Started R2DBC PostgreSQL example

ankane · ankane · commit 63ed919cb703 · 2023-12-12T13:23:57.000-05:00
diff --git a/README.md b/README.md
@@ -28,7 +28,7 @@ For other build tools, see [this page](https://central.sonatype.com/artifact/com
 
 And follow the instructions for your database library:
 
-- Java - [JDBC](#jdbc-java), [Spring JDBC](#spring-jdbc), [Hibernate](#hibernate)
+- Java - [JDBC](#jdbc-java), [Spring JDBC](#spring-jdbc), [Hibernate](#hibernate), [R2DBC](#r2dbc)
 - Kotlin - [JDBC](#jdbc-kotlin)
 - Groovy - [JDBC](#jdbc-groovy), [Groovy SQL](#groovy-sql)
 - Scala - [JDBC](#jdbc-scala), [Slick](#slick)
@@ -204,6 +204,20 @@ List<Item> items = entityManager
 
 See a [full example](src/test/java/com/pgvector/HibernateTest.java)
 
+## R2DBC
+
+R2DBC PostgreSQL 1.0.3+ supports the [vector type](https://github.com/pgjdbc/r2dbc-postgresql#data-type-mapping) (use this instead of `com.pgvector.pgvector`).
+
+For Maven, add to `pom.xml` under `<dependencies>`:
+
+```xml
+<dependency>
+    <groupId>org.postgresql</groupId>
+    <artifactId>r2dbc-postgresql</artifactId>
+    <version>1.0.3.RELEASE</version>
+</dependency>
+```
+
 ## JDBC (Kotlin)
 
 Import the `PGvector` class
diff --git a/pom.xml b/pom.xml
@@ -101,6 +101,11 @@
             <version>6.4.0.Final</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>r2dbc-postgresql</artifactId>
+            <version>1.0.3.RELEASE</version>
+        </dependency>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
diff --git a/src/test/java/com/pgvector/R2DBCTest.java b/src/test/java/com/pgvector/R2DBCTest.java
@@ -0,0 +1,35 @@
+package com.pgvector;
+
+import java.sql.SQLException;
+import io.r2dbc.postgresql.codec.Vector;
+import io.r2dbc.spi.ConnectionFactories;
+import io.r2dbc.spi.ConnectionFactory;
+import io.r2dbc.spi.ConnectionFactoryOptions;
+import io.r2dbc.spi.Statement;
+import org.junit.jupiter.api.Test;
+import reactor.core.publisher.Mono;
+
+public class R2DBCTest {
+    @Test
+    void example() throws SQLException {
+        ConnectionFactory connectionFactory = ConnectionFactories.get(
+            ConnectionFactoryOptions.builder()
+                .option(ConnectionFactoryOptions.DRIVER, "postgresql")
+                .option(ConnectionFactoryOptions.HOST, "localhost")
+                .option(ConnectionFactoryOptions.USER, System.getenv("USER"))
+                .option(ConnectionFactoryOptions.PASSWORD, "")
+                .option(ConnectionFactoryOptions.DATABASE, "pgvector_java_test")
+                .build()
+        );
+
+        Mono.from(connectionFactory.create())
+            .flatMapMany(connection -> connection
+                .createStatement("SELECT $1 AS embedding")
+                .bind("$1", Vector.of(1, 2, 3))
+                .execute())
+            .flatMap(result -> result
+                .map((row, rowMetadata) -> row.get("embedding", Vector.class)))
+            .doOnNext(System.out::println)
+            .blockLast();
+    }
+}
