From c1af31f41dee7872eab009bdd739ad5dc819477b Mon Sep 17 00:00:00 2001
From: maciejrusek <git@mrusek.pl>
Date: Tue, 21 Apr 2026 21:48:49 +0200
Subject: [PATCH] Added database connection, added test and start with
 Testcontainers.

---
 .env.example                               |  3 ++
 .gitignore                                 |  3 +-
 README.md                                  |  4 +--
 docker-compose.yaml                        | 18 ++++++++++
 pom.xml                                    | 40 ++++++++++++++++++++++
 src/main/java/util/DatabaseConnection.java | 33 ++++++++++++++++++
 src/test/java/DatabaseConnectionTest.java  | 37 ++++++++++++++++++++
 7 files changed, 135 insertions(+), 3 deletions(-)
 create mode 100644 .env.example
 create mode 100644 docker-compose.yaml
 create mode 100644 src/main/java/util/DatabaseConnection.java
 create mode 100644 src/test/java/DatabaseConnectionTest.java

diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..f732a35
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,3 @@
+POSTGRES_PASSWORD=""
+POSTGRES_USER=""
+POSTGRES_DB=""
diff --git a/.gitignore b/.gitignore
index 480bdf5..4235d41 100644
--- a/.gitignore
+++ b/.gitignore
@@ -36,4 +36,5 @@ build/
 .vscode/
 
 ### Mac OS ###
-.DS_Store
\ No newline at end of file
+.DS_Store
+.env
\ No newline at end of file
diff --git a/README.md b/README.md
index b69166d..00c31fd 100644
--- a/README.md
+++ b/README.md
@@ -15,5 +15,5 @@
 
 
 ## TODO:
-- [ ] Fabryka połączenia do bazy danych
-- [ ] Testy bazy
\ No newline at end of file
+- [x] Fabryka połączenia do bazy danych
+- [x] Testy bazy
\ No newline at end of file
diff --git a/docker-compose.yaml b/docker-compose.yaml
new file mode 100644
index 0000000..2925206
--- /dev/null
+++ b/docker-compose.yaml
@@ -0,0 +1,18 @@
+services:
+
+  db:
+    image: postgres:18.3
+    restart: always
+    shm_size: 128mb
+    environment:
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+      POSTGRES_USER: ${POSTGRES_USER}
+      POSTGRES_DB: ${POSTGRES_DB}
+    ports:
+      - 12900:5432
+
+  adminer:
+    image: adminer
+    restart: always
+    ports:
+      - 12901:8080
diff --git a/pom.xml b/pom.xml
index c8e50cc..b38bf60 100644
--- a/pom.xml
+++ b/pom.xml
@@ -14,4 +14,44 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
+    <dependencies>
+        <dependency>
+            <groupId>com.zaxxer</groupId>
+            <artifactId>HikariCP</artifactId>
+            <version>7.0.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>42.7.10</version>
+        </dependency>
+
+        <dependency>
+            <groupId>io.github.cdimascio</groupId>
+            <artifactId>dotenv-java</artifactId>
+            <version>3.2.0</version>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>1.19.8</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>5.9.3</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
 </project>
\ No newline at end of file
diff --git a/src/main/java/util/DatabaseConnection.java b/src/main/java/util/DatabaseConnection.java
new file mode 100644
index 0000000..7676037
--- /dev/null
+++ b/src/main/java/util/DatabaseConnection.java
@@ -0,0 +1,33 @@
+package util;
+
+import com.zaxxer.hikari.HikariConfig;
+import com.zaxxer.hikari.HikariDataSource;
+import io.github.cdimascio.dotenv.Dotenv;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public class DatabaseConnection {
+
+    private static Dotenv dotenv = Dotenv.load();
+
+    private static HikariConfig config = new HikariConfig();
+    private static HikariDataSource ds;
+
+    static {
+        config.setJdbcUrl(dotenv.get("JDBC"));
+        config.setUsername(dotenv.get("POSTGRES_USER"));
+        config.setPassword(dotenv.get("POSTGRES_PASSWORD"));
+        config.setDriverClassName("org.postgresql.Driver");
+        config.setMaximumPoolSize(10);
+        config.setMinimumIdle(2);
+        ds = new HikariDataSource(config);
+    }
+
+    private DatabaseConnection() {};
+
+    public static Connection getConnection() throws SQLException {
+        return ds.getConnection();
+    }
+
+}
diff --git a/src/test/java/DatabaseConnectionTest.java b/src/test/java/DatabaseConnectionTest.java
new file mode 100644
index 0000000..87a7661
--- /dev/null
+++ b/src/test/java/DatabaseConnectionTest.java
@@ -0,0 +1,37 @@
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.Test;
+import static org.junit.Assert.assertFalse;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+
+import org.testcontainers.containers.PostgreSQLContainer;
+
+public class DatabaseConnectionTest {
+
+    static PostgreSQLContainer<?> postgres = new PostgreSQLContainer<>(
+            "postgres:16-alpine"
+    );
+
+    @BeforeAll
+    static void beforeAll() {
+        postgres.start();
+    }
+
+    @AfterAll
+    static void afterAll() {
+        postgres.stop();
+    }
+
+    @Test
+    public void shouldConnect() throws Exception {
+        try (Connection conn = DriverManager.getConnection(
+                postgres.getJdbcUrl(),
+                postgres.getUsername(),
+                postgres.getPassword()
+        )) {
+            assertFalse(conn.isClosed());
+        }
+    }
+}