Added ExclusionStrategy to be used when serializing command reports.

src/main/java/io/testproject/sdk/internal/rest/AgentClient.java

@@ -25,6 +25,7 @@
 import io.testproject.sdk.internal.reporting.inferrers.GenericInferrer;
 import io.testproject.sdk.internal.reporting.inferrers.InferrerFactory;
 import io.testproject.sdk.internal.rest.messages.*;
+import io.testproject.sdk.internal.rest.serialization.DriverExclusionStrategy;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.exception.ExceptionUtils;
@@ -116,7 +117,7 @@ public final class AgentClient implements Closeable {
     /**
      * An instance of the Google JSON serializer to serialize and deserialize objects.
      */
-    private static final Gson GSON = new GsonBuilder().create();
+    private static final Gson GSON = new GsonBuilder().setExclusionStrategies(new DriverExclusionStrategy()).create();
 
     /**
      * Reports executor service with a single thread.
@@ -701,7 +702,13 @@ public boolean reportCommand(final Command command, final Object result, final b
         // Prepare payload
         DriverCommandReport report =
                 new DriverCommandReport(command.getName(), command.getParameters(), result, passed);
-        StringEntity entity = new StringEntity(GSON.toJson(report), StandardCharsets.UTF_8);
+        String json;
+        try {
+            json = GSON.toJson(report);
+        } catch (Exception e) {
+            return false;
+        }
+        StringEntity entity = new StringEntity(json, StandardCharsets.UTF_8);
         httpPost.setEntity(entity);
 
         // Send POST request

src/main/java/io/testproject/sdk/internal/rest/serialization/DriverExclusionStrategy.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2020 TestProject LTD. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.testproject.sdk.internal.rest.serialization;
+
+import com.google.gson.ExclusionStrategy;
+import com.google.gson.FieldAttributes;
+import org.openqa.selenium.WebDriver;
+
+/**
+ * This exclusion strategy makes sure to skip serialization of any classes implementing the WebDriver interface.
+ * Since this object is redundant when reporting command parameters and doesn’t pass serialization - we exclude it.
+ * See https://github.com/google/gson/issues/1540 for more details on the serialization problem
+ */
+public class DriverExclusionStrategy implements ExclusionStrategy {
+
+
+    /**
+     * Determines whether the class implements a {@link WebDriver} interface and should be ignored.
+     *
+     * @param clazz the class object that is under test
+     * @return true if the class should be ignored; otherwise false
+     */
+    @Override
+    public boolean shouldSkipClass(final Class<?> clazz) {
+        return WebDriver.class.isAssignableFrom(clazz);
+    }
+
+    /**
+     * Determined whether a filed should be skipped.
+     * It has no effect in this exclusion strategy as there is no need for it.
+     * Note: It is not used / implemented in this strategy as it is redundant.
+     *
+     * @param f the field object that is under test
+     * @return true if the field should be ignored; otherwise false
+     */
+    @Override
+    public boolean shouldSkipField(final FieldAttributes f) {
+        return false;
+    }
+}

src/main/java/io/testproject/sdk/internal/rest/serialization/package-info.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2020 TestProject LTD. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Serialization utility classes.
+ */
+package io.testproject.sdk.internal.rest.serialization;