Fix handling of EOF in Client#readpartial

lib/http/client.rb

@@ -55,11 +55,7 @@ def perform(req, options)
 
       req.stream @socket
 
-      begin
-        read_more BUFFER_SIZE until @parser.headers
-      rescue IOError, Errno::ECONNRESET, Errno::EPIPE => ex
-        raise IOError, "problem making HTTP request: #{ex}"
-      end
+      read_headers!
 
       body = Response::Body.new(self)
       res  = Response.new(@parser.status_code, @parser.http_version, @parser.headers, body, uri)
@@ -70,13 +66,22 @@ def perform(req, options)
     end
 
     # Read a chunk of the body
+    #
+    # @return [String] data chunk
+    # @return [Nil] when no more data left
     def readpartial(size = BUFFER_SIZE)
       return unless @socket
 
-      read_more size
+      begin
+        read_more size
+        finished = @parser.finished?
+      rescue EOFError
+        finished = true
+      end
+
       chunk = @parser.chunk
 
-      finish_response if @parser.finished?
+      finish_response if finished
 
       chunk.to_s
     end
@@ -133,6 +138,14 @@ def make_request_body(opts, headers)
       end
     end
 
+    # Reads data from socket up until headers
+    def read_headers!
+      read_more BUFFER_SIZE until @parser.headers
+    rescue IOError, Errno::ECONNRESET, Errno::EPIPE => ex
+      return if ex.is_a?(EOFError) && @parser.headers
+      raise IOError, "problem making HTTP request: #{ex}"
+    end
+
     # Callback for when we've reached the end of a response
     def finish_response
       @socket.close if @socket && !@socket.closed?

spec/http/client_spec.rb

@@ -158,11 +158,6 @@ def simple_response(body, status = 200)
       client.get(test_endpoint).to_s
     end
 
-    it 'fails on unexpected eof' do
-      expect { client.get("#{test_endpoint}/eof").to_s }
-        .to raise_error(IOError)
-    end
-
     context 'with HEAD request' do
       it 'does not iterates through body' do
         expect(client).to_not receive(:readpartial)
@@ -175,6 +170,63 @@ def simple_response(body, status = 200)
       end
     end
 
+    context 'when server closes connection unexpectedly' do
+      before do
+        socket_spy = double
+
+        allow(socket_spy).to receive(:close) { nil }
+        allow(socket_spy).to receive(:closed?) { true }
+        allow(socket_spy).to receive(:readpartial) { chunks.shift.call }
+        allow(socket_spy).to receive(:<<) { nil }
+
+        allow(TCPSocket).to receive(:open) { socket_spy }
+      end
+
+      context 'during headers reading' do
+        let :chunks do
+          [
+            proc { "HTTP/1.1 200 OK\r\n" },
+            proc { "Content-Type: text/html\r" },
+            proc { fail EOFError }
+          ]
+        end
+
+        it 'raises IOError' do
+          expect { client.get test_endpoint }.to raise_error IOError
+        end
+      end
+
+      context 'after headers were flushed' do
+        let :chunks do
+          [
+            proc { "HTTP/1.1 200 OK\r\n" },
+            proc { "Content-Type: text/html\r\n\r\n" },
+            proc { 'unexpected end of f' },
+            proc { fail EOFError }
+          ]
+        end
+
+        it 'reads partially arrived body' do
+          res = client.get(test_endpoint).to_s
+          expect(res).to eq 'unexpected end of f'
+        end
+      end
+
+      context 'when body and headers were flushed in one chunk' do
+        let :chunks do
+          [
+            proc { "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\nunexpected end of f" },
+            proc { fail EOFError }
+          ]
+        end
+
+        it 'reads partially arrived body' do
+          res = client.get(test_endpoint).to_s
+          expect(res).to eq 'unexpected end of f'
+        end
+      end
+    end
+
     context 'when server fully flushes response in one chunk' do
       before do
         socket_spy = double

spec/support/example_server/servlet.rb

@@ -74,10 +74,6 @@ def do_#{method.upcase}(req, res)
       res['Location'] = "http://#{ExampleServer::ADDR}/"
     end
 
-    get '/eof' do |req, _res|
-      req.instance_variable_get('@socket').close
-    end
-
     post '/form' do |req, res|
       if 'testing-form' == req.query['example']
         res.status = 200