Add --dry-run flag: DryRunCloudControllerClient and predicted-changes API

multiapps-controller-api/src/main/java/org/cloudfoundry/multiapps/controller/api/model/DryRunResult.java

@@ -0,0 +1,40 @@
+package org.cloudfoundry.multiapps.controller.api.model;
+
+import java.util.List;
+
+import org.immutables.value.Value;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
+@Value.Immutable
+@JsonSerialize(as = ImmutableDryRunResult.class)
+@JsonDeserialize(as = ImmutableDryRunResult.class)
+public interface DryRunResult {
+
+    @JsonProperty("appsToCreate")
+    List<String> getAppsToCreate();
+
+    @JsonProperty("appsToUpdate")
+    List<String> getAppsToUpdate();
+
+    @JsonProperty("appsToDelete")
+    List<String> getAppsToDelete();
+
+    @JsonProperty("servicesToCreate")
+    List<String> getServicesToCreate();
+
+    @JsonProperty("servicesToUpdate")
+    List<String> getServicesToUpdate();
+
+    @JsonProperty("servicesToDelete")
+    List<String> getServicesToDelete();
+
+    @JsonProperty("routesToCreate")
+    List<String> getRoutesToCreate();
+
+    @JsonProperty("routesToDelete")
+    List<String> getRoutesToDelete();
+
+}

multiapps-controller-api/src/main/java/org/cloudfoundry/multiapps/controller/api/model/Operation.java

@@ -100,6 +100,12 @@ public static List<State> getFinalStates() {
     @Nullable
     public abstract ErrorType getErrorType();
 
+    @Nullable
+    public abstract DryRunResult getDryRunResult();
+
+    @Nullable
+    public abstract Map<String, String> getOutputs();
+
     public abstract List<Message> getMessages();
 
     @AllowNulls

multiapps-controller-api/src/main/resources/mtarest.yaml

@@ -779,6 +779,14 @@ definitions:
         enum:
         - "CONTENT"
         - "INFRASTRUCTURE"
+      dryRunResult:
+        readOnly: true
+        $ref: "#/definitions/DryRunResult"
+      outputs:
+        type: "object"
+        readOnly: true
+        additionalProperties:
+          type: "string"
       messages:
         type: "array"
         readOnly: true
@@ -789,6 +797,49 @@ definitions:
         readOnly: true
         additionalProperties:
           type: "object"
+  DryRunResult:
+    type: "object"
+    properties:
+      appsToCreate:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      appsToUpdate:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      appsToDelete:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      servicesToCreate:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      servicesToUpdate:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      servicesToDelete:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      routesToCreate:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
+      routesToDelete:
+        type: "array"
+        readOnly: true
+        items:
+          type: "string"
   ProcessType:
     type: "object"
     properties:

multiapps-controller-process/src/main/java/org/cloudfoundry/multiapps/controller/process/client/DryRunChangeSet.java

@@ -0,0 +1,19 @@
+package org.cloudfoundry.multiapps.controller.process.client;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class DryRunChangeSet {
+
+    public List<String> appsCreate = new ArrayList<>();
+    public List<String> appsUpdate = new ArrayList<>();
+    public List<String> appsDelete = new ArrayList<>();
+    public List<String> servicesCreate = new ArrayList<>();
+    public List<String> servicesUpdate = new ArrayList<>();
+    public List<String> servicesDelete = new ArrayList<>();
+    public List<String> routesCreate = new ArrayList<>();
+    public List<String> routesDelete = new ArrayList<>();
+
+    public DryRunChangeSet() {
+    }
+}