response_binary.stubs(:read_body).multiple_yields(*%w{t e s t})
     @response_binary.stubs(:body).returns("test".respond_to?(:force_encoding) ? "test".force_encoding(Encoding::BINARY) : "test")
     @response_binary["etag"] = ""
     @response_binary["content-type"] = "image/png"
@@ -133,6 +134,21 @@ def setup
     assert @object_lena.content(true)
   end
 
+  test "streaming" do
+    @object_lena.expects(:object_request).with(:get, {}).returns(@response_binary)
+
+    expected = /test/n
+    io = StringIO.new
+    @object_lena.stream do |chunk|
+      io.write(chunk)
+    end
+    io.seek(0)
+    actual = io.read
+    assert_match expected, actual
+    assert_equal "image/png", @object_lena.content_type
+    assert_equal @object.instance_variable_defined?(:@content), false
+  end
+
   test "retrieve" do
     @object_lena.expects(:object_request).with(:head, {}).returns(@response_binary)
     assert @object_lena.retrieve

test/test_helper.rb

@@ -1,3 +1,4 @@
 require "test/unit"
+require "stringio"
 require "mocha"
 require "s3"