Testcontainers for Java: Add examples for init scripts and function

testing/testcontainers/java/README.rst

@@ -42,6 +42,8 @@ of examples you can explore here:
   Testcontainer instance honoring the ``CRATEDB_VERSION`` environment variable, suitable
   for running a test matrix on different versions of CrateDB, shared across multiple test
   classes.
+- ``TestSqlInitialization``: Demonstrate different ways how Testcontainers can run an init script after
+  the database container is started, but before your code is given a connection to it.
 
 [1]: Sometimes, it might be useful to define a container that is only started once for
 several test classes. There is no special support for this use case provided by
@@ -64,6 +66,9 @@ Usage
     # Run individual tests.
     ./gradlew test --tests TestFunctionScope
 
+    # Inspect tracebacks on failures.
+    ./gradlew test --tests TestFunctionScope --info
+
     # Run test case showing how to select CrateDB version per environment variable.
     export CRATEDB_VERSION=5.2.3
     export CRATEDB_VERSION=nightly

testing/testcontainers/java/src/main/java/io/crate/example/testing/Application.java

@@ -74,6 +74,10 @@ public Results querySummitsTable() throws IOException, SQLException {
         return this.query("SELECT * FROM sys.summits ORDER BY height DESC LIMIT 3");
     }
 
+    public Results showCreateTable(String tablename) throws IOException, SQLException {
+        return this.query("SHOW CREATE TABLE " + tablename);
+    }
+
     public Results query(String sql) throws IOException, SQLException {
         Properties connectionProps = new Properties();
         connectionProps.put("user", user);

testing/testcontainers/java/src/main/resources/init.sql

@@ -0,0 +1,15 @@
+CREATE TABLE alltypes (
+    name STRING PRIMARY KEY,
+    date TIMESTAMP,
+    datetime_tz TIMESTAMP WITH TIME ZONE,
+    datetime_notz TIMESTAMP WITHOUT TIME ZONE,
+    nullable_datetime TIMESTAMP,
+    nullable_date TIMESTAMP,
+    kind STRING,
+    flag BOOLEAN,
+    position INTEGER,
+    description STRING,
+    details ARRAY(OBJECT),
+    attributes OBJECT(DYNAMIC),
+    coordinates GEO_POINT
+) WITH (number_of_replicas=0);

testing/testcontainers/java/src/test/java/io/crate/example/testing/TestSqlInitialization.java

@@ -0,0 +1,68 @@
+package io.crate.example.testing;
+
+import org.junit.Test;
+
+import java.io.IOException;
+import java.sql.SQLException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+
+/**
+ * Database containers launched with SQL initialization/provisioning script/routine.
+ * <p>
+ *   <a href="https://www.testcontainers.org/modules/databases/jdbc/#database-containers-launched-via-jdbc-url-scheme"/>
+ *   <a href="https://www.testcontainers.org/features/reuse/"/>
+ * </p>
+ */
+public class TestSqlInitialization {
+
+    /**
+     * Launch container with CrateDB 5.2, using `TC_INITSCRIPT` to address a file in Java's CLASSPATH.
+     * <a href="https://www.testcontainers.org/modules/databases/jdbc/#using-a-classpath-init-script"/>
+     */
+    @Test
+    public void testTcInitClasspathFile() throws SQLException, IOException {
+        String connectionUrl = "jdbc:tc:cratedb:5.2://localhost/doc?user=crate&TC_REUSABLE=true&TC_INITSCRIPT=init.sql";
+        System.out.printf("Connecting to %s%n", connectionUrl);
+
+        // Invoke `SHOW CREATE TABLE ...` query.
+        Application app = new Application(connectionUrl);
+        var results= app.showCreateTable("alltypes");
+        assertThat(results.metaData().getColumnCount()).isEqualTo(1);
+        assertThat(results.rows()).hasSize(1);
+    }
+
+    /**
+     * Launch container with CrateDB 5.2, using `TC_INITSCRIPT` to address an arbitrary file on the filesystem.
+     * <a href="https://www.testcontainers.org/modules/databases/jdbc/#using-an-init-script-from-a-file"/>
+     */
+    @Test
+    public void testTcInitArbitraryFile() throws SQLException, IOException {
+        String connectionUrl = "jdbc:tc:cratedb:5.2://localhost/doc?user=crate&TC_REUSABLE=true&TC_INITSCRIPT=file:src/main/resources/init.sql";
+        System.out.printf("Connecting to %s%n", connectionUrl);
+
+        // Invoke `SHOW CREATE TABLE ...` query.
+        Application app = new Application(connectionUrl);
+        var results= app.showCreateTable("alltypes");
+        assertThat(results.metaData().getColumnCount()).isEqualTo(1);
+        assertThat(results.rows()).hasSize(1);
+    }
+
+    /**
+     * Launch container with CrateDB 5.2, using an init function.
+     * <a href="https://www.testcontainers.org/modules/databases/jdbc/#using-an-init-script-from-a-file"/>
+     */
+    @Test
+    public void testTcInitFunction() throws SQLException, IOException {
+        String connectionUrl = "jdbc:tc:cratedb:5.2://localhost/doc?user=crate&TC_INITFUNCTION=io.crate.example.testing.utils.TestingHelpers::sqlInitFunction";
+        System.out.printf("Connecting to %s%n", connectionUrl);
+
+        // Invoke `SHOW CREATE TABLE ...` query.
+        Application app = new Application(connectionUrl);
+        var results= app.showCreateTable("foobar_init");
+        assertThat(results.metaData().getColumnCount()).isEqualTo(1);
+        assertThat(results.rows()).hasSize(1);
+    }
+
+}

testing/testcontainers/java/src/test/java/io/crate/example/testing/utils/TestingHelpers.java

@@ -3,7 +3,10 @@
 import io.crate.example.testing.Application;
 import org.testcontainers.utility.DockerImageName;
 
+import java.io.IOException;
+import java.sql.Connection;
 import java.sql.SQLException;
+import java.sql.Statement;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -36,4 +39,21 @@ public static void assertResults(Application.Results results) throws SQLExceptio
                 "Monte Rosa",
                 "Dom");
     }
+
+    /**
+     * Support function for initializing CrateDB with SQL using an init function.
+     * You can run a simple schema setup or Flyway/liquibase DB migrations here, at your disposal.
+     * <a href="https://www.testcontainers.org/modules/databases/jdbc/#using-an-init-function"/>
+     */
+    public static void sqlInitFunction(Connection connection) throws SQLException, IOException, InterruptedException {
+        try (Statement stmt = connection.createStatement()) {
+            boolean checkResults = stmt.execute("CREATE TABLE IF NOT EXISTS foobar_init (id INTEGER)");
+            if (checkResults) {
+                System.out.println("Success.");
+            } else {
+                throw new SQLException("ERROR: SQL initialization failed");
+            }
+        }
+    }
+
 }