FEATURE: implement body streaming for Net::HTTP

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+# 3.23.1 (future)
+
+  * Add support for streaming responses in Net::HTTP adapter
+
 # 3.23.0
 
  * Fixed HTTP.rb adapter to support streaming real responses when WebMock is enabled.

README.md

@@ -453,6 +453,24 @@ stub_request(:any, 'www.example.net').to_timeout
 RestClient.post('www.example.net', 'abc')    # ===> RestClient::RequestTimeout
 ```
 
+### Streaming response
+
+Net::HTTP supports streaming responses. WebMock can simulate this by specifying an Array for body.
+This is only implemented for Net::HTTP at the moment.
+
+```ruby
+stub_http_request(:get, "www.example.com").to_return(body: ["a", "b", "c"])
+
+Net::HTTP.start('www.example.com') do |http|
+  req = Net::HTTP::Get.new('/')
+  http.request(req) do |res|
+    res.read_body do |segment|
+      puts segment
+    end
+  end
+end    # ===> "a\nb\nc\n"
+```
+
 ### Multiple responses for repeated requests
 
 ```ruby

lib/webmock/http_lib_adapters/net_http_response.rb

@@ -25,7 +25,11 @@ def read_body(dest = nil, &block)
       return nil if @body.nil?
 
       dest ||= ::Net::ReadAdapter.new(block)
-      dest << @body.dup
+      if @body.is_a?(Array)
+        @body.each { |part| dest << part.dup }
+      else
+        dest << @body.dup
+      end
       @body = dest
     ensure
       # allow subsequent calls to #read_body to proceed as normal, without our hack...

spec/acceptance/net_http/net_http_spec.rb

@@ -142,6 +142,21 @@ class TestMarshalingInWebMockNetHTTP
     expect(response_body).to eq("abc")
   end
 
+  it "should support streaming a response body", focus: true do
+    stub_http_request(:get, "www.example.com").to_return(body: ["a", "b", "c"])
+    response_body = +""
+
+    http_request(:get, "http://www.example.com/") do |response|
+      i = 0
+      response.read_body do |fragment|
+        response_body << "#{fragment}#{i}"
+        i += 1
+      end
+    end
+
+    expect(response_body).to eq("a0b1c2")
+  end
+
   it "should handle Net::HTTP::Post#body" do
     stub_http_request(:post, "www.example.com").with(body: "my_params").to_return(body: "abc")
     req = Net::HTTP::Post.new("/")