Add smoke tests.

Add release smoke-tests.

Closes #30

smoke-tests/src/test/java/com/example/smoketests/SmokeTestsApplicationTests.java

@@ -0,0 +1,50 @@
+package com.example.smoketests;
+
+import static org.assertj.core.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.data.cassandra.core.mapping.CassandraMappingContext;
+import org.springframework.data.elasticsearch.core.mapping.SimpleElasticsearchMappingContext;
+import org.springframework.data.jdbc.core.mapping.JdbcMappingContext;
+import org.springframework.data.jpa.domain.JpaSort;
+import org.springframework.data.mongodb.core.mapping.MongoMappingContext;
+
+/**
+ * Smoke tests to bootstrap Spring module components to verify they are functional.
+ */
+class SmokeTestsApplicationTests {
+
+	@Test
+	void cassandra() {
+
+		CassandraMappingContext context = new CassandraMappingContext();
+		assertThat(context).isNotNull();
+	}
+
+	@Test
+	void elasticsearch() {
+
+		SimpleElasticsearchMappingContext context = new SimpleElasticsearchMappingContext();
+		assertThat(context).isNotNull();
+	}
+
+	@Test
+	void mongo() {
+
+		MongoMappingContext context = new MongoMappingContext();
+		assertThat(context).isNotNull();
+	}
+
+	@Test
+	void jpa() {
+		assertThat(JpaSort.unsafe("hello")).isNotNull();
+	}
+
+	@Test
+	void jdbc() {
+		JdbcMappingContext context = new JdbcMappingContext();
+		assertThat(context).isNotNull();
+	}
+
+}