Handle the case HTTPClient doesn't yield block or body is nil

If HTTP response body is empty, HTTPClient doesn't yield given block,
and its response object's body attribute is nil.

lib/td/client/api.rb

@@ -289,6 +289,7 @@ def do_get(url, params=nil, &block)
         if block
           current_total_chunk_size = 0
           response = client.get(target, params, header) {|res, chunk|
+            break if res.status != 200
             current_total_chunk_size += chunk.bytesize
             block.call(res, chunk, current_total_chunk_size)
           }
@@ -300,17 +301,17 @@ def do_get(url, params=nil, &block)
         else
           response = client.get(target, params, header)
 
-          validate_content_length!(response, response.body.bytesize) if @ssl
-        end
+          status = response.code
+          # retry if the HTTP error code is 500 or higher and we did not run out of retrying attempts
+          if !block_given? && status >= 500 && cumul_retry_delay < @max_cumul_retry_delay
+            $stderr.puts "Error #{status}: #{get_error(response)}. Retrying after #{retry_delay} seconds..."
+            sleep retry_delay
+            cumul_retry_delay += retry_delay
+            retry_delay *= 2
+            redo # restart from beginning of do-while loop
+          end
 
-        status = response.code
-        # retry if the HTTP error code is 500 or higher and we did not run out of retrying attempts
-        if !block_given? && status >= 500 && cumul_retry_delay < @max_cumul_retry_delay
-          $stderr.puts "Error #{status}: #{get_error(response)}. Retrying after #{retry_delay} seconds..."
-          sleep retry_delay
-          cumul_retry_delay += retry_delay
-          retry_delay *= 2
-          redo # restart from beginning of do-while loop
+          validate_content_length!(response, response.body.to_s.bytesize) if @ssl
         end
       rescue Errno::ECONNREFUSED, Errno::ECONNRESET, Timeout::Error, EOFError,
         SystemCallError, OpenSSL::SSL::SSLError, SocketError, HTTPClient::TimeoutError,

lib/td/client/api/job.rb

@@ -272,6 +272,22 @@ def validate_content_length_with_range(response, current_total_chunk_size)
     end
   end
 
+  def validate_response_status(res, current_total_chunk_size=0)
+    case res.status
+    when 200
+      if current_total_chunk_size != 0
+        # try to resume but the server returns 200
+        raise_error("Get job result failed", res)
+      end
+    when 206 # resuming
+    else
+      if res.status/100 == 5
+        raise HTTPServerException
+      end
+      raise_error("Get job result failed", res)
+    end
+  end
+
   class HTTPServerException < StandardError
   end
 
@@ -297,43 +313,28 @@ def job_result_download(job_id, format='msgpack', autodecode=true)
     current_total_chunk_size = 0
     infl = nil
     begin # LOOP of Network/Server errors
-      response = nil
-      client.get(url, params, header) do |res, chunk|
-        unless response
-          case res.status
-          when 200
-            if current_total_chunk_size != 0
-              # try to resume but the server returns 200
-              raise_error("Get job result failed", res)
-            end
-          when 206 # resuming
-          else
-            if res.status/100 == 5
-              raise HTTPServerException
-            end
-            raise_error("Get job result failed", res)
-          end
-          if infl.nil? && autodecode
-            case res.header['Content-Encoding'][0].to_s.downcase
-            when 'gzip'
-              infl = Zlib::Inflate.new(Zlib::MAX_WBITS + 16)
-            when 'deflate'
-              infl = Zlib::Inflate.new
-            end
+      response = client.get(url, params, header) do |res, chunk|
+        validate_response_status(res, current_total_chunk_size)
+        if infl.nil? && autodecode
+          case res.header['Content-Encoding'][0].to_s.downcase
+          when 'gzip'
+            infl = Zlib::Inflate.new(Zlib::MAX_WBITS + 16)
+          when 'deflate'
+            infl = Zlib::Inflate.new
           end
         end
-        response = res
         current_total_chunk_size += chunk.bytesize
         chunk = infl.inflate(chunk) if infl
         yield chunk, current_total_chunk_size
       end
+      validate_response_status(response)
 
       # completed?
       validate_content_length_with_range(response, current_total_chunk_size)
     rescue Errno::ECONNREFUSED, Errno::ECONNRESET, Timeout::Error, EOFError,
       SystemCallError, OpenSSL::SSL::SSLError, SocketError, HTTPClient::TimeoutError,
       HTTPServerException => e
-      if response # at least a chunk is downloaded
+      if current_total_chunk_size > 0
         if etag = response.header['ETag'][0]
           header['If-Range'] = etag
           header['Range'] = "bytes=#{current_total_chunk_size}-"

spec/td/client/job_api_spec.rb

@@ -320,6 +320,27 @@
       expect(api.job_result(12345)).to eq ['hello', 'world']
     end
 
+    it '200 (blank) -> 200 works fine' do
+      i = 0
+      stub_api_request(:get, '/v3/job/result/12345').
+        with(:query => {'format' => 'msgpack'}).
+        to_return do
+        i += 1
+        puts "count : #{i}"
+        {
+          :headers => {
+            'Content-Length' => packed.bytesize,
+            'Etag' => '"abcdefghijklmn"',
+          },
+          :body => (i == 1 ? nil : packed)
+        }
+      end
+      expect(api).to receive(:sleep).once
+      expect($stderr).to receive(:print)
+      expect($stderr).to receive(:puts)
+      expect(api.job_result(12345)).to eq ['hello', 'world']
+    end
+
   end
 
   describe 'job_result_format' do