add NPE check for request body

Author: ldetmer

java-bigquery/google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/telemetry/HttpTracingRequestInitializer.java

@@ -121,8 +121,10 @@ private static void addCommonResponseAttributesToSpan(
 
   static void addRequestBodySizeToSpan(HttpRequest request, Span span) {
     try {
-      span.setAttribute(HTTP_REQUEST_BODY_SIZE, request.getContent().getLength());
-    } catch (Exception e) {
+      if (request.getContent() != null) {
+        span.setAttribute(HTTP_REQUEST_BODY_SIZE, request.getContent().getLength());
+      }
+    } catch (IOException e) {
       // Ignore - body size not available
     }
   }

java-bigquery/google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/telemetry/HttpTracingRequestInitializerTest.java

@@ -218,6 +218,22 @@ public void testAddRequestBodySizeToSpan_ExceptionHandled() throws IOException {
     assertNull(span.getAttributes().get(HttpTracingRequestInitializer.HTTP_REQUEST_BODY_SIZE));
   }
 
+  @Test
+  public void testAddRequestBodySizeToSpan_NullBody() throws IOException {
+    HttpTransport transport = createTransport();
+    HttpRequest request = buildPostRequest(transport, null, BASE_URL, null);
+
+    HttpTracingRequestInitializer.addRequestBodySizeToSpan(request, parentSpan);
+
+    spanScope.close();
+    parentSpan.end();
+
+    List<SpanData> spans = spanExporter.getFinishedSpanItems();
+    assertEquals(1, spans.size());
+    SpanData span = spans.get(0);
+    assertNull(span.getAttributes().get(HttpTracingRequestInitializer.HTTP_REQUEST_BODY_SIZE));
+  }
+
   @Test
   public void testAddResponseBodySizeToSpan_NullLength() throws IOException {
     HttpTransport transport =