Changes to look ahead in isBatchedQuery (#62)

Simple change to ensure that the readlimit passed into InputStream.mark matches the length of the read buffer. This ensures that when InputStream.reset is called the stream is reset correctly. A test has also been added to ensure this behaviour.

Author: briancullen

src/main/java/graphql/servlet/GraphQLServlet.java

@@ -439,11 +439,12 @@ private boolean isBatchedQuery(InputStream inputStream) throws IOException {
  return false;
  }
 
+ final int BUFFER_LENGTH = 128;
  ByteArrayOutputStream result = new ByteArrayOutputStream();
- byte[] buffer = new byte[128];
+ byte[] buffer = new byte[BUFFER_LENGTH];
  int length;
 
- inputStream.mark(0);
+ inputStream.mark(BUFFER_LENGTH);
  while ((length = inputStream.read(buffer)) != -1) {
  result.write(buffer, 0, length);
  String chunk = result.toString();

src/test/groovy/graphql/servlet/GraphQLServletSpec.groovy

@@ -13,6 +13,8 @@ import org.springframework.mock.web.MockHttpServletResponse
 import spock.lang.Shared
 import spock.lang.Specification
 
+import javax.servlet.ServletInputStream
+import javax.servlet.http.HttpServletRequest
 /**
  * @author Andrew Potter
  */
@@ -715,4 +717,26 @@ class GraphQLServletSpec extends Specification {
  expect:
  servlet.getMapper().writeValueAsString(ExecutionTypeInfo.newTypeInfo().type(new GraphQLNonNull(Scalars.GraphQLString)).build()) != "{}"
  }
+
+ def "isBatchedQuery check uses buffer length as read limit"() {
+ setup:
+ HttpServletRequest mockRequest = Mock()
+ ServletInputStream mockInputStream = Mock()
+
+ mockInputStream.markSupported() >> true
+ mockRequest.getInputStream() >> mockInputStream
+ mockRequest.getMethod() >> "POST"
+
+ when:
+ servlet.doPost(mockRequest, response)
+
+ then:
+ 1 * mockInputStream.mark(128)
+
+ then:
+ 1 * mockInputStream.read({ it.length == 128 }) >> -1
+
+ then:
+ 1 * mockInputStream.reset()
+ }
 }