Update 6 files

- /src1/main/resources/application.yml
- /src1/main/java/com/v2d/document/config/AppProperties.java
- /src1/main/java/com/v2d/document/service/ExternalApiService.java
- /src1/main/java/com/v2d/document/controller/GenerateController.java
- /src1/test/AppPropertiesTest.java
- /README.md

src1/test/AppPropertiesTest.java

@@ -0,0 +1,20 @@
+package com.v2d.document.config;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class AppPropertiesTest {
+    private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
+            .withUserConfiguration(AppProperties.class)
+            .withPropertyValues("app.external.apiKey=TEST_KEY");
+
+    @Test
+    void bindsApiKey() {
+        contextRunner.run(context -> {
+            AppProperties props = context.getBean(AppProperties.class);
+            assertThat(props.getApiKey()).isEqualTo("TEST_KEY");
+        });
+    }
+}