filter out cfn tags (#94)

Nextdoor · Mar 13, 2020 · b14378d · b14378d
1 parent b4af98f
commit b14378d
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Showing 2 changed files with 48 additions and 2 deletions.
diff --git a/core/src/main/java/com/nextdoor/bender/handler/BaseHandler.java b/core/src/main/java/com/nextdoor/bender/handler/BaseHandler.java
@@ -22,11 +22,13 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import org.apache.commons.io.FileUtils;
@@ -159,8 +161,16 @@ public void init(Context ctx) throws HandlerException {
      */
     if (config.getHandlerConfig().getIncludeFunctionTags()) {
       AWSLambda lambda = this.lambdaClientFactory.newInstance();
-      ListTagsResult res = lambda.listTags(new ListTagsRequest().withResource(ctx.getInvokedFunctionArn()));
-      monitor.addTagsMap(res.getTags());
+      ListTagsResult res =
+          lambda.listTags(new ListTagsRequest().withResource(ctx.getInvokedFunctionArn()));
+
+      monitor.addTagsMap(
+          /*
+           * Filter out tags that come from CloudFormation
+           */
+          res.getTags().entrySet().stream()
+              .filter(map -> !map.getKey().startsWith("aws:cloudformation"))
+              .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)));
     }
 
     /*

diff --git a/core/src/test/java/com/nextdoor/bender/handler/BaseHandlerTest.java b/core/src/test/java/com/nextdoor/bender/handler/BaseHandlerTest.java
@@ -293,6 +293,42 @@ public void tagsDuplicate() throws HandlerException {
     assertTrue(actual.entrySet().containsAll(expected.entrySet()));
   }
 
+  @Test
+  public void tagsCloudformation() throws HandlerException {
+    BaseHandler.CONFIG_FILE = "/config/handler_config_tags_duplicate.json";
+
+    TestContext context = new TestContext();
+    context.setInvokedFunctionArn("arn:aws:lambda:us-east-1:123:function:test:test_tags");
+
+    AWSLambdaClientFactory mockFactory = mock(AWSLambdaClientFactory.class);
+    AWSLambda mockLambda = mock(AWSLambda.class);
+    doReturn(mockLambda).when(mockFactory).newInstance();
+
+    ListTagsResult mockResult = mock(ListTagsResult.class);
+    HashMap<String, String> functionTags = new HashMap<String, String>() {
+      {
+        put("f1", "foo");
+        put("aws:cloudformation:foo", "foo");
+        put("aws:cloudformation:bar", "bar");
+      }
+    };
+    doReturn(functionTags).when(mockResult).getTags();
+    doReturn(mockResult).when(mockLambda).listTags(any());
+
+    handler.lambdaClientFactory = mockFactory;
+    handler.init(context);
+    Map<String, String> actual = handler.monitor.getTagsMap();
+
+    HashMap<String, String> expected = new HashMap<String, String>() {
+      {
+        put("f1", "foo");
+        put("u1", "bar");
+      }
+    };
+
+    assertTrue(actual.entrySet().containsAll(expected.entrySet()));
+  }
+
   @Test(expected = HandlerException.class)
   public void testBadConfig() throws HandlerException {
     BaseHandler.CONFIG_FILE = "/config/handler_config_bad.json";