implemented rule action modification

java/com.sap.sse.landscape.aws/src/com/sap/sse/landscape/aws/ApplicationLoadBalancer.java

@@ -148,4 +148,6 @@ public interface ApplicationLoadBalancer<ShardingKey> extends Named {
     RuleCondition createHostHeaderRuleCondition(String hostname);
     
     java.util.Collection<Rule> getRulesForTargetGroups(Iterable<TargetGroup<ShardingKey>> targetGroups);
+
+    Iterable<Rule> replaceTargetGroupInForwardRules(TargetGroup<ShardingKey> oldTargetGroup, TargetGroup<ShardingKey> newTargetGroup );
 }

java/com.sap.sse.landscape.aws/src/com/sap/sse/landscape/aws/AwsLandscape.java

@@ -517,6 +517,8 @@ public interface AwsLandscape<ShardingKey> extends Landscape<ShardingKey> {
     Iterable<Rule> getLoadBalancerListenerRules(Listener loadBalancerListener, Region region);
     
     public Iterable<Rule> modifyRuleConditions(Region region, Rule rule);
+    
+    public Iterable<Rule> modifyRuleActions(Region region, Rule rule);
 
     /**
      * Use {@link Rule.Builder} to create {@link Rule} objects you'd like to set for the {@link Listener} passed as parameter.

java/com.sap.sse.landscape.aws/src/com/sap/sse/landscape/aws/impl/ApplicationLoadBalancerImpl.java

@@ -31,6 +31,7 @@ import software.amazon.awssdk.services.elasticloadbalancingv2.model.RedirectActi
 import software.amazon.awssdk.services.elasticloadbalancingv2.model.Rule;
 import software.amazon.awssdk.services.elasticloadbalancingv2.model.RuleCondition;
 import software.amazon.awssdk.services.elasticloadbalancingv2.model.RulePriorityPair;
+import software.amazon.awssdk.services.elasticloadbalancingv2.model.TargetGroupTuple;
 
 public class ApplicationLoadBalancerImpl<ShardingKey>
 implements ApplicationLoadBalancer<ShardingKey> {
@@ -395,6 +396,41 @@ implements ApplicationLoadBalancer<ShardingKey> {
         }
         return ret;
     }
+    
+    /**
+     * Goes through all rules in this load balancer and replaces every target group in a forward-action that has the
+     * same ARN as the {@code oldTargetgroup} with the {@code newTargetgroup}
+     */
+    @Override
+    public Iterable<Rule> replaceTargetGroupInForwardRules(TargetGroup<ShardingKey> oldTargetGroup,
+            TargetGroup<ShardingKey> newTargetGroup) {
+        Iterable<Rule> rules = getRules();
+        Collection<Rule> modifiedRules = new ArrayList<>();
+        for (Rule r : rules) {
+            int i = 0;
+            boolean modified = false;
+            Action[] newActions = new Action[r.actions().size()];
+            for (Action a : r.actions()) {
+                if (a.forwardConfig() != null && a.targetGroupArn().equals(oldTargetGroup.getTargetGroupArn())) {
+                    newActions[i++] = createForwardToTargetGroupAction(newTargetGroup);
+                    modified = true;
+                } else {
+                    newActions[i++] = a;
+                }
+            }
+            if(modified) {
+                landscape.modifyRuleActions(region, Rule.builder().actions(newActions).ruleArn(r.ruleArn()).build())
+                    .forEach(t -> modifiedRules.add(t));
+            }
+        }
+        return modifiedRules;
+    }
+    
+    private Action createForwardToTargetGroupAction(TargetGroup<ShardingKey> targetGroup) {
+        return Action.builder().type(ActionTypeEnum.FORWARD).forwardConfig(fc -> fc
+                .targetGroups(TargetGroupTuple.builder().targetGroupArn(targetGroup.getTargetGroupArn()).build()))
+                .build();
+    }
 }
 
     

java/com.sap.sse.landscape.aws/src/com/sap/sse/landscape/aws/impl/AwsLandscapeImpl.java

@@ -2039,4 +2039,11 @@ public class AwsLandscapeImpl<ShardingKey> implements AwsLandscape<ShardingKey>
     public long getDNSTTLInSeconds() {
        return DEFAULT_DNS_TTL_SECONDS;
     }
+
+    @Override
+    public Iterable<Rule> modifyRuleActions(com.sap.sse.landscape.Region region, Rule rule) {
+        ModifyRuleResponse res = getLoadBalancingClient(getRegion(region))
+                .modifyRule(t -> t.actions(rule.actions()).ruleArn(rule.ruleArn()).build());
+        return res.rules();
+    }
 }