Fix #546 CapturingInterceptor will now buffer response

hapi-fhir-base/src/main/java/ca/uhn/fhir/rest/client/interceptor/CapturingInterceptor.java

@@ -23,6 +23,11 @@
 import ca.uhn.fhir.rest.client.IClientInterceptor;
 import ca.uhn.fhir.rest.client.api.IHttpRequest;
 import ca.uhn.fhir.rest.client.api.IHttpResponse;
+import ca.uhn.fhir.rest.server.exceptions.InternalErrorException;
+import org.apache.http.HttpEntity;
+import org.apache.http.HttpResponse;
+
+import java.io.IOException;
 
 /**
  * Client interceptor which simply captures request and response objects and stores them so that they can be inspected after a client
@@ -55,8 +60,23 @@ public void interceptRequest(IHttpRequest theRequest) {
 	}
 
 	@Override
-	public void interceptResponse(IHttpResponse theRequest) {
-		myLastResponse = theRequest;
+	public void interceptResponse(IHttpResponse theResponse) {
+		//Buffer the reponse to avoid errors when content has already been read and the entity is not repeatable
+		try {
+			if(theResponse.getResponse() instanceof HttpResponse) {
+				HttpEntity entity = ((HttpResponse) theResponse.getResponse()).getEntity();
+				if( entity != null && !entity.isRepeatable()){
+					theResponse.bufferEntity();
+				}
+			} else {
+				theResponse.bufferEntity();
+			}
+		} catch (IOException e) {
+			throw new InternalErrorException("Unable to buffer the entity for capturing", e);
+		}
+
+
+		myLastResponse = theResponse;
 	}
 
 }

hapi-fhir-structures-dstu/src/test/java/ca/uhn/fhir/rest/client/CapturingInterceptorTest.java

@@ -0,0 +1,147 @@
+package ca.uhn.fhir.rest.client;
+
+import ca.uhn.fhir.rest.client.apache.ApacheHttpResponse;
+import ca.uhn.fhir.rest.client.api.IHttpRequest;
+import ca.uhn.fhir.rest.client.api.IHttpResponse;
+import ca.uhn.fhir.rest.client.interceptor.CapturingInterceptor;
+import ca.uhn.fhir.rest.server.exceptions.InternalErrorException;
+import org.apache.commons.io.IOUtils;
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
+import org.apache.http.HttpVersion;
+import org.apache.http.entity.BasicHttpEntity;
+import org.apache.http.entity.InputStreamEntity;
+import org.apache.http.entity.StringEntity;
+import org.apache.http.message.BasicHttpRequest;
+import org.apache.http.message.BasicHttpResponse;
+import org.junit.After;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.mockito.Spy;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.*;
+
+
+public class CapturingInterceptorTest {
+
+    @Rule
+    public ExpectedException thrown = ExpectedException.none();
+
+
+    @Test
+    public void testRequest() {
+        IHttpRequest expectedRequest = mock(IHttpRequest.class);
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptRequest(expectedRequest);
+
+        assertEquals(expectedRequest, interceptor.getLastRequest());
+    }
+
+    @Test
+    public void testResponse() throws Exception {
+        IHttpResponse expectedResponse = mock(IHttpResponse.class);
+        doNothing().when(expectedResponse).bufferEntity();
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(expectedResponse);
+
+        assertEquals(expectedResponse, interceptor.getLastResponse());
+        verify(expectedResponse).bufferEntity();
+    }
+
+    @Test
+    public void testResponseException() throws Exception {
+        IHttpResponse response = mock(IHttpResponse.class);
+        IOException expectedCause = new IOException();
+        doThrow(expectedCause).when(response).bufferEntity();
+
+        thrown.expect(InternalErrorException.class);
+        thrown.expectMessage("Unable to buffer the entity for capturing");
+        thrown.expectCause(equalTo(expectedCause));
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(response);
+    }
+
+    @Test
+    public void testResponseBufferApache() throws Exception{
+        HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, "OK");
+        response.setEntity(new InputStreamEntity(IOUtils.toInputStream("Some content", Charset.defaultCharset())));
+        IHttpResponse expectedResponse = spy(new ApacheHttpResponse(response));
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(expectedResponse);
+        IHttpResponse actualResponse = interceptor.getLastResponse();
+
+        assertEquals(expectedResponse, actualResponse);
+        assertThat("Some content", equalTo(IOUtils.toString(actualResponse.createReader())));
+        verify(expectedResponse).bufferEntity();
+
+        //A second call should not throw an exception (InpuStreamEntity is not repeatable)
+        IOUtils.toString(actualResponse.createReader());
+    }
+
+    @Test
+    public void testResponseRepeatable() throws Exception{
+        HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_OK, "OK");
+        response.setEntity(new StringEntity("Some content"));
+        IHttpResponse expectedResponse = spy(new ApacheHttpResponse(response));
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(expectedResponse);
+        IHttpResponse actualResponse = interceptor.getLastResponse();
+
+        assertEquals(expectedResponse, actualResponse);
+        assertThat("Some content", equalTo(IOUtils.toString(actualResponse.createReader())));
+        verify(expectedResponse, times(0)).bufferEntity();
+
+        //A second call should not throw an exception (StringEntity is repeatable)
+        IOUtils.toString(actualResponse.createReader());
+    }
+
+    @Test
+    public void testResponseBufferOther() throws Exception {
+        Object response = mock(Object.class);
+        IHttpResponse expectedResponse = mock(IHttpResponse.class);
+        when(expectedResponse.getResponse()).thenReturn(response);
+        doNothing().when(expectedResponse).bufferEntity();
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(expectedResponse);
+        IHttpResponse actualResponse = interceptor.getLastResponse();
+
+        assertEquals(expectedResponse, actualResponse);
+        verify(expectedResponse).bufferEntity();
+    }
+
+    @Test
+    public void testClear(){
+        IHttpRequest expectedRequest = mock(IHttpRequest.class);
+        IHttpResponse expectedResponse = mock(IHttpResponse.class);
+        Object response = mock(Object.class);
+        when(expectedResponse.getResponse()).thenReturn(response);
+
+        CapturingInterceptor interceptor = new CapturingInterceptor();
+        interceptor.interceptResponse(expectedResponse);
+        interceptor.interceptRequest(expectedRequest);
+
+        assertEquals(expectedRequest, interceptor.getLastRequest());
+        assertEquals(expectedResponse, interceptor.getLastResponse());
+
+        interceptor.clear();
+
+        assertNull(interceptor.getLastRequest());
+        assertNull(interceptor.getLastResponse());
+    }
+
+}