From 41b3778d67296245675f41e17825aceca49eee49 Mon Sep 17 00:00:00 2001
From: Matthew Burgess <mattyb149@apache.org>
Date: Fri, 20 May 2022 13:37:58 -0400
Subject: [PATCH] NIFI-10044: Add content viewer support for YAML

This closes #6063

Signed-off-by: David Handermann <exceptionfactory@apache.org?
---
 .../nifi-standard-content-viewer/pom.xml      |  5 ++++
 .../web/StandardContentViewerController.java  | 23 +++++++++++++++++++
 .../src/main/resources/META-INF/NOTICE        |  6 ++++-
 .../main/webapp/META-INF/nifi-content-viewer  |  9 +++++++-
 4 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/pom.xml b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/pom.xml
index a0ecda0357..1c6e219add 100644
--- a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/pom.xml
+++ b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/pom.xml
@@ -79,5 +79,10 @@
             <groupId>org.xerial.snappy</groupId>
             <artifactId>snappy-java</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.yaml</groupId>
+            <artifactId>snakeyaml</artifactId>
+            <version>1.30</version>
+        </dependency>
     </dependencies>
 </project>
diff --git a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/java/org/apache/nifi/web/StandardContentViewerController.java b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/java/org/apache/nifi/web/StandardContentViewerController.java
index a02300f91c..f89a74f4e2 100644
--- a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/java/org/apache/nifi/web/StandardContentViewerController.java
+++ b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/java/org/apache/nifi/web/StandardContentViewerController.java
@@ -30,6 +30,8 @@ import org.apache.nifi.xml.processing.transform.StandardTransformProvider;
 import org.joda.time.DateTime;
 import org.joda.time.LocalDate;
 import org.joda.time.LocalTime;
+import org.yaml.snakeyaml.DumperOptions;
+import org.yaml.snakeyaml.Yaml;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
@@ -57,6 +59,13 @@ public class StandardContentViewerController extends HttpServlet {
         supportedMimeTypes.add("application/avro-binary");
         supportedMimeTypes.add("avro/binary");
         supportedMimeTypes.add("application/avro+binary");
+        supportedMimeTypes.add("text/x-yaml");
+        supportedMimeTypes.add("text/yaml");
+        supportedMimeTypes.add("text/yml");
+        supportedMimeTypes.add("application/x-yaml");
+        supportedMimeTypes.add("application/x-yml");
+        supportedMimeTypes.add("application/yaml");
+        supportedMimeTypes.add("application/yml");
     }
 
     /**
@@ -150,6 +159,20 @@ public class StandardContentViewerController extends HttpServlet {
                     formatted = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(objectJson);
 
                     contentType = "application/json";
+                } else if ("text/x-yaml".equals(contentType) || "text/yaml".equals(contentType) || "text/yml".equals(contentType)
+                        || "application/x-yaml".equals(contentType) || "application/x-yml".equals(contentType)
+                        || "application/yaml".equals(contentType) || "application/yml".equals(contentType)) {
+                    Yaml yaml = new Yaml();
+                    // Parse the YAML file
+                    final Object yamlObject = yaml.load(content.getContentStream());
+                    DumperOptions options = new DumperOptions();
+                    options.setIndent(2);
+                    options.setPrettyFlow(true);
+                    // Fix below - additional configuration
+                    options.setDefaultFlowStyle(DumperOptions.FlowStyle.BLOCK);
+                    Yaml output = new Yaml(options);
+                    formatted = output.dump(yamlObject);
+
                 } else {
                     // leave plain text alone when formatting
                     formatted = content.getContent();
diff --git a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/resources/META-INF/NOTICE b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/resources/META-INF/NOTICE
index b12860cb3d..c61dc15981 100644
--- a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/resources/META-INF/NOTICE
+++ b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/resources/META-INF/NOTICE
@@ -34,4 +34,8 @@ The following binary components are provided under the Apache Software License v
 
       This library containd statically linked libstdc++. This inclusion is allowed by
       "GCC RUntime Library Exception"
-      http://gcc.gnu.org/onlinedocs/libstdc++/manual/license.html
\ No newline at end of file
+      http://gcc.gnu.org/onlinedocs/libstdc++/manual/license.html
+
+  (ASLv2) SnakeYAML
+      The following NOTICE information applies:
+        Copyright (c) 2008, https://www.snakeyaml.org
\ No newline at end of file
diff --git a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/webapp/META-INF/nifi-content-viewer b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/webapp/META-INF/nifi-content-viewer
index f105ca2f0b..3e17ff63a5 100644
--- a/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/webapp/META-INF/nifi-content-viewer
+++ b/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-content-viewer/src/main/webapp/META-INF/nifi-content-viewer
@@ -19,4 +19,11 @@ text/plain
 text/csv
 avro/binary
 application/avro-binary
-application/avro+binary
\ No newline at end of file
+application/avro+binary
+text/x-yaml
+text/yaml
+text/yml
+application/x-yaml
+application/x-yml
+application/yaml
+application/yml
\ No newline at end of file