[WIP] Add schema test

src/test/java/io/streamnative/connectors/kafka/schema/SchemaTest.java

@@ -0,0 +1,169 @@
+/**
+ * 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 io.streamnative.connectors.kafka.schema;
+
+import java.io.ByteArrayOutputStream;
+import org.apache.avro.Schema;
+import org.apache.avro.generic.GenericDatumWriter;
+import org.apache.avro.generic.GenericRecord;
+import org.apache.avro.generic.GenericRecordBuilder;
+import org.apache.avro.io.BinaryEncoder;
+import org.apache.avro.io.EncoderFactory;
+import org.apache.pulsar.shade.org.apache.avro.generic.GenericDatumReader;
+import org.apache.pulsar.shade.org.apache.avro.io.Decoder;
+import org.apache.pulsar.shade.org.apache.avro.io.DecoderFactory;
+import org.junit.Test;
+
+/**
+ * Schema
+ */
+public class SchemaTest {
+
+    private static final String PULSAR_SCHEMA_1 = "{\n" +
+        "    \"type\": \"record\",\n" +
+        "    \"name\": \"User\",\n" +
+        "    \"namespace\": \"io.streamnative.connectors.kafka.example\",\n" +
+        "    \"fields\": [\n" +
+        "      {\n" +
+        "        \"name\": \"name\",\n" +
+        "        \"type\": [\n" +
+        "          \"string\",\n" +
+        "          \"null\"\n" +
+        "        ]\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"name\": \"age\",\n" +
+        "        \"type\": [\n" +
+        "          \"string\",\n" +
+        "          \"null\"\n" +
+        "        ]\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"name\": \"gpa\",\n" +
+        "        \"type\": [\n" +
+        "          \"string\",\n" +
+        "          \"null\"\n" +
+        "        ]\n" +
+        "      }\n" +
+        "    ]\n" +
+        "  }";
+
+    private static final String PULSAR_SCHEMA_2 = "{\n" +
+        "    \"type\": \"record\",\n" +
+        "    \"name\": \"User\",\n" +
+        "    \"namespace\": \"io.streamnative.connectors.kafka.example\",\n" +
+        "    \"fields\": [\n" +
+        "      {\n" +
+        "        \"name\": \"name\",\n" +
+        "        \"type\": [\n" +
+        "          \"null\",\n" +
+        "          \"string\"\n" +
+        "        ]\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"name\": \"age\",\n" +
+        "        \"type\": [\n" +
+        "          \"null\",\n" +
+        "          \"string\"\n" +
+        "        ]\n" +
+        "      },\n" +
+        "      {\n" +
+        "        \"name\": \"gpa\",\n" +
+        "        \"type\": [\n" +
+        "          \"null\",\n" +
+        "          \"string\"\n" +
+        "        ]\n" +
+        "      }\n" +
+        "    ]\n" +
+        "  }";
+
+    private static final String PRESTO_SCHEMA = "{\"type\":\"record\",\"name\":\"User\",\"namespace\":\"io.streamnative.connectors.kafka.example\",\"fields\":[{\"name\":\"name\",\"type\":[\"null\",\"string\"],\"default\":null},{\"name\":\"age\",\"type\":[\"null\",\"string\"],\"default\":null},{\"name\":\"gpa\",\"type\":[\"null\",\"string\"],\"default\":null}]}";
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void testSchemaWriteRead() throws Exception {
+        Schema pulsarSchema1 = new Schema.Parser().parse(PULSAR_SCHEMA_1);
+        Schema pulsarSchema2 = new Schema.Parser().parse(PULSAR_SCHEMA_2);
+        org.apache.pulsar.shade.org.apache.avro.Schema prestoSchema1 =
+            new org.apache.pulsar.shade.org.apache.avro.Schema.Parser().parse(PULSAR_SCHEMA_1);
+        org.apache.pulsar.shade.org.apache.avro.Schema prestoSchema2 =
+            new org.apache.pulsar.shade.org.apache.avro.Schema.Parser().parse(PRESTO_SCHEMA);
+
+        System.out.println("Pulsar schema 1 : " + pulsarSchema1.toString());
+        System.out.println("Pulsar schema 2 : " + pulsarSchema2.toString());
+        System.out.println("Presto schema 1 : " + prestoSchema1.toString());
+        System.out.println("Presto schema 2 : " + prestoSchema2.toString());
+
+        BinaryEncoder encoder = null;
+        GenericDatumWriter<GenericRecord> writer1 = new GenericDatumWriter<>(pulsarSchema1);
+        ByteArrayOutputStream byteArrayOutputStream1 = new ByteArrayOutputStream();
+        encoder = EncoderFactory.get().binaryEncoder(byteArrayOutputStream1, encoder);
+
+        GenericRecord record = new GenericRecordBuilder(pulsarSchema1)
+            .set("name", "test")
+            .set("age", "1000")
+            .set("gpa", "1")
+            .build();
+
+        writer1.write(record, encoder);
+        encoder.flush();
+        byte[] data1 = byteArrayOutputStream1.toByteArray();
+
+        GenericDatumWriter<GenericRecord> writer2 = new GenericDatumWriter<>(pulsarSchema1);
+        ByteArrayOutputStream byteArrayOutputStream2 = new ByteArrayOutputStream();
+        encoder = EncoderFactory.get().binaryEncoder(byteArrayOutputStream2, encoder);
+        writer2.write(record, encoder);
+        encoder.flush();
+        byte[] data2 = byteArrayOutputStream2.toByteArray();
+
+        // read
+        System.out.println("Using presto schema v2 to decode v1 data failed");
+        GenericDatumReader reader1 = new GenericDatumReader<>(prestoSchema2);
+        Decoder decoder = DecoderFactory.get().binaryDecoder(data1, null);
+        try {
+            org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord prestoRecord =
+                (org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord) reader1.read(null, decoder);
+        } catch (ArrayIndexOutOfBoundsException e) {
+            // expected
+            e.printStackTrace();
+        }
+
+        System.out.println("Using presto v1 and v2 schema to decode v1 data should succeed : ");
+        GenericDatumReader reader2 = new GenericDatumReader<>(prestoSchema1, prestoSchema2);
+        decoder = DecoderFactory.get().binaryDecoder(data1, null);
+        org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord prestoRecord =
+            (org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord) reader2.read(null, decoder);
+
+        System.out.println("Name:\t" + prestoRecord.get("name"));
+        System.out.println("Age:\t" + prestoRecord.get("age"));
+        System.out.println("Gpa:\t" + prestoRecord.get("gpa"));
+
+        // read
+        System.out.println("Using presto schema v1 to decode v2 data succeed");
+        GenericDatumReader reader3 = new GenericDatumReader<>(prestoSchema1);
+        decoder = DecoderFactory.get().binaryDecoder(data2, null);
+        org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord prestoRecord3 =
+            (org.apache.pulsar.shade.org.apache.avro.generic.GenericRecord) reader3.read(null, decoder);
+
+        System.out.println("Name:\t" + prestoRecord3.get("name"));
+        System.out.println("Age:\t" + prestoRecord3.get("age"));
+        System.out.println("Gpa:\t" + prestoRecord3.get("gpa"));
+    }
+
+}