Implement JsonParseHelper

Helpers.md

@@ -219,4 +219,10 @@ Truthiness of arguments is determined by [Handlebars.Utils.isEmpty(Object)](http
 ```handlebars
 {{#if (not (if a '===' b)) }} a does not equal b {{/if}}
 {{#not (if a '===' b) }} a does not equal b {{/not}}
+```
+
+### [JsonParser](light-development/src/main/java/com/merkle/oss/magnolia/renderer/handlebars/helpers/JsonParseHelper.java)
+Can be used to pass parsed json to other helpers. Arrays,objects and primitives are supported.
+```handlebars
+{{pattern name='somePattern' someJsonObjectProperty=(parse-json '{"key": "value"}')}}
 ```

light-development/pom.xml

@@ -37,6 +37,10 @@
             <groupId>com.google.auto.factory</groupId>
             <artifactId>auto-factory</artifactId>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+        </dependency>
 
         <!-- TESTING DEPENDENCIES -->
         <dependency>

light-development/src/main/java/com/merkle/oss/magnolia/renderer/handlebars/helpers/JsonParseHelper.java

@@ -0,0 +1,35 @@
+package com.merkle.oss.magnolia.renderer.handlebars.helpers;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import com.github.jknack.handlebars.Options;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonParser;
+
+public class JsonParseHelper implements NamedHelper<String> {
+	private final Gson gson = new GsonBuilder().create();
+
+	public Object apply(final String json, final Options options) throws IOException {
+		final JsonElement jsonElement = JsonParser.parseString(json);
+		if(jsonElement.isJsonArray()) {
+			return gson.fromJson(jsonElement.getAsJsonArray(), List.class);
+		}
+		if(jsonElement.isJsonObject()) {
+			return gson.fromJson(jsonElement.getAsJsonObject(), Map.class);
+		}
+		if(jsonElement.isJsonPrimitive()) {
+			return json;
+		}
+		return null;
+	}
+
+	@Override
+	public Set<String> names() {
+		return Set.of("parse-json");
+	}
+}