[FLINK-16415] [core] Introduce JsonModuleFactory
The JsonModuleFactory is a static factory that creates JsonModules based
on the specified format version.
We currently only have one version, 1.0, and one corresponding
JsonModule, i.e. the JsonModule class. We need to further refactor
Pointers and JsonModule in the future once we introduce more versions.
diff --git a/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/FormatVersion.java b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/FormatVersion.java
new file mode 100644
index 0000000..8f01a33
--- /dev/null
+++ b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/FormatVersion.java
@@ -0,0 +1,43 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.flink.statefun.flink.core.jsonmodule;
+
+enum FormatVersion {
+ v1_0("1.0");
+
+ private String versionStr;
+
+ FormatVersion(String versionStr) {
+ this.versionStr = versionStr;
+ }
+
+ @Override
+ public String toString() {
+ return versionStr;
+ }
+
+ static FormatVersion fromString(String versionStr) {
+ switch (versionStr) {
+ case "1.0":
+ return v1_0;
+ default:
+ throw new IllegalArgumentException("Unrecognized format version: " + versionStr);
+ }
+ }
+}
diff --git a/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/JsonModuleFactory.java b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/JsonModuleFactory.java
new file mode 100644
index 0000000..3616bcd
--- /dev/null
+++ b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/JsonModuleFactory.java
@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.flink.statefun.flink.core.jsonmodule;
+
+import java.net.URL;
+import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.JsonNode;
+import org.apache.flink.statefun.flink.common.json.Selectors;
+import org.apache.flink.statefun.sdk.spi.StatefulFunctionModule;
+
+final class JsonModuleFactory {
+
+ private JsonModuleFactory() {}
+
+ static StatefulFunctionModule create(JsonNode root, URL moduleUrl) {
+ final FormatVersion formatVersion = formatVersion(root);
+ final JsonNode spec = root.at(Pointers.MODULE_SPEC);
+
+ switch (formatVersion) {
+ case v1_0:
+ return new JsonModule(spec, moduleUrl);
+ default:
+ throw new IllegalArgumentException("Unrecognized format version: " + formatVersion);
+ }
+ }
+
+ private static FormatVersion formatVersion(JsonNode root) {
+ String versionStr = Selectors.textAt(root, Pointers.FORMAT_VERSION);
+ return FormatVersion.fromString(versionStr);
+ }
+}
diff --git a/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/Pointers.java b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/Pointers.java
index cc7caec..5c5b973 100644
--- a/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/Pointers.java
+++ b/statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/jsonmodule/Pointers.java
@@ -23,6 +23,8 @@
private Pointers() {}
+ public static final JsonPointer FORMAT_VERSION = JsonPointer.compile("/version");
+
// -------------------------------------------------------------------------------------
// top level spec definition
// -------------------------------------------------------------------------------------
