SDK-Issues : Refactoring the code to render as CloudEvent and schema validation

.github/linters/sun_checks.xml

@@ -92,7 +92,9 @@
     <module name="InvalidJavadocPosition"/>
     <module name="JavadocMethod"/>
     <module name="JavadocType"/>
-    <module name="JavadocVariable"/>
+    <module name="JavadocVariable">
+  	<property name="scope" value="public"/>
+    </module>
     <module name="JavadocStyle"/>
     <module name="MissingJavadocMethod"/>
     <!-- Enables @SuppressWarnings Support                -->
@@ -135,7 +137,12 @@
     <module name="MethodParamPad"/>
     <module name="NoWhitespaceAfter"/>
     <module name="NoWhitespaceBefore"/>
-    <module name="OperatorWrap"/>
+    <module name="OperatorWrap">
+      <property name="tokens"
+     value="ASSIGN,DIV_ASSIGN,PLUS_ASSIGN,MINUS_ASSIGN,STAR_ASSIGN,MOD_ASSIGN,
+            SR_ASSIGN,BSR_ASSIGN,SL_ASSIGN,BXOR_ASSIGN,BOR_ASSIGN,BAND_ASSIGN"/>
+      <property name="option" value="eol"/>
+    </module>
     <module name="ParenPad"/>
     <module name="TypecastParenPad"/>
     <module name="WhitespaceAfter"/>

pom.xml

@@ -117,6 +117,19 @@
 			<version>2.0.6</version>
 		</dependency>
 
+		<dependency>
+			<groupId>com.fasterxml.jackson.datatype</groupId>
+			<artifactId>jackson-datatype-jsr310</artifactId>
+			<version>2.14.2</version>
+		</dependency>
+
+		<dependency>
+			<groupId>com.networknt</groupId>
+			<artifactId>json-schema-validator</artifactId>
+			<version>1.0.78</version>
+		</dependency>
+
+
 	</dependencies>
 	<build>
 		<pluginManagement>

src/main/java/dev/cdevents/CDEvents.java

@@ -0,0 +1,92 @@
+package dev.cdevents;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.networknt.schema.JsonSchema;
+import com.networknt.schema.JsonSchemaFactory;
+import com.networknt.schema.SpecVersion;
+import com.networknt.schema.ValidationMessage;
+import dev.cdevents.config.CustomObjectMapper;
+import dev.cdevents.exception.CDEventsException;
+import dev.cdevents.models.CDEvent;
+import io.cloudevents.CloudEvent;
+import io.cloudevents.core.v03.CloudEventBuilder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.charset.StandardCharsets;
+import java.time.OffsetDateTime;
+import java.util.Set;
+import java.util.UUID;
+
+public final class CDEvents {
+
+    private CDEvents() {
+    }
+
+    private static ObjectMapper objectMapper = new CustomObjectMapper().customConfiguration();
+    private static Logger log = LoggerFactory.getLogger(CDEvents.class);
+
+
+    /**
+     * @param cdEvent
+     * @return json string of a cdEvent
+     */
+    public static String cdEventAsJson(CDEvent cdEvent) {
+        try {
+            return objectMapper.writeValueAsString(cdEvent);
+        } catch (JsonProcessingException e) {
+            log.error("Error while mapping cdEvent as Json {}", e.getMessage());
+            throw new CDEventsException("Error while mapping cdEvent as Json {}", e);
+        }
+    }
+
+
+    /**
+     * Creates a CloudEvent from the cdEvent.
+     * @param cdEvent
+     * @return CloudEvent
+     */
+    public static CloudEvent cdEventAsCloudEvent(CDEvent cdEvent) {
+
+        String cdEventJson = cdEventAsJson(cdEvent);
+        if (!validateCDEvent(cdEvent)) {
+            log.error("CDEvent validation failed against schema URL - {}", cdEvent.schemaURL());
+            throw new CDEventsException("CDEvent validation failed against schema URL - " + cdEvent.schemaURL());
+        }
+        CloudEvent ceToSend = new CloudEventBuilder()
+                .withId(UUID.randomUUID().toString())
+                .withSource(cdEvent.getContext().getSource())
+                .withType(cdEvent.getContext().getType())
+                .withDataContentType("application/json")
+                .withData(cdEventJson.getBytes(StandardCharsets.UTF_8))
+                .withTime(OffsetDateTime.now())
+                .build();
+
+        return ceToSend;
+    }
+
+    /**
+     * Validates the cdEvent against the Schema URL.
+     * @param cdEvent
+     * @return valid cdEvent
+     */
+    public static boolean validateCDEvent(CDEvent cdEvent) {
+        String cdEventJson = cdEventAsJson(cdEvent);
+
+        JsonSchemaFactory factory = JsonSchemaFactory.getInstance(SpecVersion.VersionFlag.V202012);
+        JsonSchema jsonSchema = factory.getSchema(cdEvent.eventSchema());
+
+        JsonNode jsonNode = objectMapper.convertValue(cdEvent, ObjectNode.class);
+        Set<ValidationMessage> errors = jsonSchema.validate(jsonNode);
+
+        if (!errors.isEmpty()) {
+            log.error("CDEvent validation failed with errors {}", errors);
+            return false;
+        }
+        return true;
+    }
+
+}

src/main/java/dev/cdevents/config/CustomObjectMapper.java

@@ -0,0 +1,20 @@
+package dev.cdevents.config;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+
+public class CustomObjectMapper extends ObjectMapper {
+
+    /**
+     * @return customized ObjectMapper
+     */
+    public ObjectMapper customConfiguration() {
+        return this
+                .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
+                .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
+                .configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false)
+                .registerModule(new JavaTimeModule());
+    }
+}

src/main/java/dev/cdevents/config/package-info.java

@@ -0,0 +1,17 @@
+/**
+ * Copyright 2023-Present https://cdevents.dev/
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ *
+ */
+
+package dev.cdevents.config;