Rework the Event interface

api/pom.xml

@@ -23,47 +23,40 @@
         <version>1.3.0</version>
     </parent>
 
-    <groupId>io.cloudevents</groupId>
     <artifactId>cloudevents-api</artifactId>
     <name>CloudEvents - API</name>
-    <version>1.3.0</version>
+    <version>${parent.version}</version>
     <packaging>jar</packaging>
 
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>com.fasterxml.jackson</groupId>
+                <artifactId>jackson-bom</artifactId>
+                <version>${jackson.version}</version>
+                <scope>import</scope>
+                <type>pom</type>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
     <dependencies>
+
+        <!-- Jackson -->
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-core</artifactId>
-            <version>${jackson.version}</version>
         </dependency>
-
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>${jackson.version}</version>
         </dependency>
 
+        <!-- Test deps -->
         <dependency>
-            <groupId>com.fasterxml.jackson.datatype</groupId>
-            <artifactId>jackson-datatype-jdk8</artifactId>
-            <version>${jackson.version}</version>
-        </dependency>
-
-        <dependency>
-            <groupId>org.hibernate.validator</groupId>
-            <artifactId>hibernate-validator</artifactId>
-            <version>${hibernate-validator.version}</version>
-        </dependency>
-
-        <dependency>
-             <groupId>org.glassfish</groupId>
-             <artifactId>jakarta.el</artifactId>
-             <version>${jakarta.el.version}</version>
-        </dependency>
-
-        <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>4.12</version>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>5.4.2</version>
             <scope>test</scope>
         </dependency>
 
@@ -76,10 +69,4 @@
 
     </dependencies>
 
-    <properties>
-        <jackson.version>2.10.1</jackson.version>
-        <hibernate-validator.version>6.0.17.Final</hibernate-validator.version>
-        <jakarta.el.version>3.0.3</jakarta.el.version>
-    </properties>
-
 </project>

api/src/main/java/io/cloudevents/Attributes.java

@@ -16,50 +16,48 @@
 package io.cloudevents;
 
 import java.net.URI;
+import java.time.ZonedDateTime;
 import java.util.Optional;
 
-import javax.validation.constraints.NotBlank;
-import javax.validation.constraints.NotNull;
-
-import com.fasterxml.jackson.annotation.JsonIgnore;
-
 /**
  * The marker interface for CloudEvents attributes
- *  
+ *
  * @author fabiojose
  *
  */
 public interface Attributes {
 
+    /**
+     * @return The version of the CloudEvents specification which the event uses
+     */
+    SpecVersion getSpecVersion();
+
 	/**
 	 * @return Identifies the event. Producers MUST ensure that source + id is unique for each distinct event
 	 */
-	@NotBlank
 	String getId();
 
 	/**
 	 * @return A value describing the type of event related to the originating occurrence.
 	 */
-	@NotBlank
 	String getType();
 
 	/**
 	 * @return The context in which an event happened.
 	 */
-	@NotNull
 	URI getSource();
 
 	/**
-	 * @return The version of the CloudEvents specification which the event uses
-	 */
-	@NotBlank
-	String getSpecversion();
-
-	/**
+     * TODO
 	 * A common way to get the media type of CloudEvents 'data';
 	 * @return If has a value, it MUST follows the <a href="https://tools.ietf.org/html/rfc2046">RFC2046</a>
 	 */
-	@JsonIgnore
-	Optional<String> getMediaType();
-
+	Optional<String> getDataContentType();
+
+	Optional<URI> getDataSchema();
+
+	Optional<String> getSubject();
+
+	Optional<ZonedDateTime> getTime();
+
 }

api/src/main/java/io/cloudevents/CloudEvent.java

@@ -15,31 +15,62 @@
  */
 package io.cloudevents;
 
+import com.fasterxml.jackson.databind.JsonNode;
+
 import java.util.Map;
 import java.util.Optional;
 
 /**
  * An abstract event envelope
- * @param <A> The attributes type
- * @param <T> The 'data' type
  * @author fabiojose
+ * @author slinkydeveloper
  */
-public interface CloudEvent<A extends Attributes, T> {
+public interface CloudEvent {
 
     /**
      * The event context attributes
      */
-    A getAttributes();
+    Attributes getAttributes();
 
     /**
      * The event data
      */
-    Optional<T> getData();
+    Optional<String> getDataAsString() throws DataConversionException;
 
-    byte[] getDataBase64();
+    /**
+     * The event data
+     */
+    Optional<byte[]> getDataAsBytes() throws DataConversionException;
+
+    /**
+     * The event data
+     */
+    Optional<JsonNode> getDataAsJson() throws DataConversionException;
 
     /**
      * The event extensions
+     *
+     * Extensions values could be String/Number/Boolean
      */
     Map<String, Object> getExtensions();
+
+    /**
+     * Write an extension into this cloud event
+     * @param e
+     */
+    default void writeExtension(Extension e) {
+        e.writeToEvent(this);
+    }
+
+    static io.cloudevents.v1.CloudEventBuilder build() {
+        return buildV1();
+    }
+
+    static io.cloudevents.v1.CloudEventBuilder buildV1() {
+        return new io.cloudevents.v1.CloudEventBuilder();
+    }
+
+    static io.cloudevents.v03.CloudEventBuilder buildV03() {
+        return new io.cloudevents.v03.CloudEventBuilder();
+    }
 }

api/src/main/java/io/cloudevents/DataConversionException.java

@@ -0,0 +1,8 @@
+package io.cloudevents;
+
+public class DataConversionException extends RuntimeException {
+
+    public DataConversionException(String from, String to, Throwable cause) {
+        super("Cannot convert " + from + " data to " + to, cause);
+    }
+}

api/src/main/java/io/cloudevents/Extension.java

@@ -0,0 +1,9 @@
+package io.cloudevents;
+
+public interface Extension {
+
+    void readFromEvent(CloudEvent event);
+
+    void writeToEvent(CloudEvent event);
+
+}

api/src/main/java/io/cloudevents/SpecVersion.java

@@ -0,0 +1,25 @@
+package io.cloudevents;
+
+public enum SpecVersion {
+    V03("0.3"),
+    V1("1.0");
+
+    private final String stringValue;
+
+    SpecVersion(String stringValue) {
+        this.stringValue = stringValue;
+    }
+
+    @Override
+    public String toString() {
+        return this.stringValue;
+    }
+
+    public static SpecVersion parse(String sv) {
+        switch (sv) {
+            case "0.3": return SpecVersion.V03;
+            case "1.0": return SpecVersion.V1;
+            default: throw new IllegalArgumentException("Unrecognized SpecVersion "+ sv);
+        }
+    }
+}