Add default database name to MongoDB Atlas

modules/mongodb/src/main/java/org/testcontainers/mongodb/MongoDBAtlasLocalContainer.java

@@ -17,6 +17,10 @@ public class MongoDBAtlasLocalContainer extends GenericContainer<MongoDBAtlasLoc
 
     private static final int MONGODB_INTERNAL_PORT = 27017;
 
+    private static final String MONGODB_DATABASE_NAME_DEFAULT = "test";
+
+    private static final String DIRECT_CONNECTION = "directConnection=true";
+
     public MongoDBAtlasLocalContainer(final String dockerImageName) {
         this(DockerImageName.parse(dockerImageName));
     }
@@ -33,6 +37,32 @@ public MongoDBAtlasLocalContainer(final DockerImageName dockerImageName) {
      * Get the connection string to MongoDB.
      */
     public String getConnectionString() {
-        return String.format("mongodb://%s:%d/?directConnection=true", getHost(), getMappedPort(MONGODB_INTERNAL_PORT));
+        return baseConnectionString() + "/?" + DIRECT_CONNECTION;
+    }
+
+    private String baseConnectionString() {
+        return String.format("mongodb://%s:%d", getHost(), getMappedPort(MONGODB_INTERNAL_PORT));
+    }
+
+    /**
+     * Gets a database specific connection string for the default {@value #MONGODB_DATABASE_NAME_DEFAULT} database.
+     *
+     * @return a database specific connection string.
+     */
+    public String getDatabaseConnectionString() {
+        return getDatabaseConnectionString(MONGODB_DATABASE_NAME_DEFAULT);
+    }
+
+    /**
+     * Gets a database specific connection string for a provided <code>databaseName</code>.
+     *
+     * @param databaseName a database name.
+     * @return a database specific connection string.
+     */
+    public String getDatabaseConnectionString(final String databaseName) {
+        if (!isRunning()) {
+            throw new IllegalStateException("MongoDBContainer should be started first");
+        }
+        return baseConnectionString() + "/" + databaseName + "?" + DIRECT_CONNECTION;
     }
 }

modules/mongodb/src/test/java/org/testcontainers/mongodb/MongoDBAtlasLocalContainerTest.java

@@ -36,6 +36,26 @@ public void getConnectionString() {
         }
     }
 
+    @Test
+    public void getDatabaseConnectionString() {
+        try (
+            MongoDBAtlasLocalContainer container = new MongoDBAtlasLocalContainer("mongodb/mongodb-atlas-local:7.0.9")
+        ) {
+            container.start();
+            String databaseConnectionString = container.getDatabaseConnectionString();
+            assertThat(databaseConnectionString).isNotNull();
+            assertThat(databaseConnectionString).startsWith("mongodb://");
+            assertThat(databaseConnectionString)
+                .isEqualTo(
+                    String.format(
+                        "mongodb://%s:%d/test?directConnection=true",
+                        container.getHost(),
+                        container.getFirstMappedPort()
+                    )
+                );
+        }
+    }
+
     @Test
     public void createAtlasIndexAndSearchIt() throws Exception {
         try (