Netflix · abasiri · Apr 3, 2014 · Apr 3, 2014
diff --git a/src/main/java/com/netflix/simianarmy/basic/chaos/BasicChaosMonkey.java b/src/main/java/com/netflix/simianarmy/basic/chaos/BasicChaosMonkey.java
@@ -300,13 +300,23 @@ && noTerminationInLastWindow(group, mandatoryTerminationWindowInDays)) {
             }
         }
         propName = "probability";
-        String defaultProp = NS + group.type();
-        String probProp = NS + group.type() + "." + group.name() + "." + propName;
-        double prob = cfg.getNumOrElse(probProp, cfg.getNumOrElse(defaultProp + "." + propName, 1.0));
+        double prob = getNumFromCfgOrDefault(group, propName, 1.0);
         LOGGER.info("Group {} [type {}] enabled [prob {}]", new Object[]{group.name(), group.type(), prob});
         return prob;
     }
 
+    protected double getNumFromCfgOrDefault(InstanceGroup group, String propName, double defaultValue) {
+        String defaultProp = String.format("%s%s.%s", NS, group.type(), propName);
+        String prop = String.format("%s%s.%s.%s", NS, group.type(), group.name(), propName);
+        return cfg.getNumOrElse(prop, cfg.getNumOrElse(defaultProp, defaultValue));
+    }
+
+    protected boolean getBoolFromCfgOrDefault(InstanceGroup group, String propName, boolean defaultValue) {
+        String defaultProp = String.format("%s%s.%s", NS, group.type(), propName);
+        String prop = String.format("%s%s.%s.%s", NS, group.type(), group.name(), propName);
+        return cfg.getBoolOrElse(prop, cfg.getBoolOrElse(defaultProp, defaultValue));
+    }
+
     /**
      * Returns lastOptInTimeInMilliseconds from the .properties file.
      *
@@ -344,11 +354,12 @@ && getPreviousTerminationCount(group, windowStart.getTime()) <= 0) {
      * @return boolean
      */
     protected boolean isGroupEnabled(InstanceGroup group) {
-        String prop = NS + group.type() + "." + group.name() + ".enabled";
-        String defaultProp = NS + group.type() + ".enabled";
-        if (cfg.getBoolOrElse(prop, cfg.getBool(defaultProp))) {
+        boolean enabled = getBoolFromCfgOrDefault(group, "enabled", false);
+        if (enabled) {
             return true;
         } else {
+            String prop = NS + group.type() + "." + group.name() + ".enabled";
+            String defaultProp = NS + group.type() + ".enabled";
             LOGGER.info("Group {} [type {}] disabled, set {}=true or {}=true",
                     new Object[]{group.name(), group.type(), prop, defaultProp});
             return false;
@@ -417,10 +428,9 @@ private Event terminateInstance(InstanceGroup group, String inst, ChaosType chao
     protected boolean isMaxTerminationCountExceeded(InstanceGroup group) {
         Validate.notNull(group);
         String propName = "maxTerminationsPerDay";
-        String defaultProp = String.format("%s%s.%s", NS, group.type(), propName);
-        String prop = String.format("%s%s.%s.%s", NS, group.type(), group.name(), propName);
-        double maxTerminationsPerDay = cfg.getNumOrElse(prop, cfg.getNumOrElse(defaultProp, 1.0));
+        double maxTerminationsPerDay = getNumFromCfgOrDefault(group, propName, 1.0);
         if (maxTerminationsPerDay <= MIN_MAX_TERMINATION_COUNT_PER_DAY) {
+            String prop = String.format("%s%s.%s.%s", NS, group.type(), group.name(), propName);
             LOGGER.info("ChaosMonkey is configured to not allow any killing from group {} [{}] "
                     + "with max daily count set as {}", new Object[]{group.name(), group.type(), prop});
             return true;

diff --git a/src/test/java/com/netflix/simianarmy/basic/chaos/TestBasicChaosMonkey.java b/src/test/java/com/netflix/simianarmy/basic/chaos/TestBasicChaosMonkey.java
@@ -23,6 +23,7 @@
 
 import javax.ws.rs.core.Response;
 
+import com.netflix.simianarmy.GroupType;
 import org.testng.Assert;
 import org.testng.annotations.Test;
 
@@ -35,6 +36,10 @@
 
 // CHECKSTYLE IGNORE MagicNumberCheck
 public class TestBasicChaosMonkey {
+    private enum GroupTypes implements GroupType {
+        TYPE_A, TYPE_B
+    };
+
     @Test
     public void testDisabled() {
         TestChaosMonkeyContext ctx = new TestChaosMonkeyContext("disabled.properties");
@@ -353,6 +358,33 @@ public void testMaxTerminationCountPerDayGroupLevel() {
         Assert.assertEquals(ctx.terminated().size(), 3);
     }
 
+    @Test
+    public void testGetValueFromCfgWithDefault() {
+        TestChaosMonkeyContext ctx = new TestChaosMonkeyContext("propertiesWithDefaults.properties");
+        BasicChaosMonkey chaos = new BasicChaosMonkey(ctx);
+
+        // named 1 has actual values in config
+        InstanceGroup named1 = new BasicInstanceGroup("named1", GroupTypes.TYPE_A, "test-dev-1");
+
+        // named 2 doesn't have values but it's group has values
+        InstanceGroup named2 = new BasicInstanceGroup("named2", GroupTypes.TYPE_A, "test-dev-1");
+
+        // named 3 doesn't have values and it's group doesn't have values
+        InstanceGroup named3 = new BasicInstanceGroup("named3", GroupTypes.TYPE_B, "test-dev-1");
+
+        Assert.assertEquals(chaos.getBoolFromCfgOrDefault(named1, "enabled", true), false);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named1, "probability", 3.0), 1.1);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named1, "maxTerminationsPerDay", 4.0), 2.1);
+
+        Assert.assertEquals(chaos.getBoolFromCfgOrDefault(named2, "enabled", true), true);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named2, "probability", 3.0), 1.0);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named2, "maxTerminationsPerDay", 4.0), 2.0);
+
+        Assert.assertEquals(chaos.getBoolFromCfgOrDefault(named3, "enabled", true), true);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named3, "probability", 3.0), 3.0);
+        Assert.assertEquals(chaos.getNumFromCfgOrDefault(named3, "maxTerminationsPerDay", 4.0), 4.0);
+    }
+
     @Test
     public void testMandatoryTerminationDisabled() {
         TestChaosMonkeyContext ctx = new TestChaosMonkeyContext("mandatoryTerminationDisabled.properties");

diff --git a/src/test/resources/com/netflix/simianarmy/chaos/propertiesWithDefaults.properties b/src/test/resources/com/netflix/simianarmy/chaos/propertiesWithDefaults.properties
@@ -0,0 +1,7 @@
+simianarmy.chaos.leashed = false
+simianarmy.chaos.TYPE_A.enabled = true
+simianarmy.chaos.TYPE_A.probability = 1.0
+simianarmy.chaos.TYPE_A.maxTerminationsPerDay = 2.0
+simianarmy.chaos.TYPE_A.named1.enabled = false
+simianarmy.chaos.TYPE_A.named1.probability = 1.1
+simianarmy.chaos.TYPE_A.named1.maxTerminationsPerDay = 2.1