Throw a friendly exception for old (selenium 2) nodeConfig.json files (#2838)

Author: mach6

java/server/src/org/openqa/grid/internal/utils/configuration/GridNodeConfiguration.java

@@ -68,6 +68,11 @@ public class GridNodeConfiguration extends GridConfiguration {
   @Expose( serialize = false )
   String remoteHost;
 
+  // used to read a Selenium 2.x nodeConfig.json file and throw a friendly exception
+  @Expose( serialize = false )
+  @Deprecated
+  private Object configuration;
+
   /*
    * config parameters which serialize and deserialize to/from json
    */
@@ -293,6 +298,14 @@ public static GridNodeConfiguration loadFromJSON(JsonObject json) {
       GridNodeConfiguration config =
         builder.excludeFieldsWithoutExposeAnnotation().create().fromJson(json, GridNodeConfiguration.class);
 
+      if (config.configuration != null) {
+        // caught below
+        throw new GridConfigurationException("Deprecated -nodeConfig file encountered. Please update"
+                                             + " the file to work with Selenium 3. See https://github.com"
+                                             + "/SeleniumHQ/selenium/wiki/Grid2#configuring-the-nodes-by-json"
+                                             + " for more details.");
+}
+
       return config;
     } catch (Throwable e) {
       throw new GridConfigurationException("Error with the JSON of the config : " + e.getMessage(),

java/server/test/org/openqa/grid/internal/utils/configuration/GridNodeConfigurationTest.java

@@ -29,6 +29,7 @@
 import com.beust.jcommander.JCommander;
 
 import org.junit.Test;
+import org.openqa.grid.common.exception.GridConfigurationException;
 import org.openqa.selenium.remote.DesiredCapabilities;
 
 import java.util.Arrays;
@@ -63,6 +64,20 @@ public void testLoadFromJson() {
     assertEquals(5L, gnc.capabilities.get(0).getCapability("maxInstances"));
   }
 
+  @Test(expected = GridConfigurationException.class)
+  public void testLoadFromOldJson() {
+    final String configJson = "{"
+                            + "\"configuration\":"
+                            + " {"
+                            + "\"host\": \"dummyhost\","
+                            + "\"maxSession\": 5,"
+                            + "\"port\": 1234"
+                            + " }"
+                            + "}";
+    JsonObject json = new JsonParser().parse(configJson).getAsJsonObject();
+    GridNodeConfiguration gnc = GridNodeConfiguration.loadFromJSON(json);
+  }
+
   @Test
   public void testDefaults() {
     GridNodeConfiguration gnc = new GridNodeConfiguration();