Support output errors (#249)

Signed-off-by: Charith Ellawala <charith@cerbos.dev>

Signed-off-by: Charith Ellawala <charith@cerbos.dev>

Author: charithe

src/main/java/dev/cerbos/sdk/CheckResult.java

@@ -47,14 +47,15 @@ public boolean isAllowed(String action) {
             return false;
         }
 
-        return this.entry.getActionsMap().getOrDefault(action, EffectOuterClass.Effect.EFFECT_DENY)
-                == EffectOuterClass.Effect.EFFECT_ALLOW;
+        return this.entry.getActionsMap().getOrDefault(action,
+                EffectOuterClass.Effect.EFFECT_DENY) == EffectOuterClass.Effect.EFFECT_ALLOW;
     }
 
     /**
      * Return all actions and effects in this instance.
      *
-     * @return Map of action to boolean indicating whether the action is allowed or not
+     * @return Map of action to boolean indicating whether the action is allowed or
+     *         not
      */
     public Map<String, Boolean> getAll() {
         if (this.entry == null) {
@@ -83,7 +84,8 @@ public boolean hasValidationErrors() {
     /**
      * Returns the list of validation errors if there are any.
      *
-     * @return List of {@link dev.cerbos.api.v1.schema.SchemaOuterClass.ValidationError}
+     * @return List of
+     *         {@link dev.cerbos.api.v1.schema.SchemaOuterClass.ValidationError}
      */
     public List<SchemaOuterClass.ValidationError> getValidationErrors() {
         if (this.entry == null) {
@@ -170,11 +172,54 @@ public int size() {
          * @return Map of output rule names and {@link Value}
          */
         public Map<String, Value> asMap() {
-            return this.outputs.stream().collect(Collectors.toUnmodifiableMap(Engine.OutputEntry::getSrc, Engine.OutputEntry::getVal));
+            return this.outputs.stream()
+                    .collect(Collectors.toUnmodifiableMap(Engine.OutputEntry::getSrc, Engine.OutputEntry::getVal));
+        }
+
+        /**
+         * Returns the output entries as a map keyed by rule name.
+         *
+         * @return Map of output rule names and {@link Entry}
+         */
+        public Map<String, Entry> entriesAsMap() {
+            return this.outputs.stream()
+                    .collect(Collectors.toUnmodifiableMap(Engine.OutputEntry::getSrc, (entry) -> {
+                        return new Entry(entry.getSrc(), entry.getVal(), entry.getAction(), entry.getError());
+                    }));
         }
 
         public List<Engine.OutputEntry> getRaw() {
             return this.outputs;
         }
+
+        public static final class Entry {
+            private final String source;
+            private final Value value;
+            private final String action;
+            private final Optional<String> error;
+
+            Entry(String source, Value value, String action, String error) {
+                this.source = source;
+                this.value = value;
+                this.action = action;
+                this.error = Optional.ofNullable(error);
+            }
+
+            public String getSource() {
+                return source;
+            }
+
+            public Value getValue() {
+                return value;
+            }
+
+            public String getAction() {
+                return action;
+            }
+
+            public Optional<String> getError() {
+                return error;
+            }
+        }
     }
 }

src/test/java/dev/cerbos/sdk/CerbosClientTests.java

@@ -11,6 +11,7 @@
 import com.google.protobuf.util.Values;
 import dev.cerbos.api.v1.engine.Engine;
 import dev.cerbos.api.v1.response.Response;
+import dev.cerbos.sdk.CheckResult.Outputs.Entry;
 import dev.cerbos.sdk.builders.AuxData;
 import dev.cerbos.sdk.builders.Principal;
 import dev.cerbos.sdk.builders.Resource;
@@ -196,9 +197,13 @@ public void checkResources() {
         Response.CheckResourcesResponse.ResultEntry.Meta.EffectMeta res1DeferMeta = res1DeferMetaOpt.get();
         Assertions.assertEquals("resource.leave_request.v20210210", res1DeferMeta.getMatchedPolicy());
 
-        Map<String, Value> res1Outputs = res1.getOutputs().asMap();
+        Map<String, Entry> res1Outputs = res1.getOutputs().entriesAsMap();
         Assertions.assertEquals(1, res1Outputs.size());
-        Value res1ViewOutput = res1Outputs.get("resource.leave_request.v20210210#public-view");
+        Entry res1ViewOutputEntry = res1Outputs.get("resource.leave_request.v20210210#public-view");
+        Assertions.assertNotNull(res1ViewOutputEntry);
+        Assertions.assertEquals("view:public", res1ViewOutputEntry.getAction());
+
+        Value res1ViewOutput = res1ViewOutputEntry.getValue();
         Assertions.assertNotNull(res1ViewOutput);
         Assertions.assertEquals(res1ViewOutput, Values.of(Struct.newBuilder()
                 .putFields("pID", Values.of("john"))