convert to java

Author: zeitlinger

javaagent-tooling/src/test/groovy/io/opentelemetry/javaagent/tooling/config/ConfigurationFileTest.groovy

@@ -0,0 +1,104 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.javaagent.tooling.config;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Rule;
+import org.junit.contrib.java.lang.system.EnvironmentVariables;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.Properties;
+
+class ConfigurationFileTest {
+
+  @TempDir
+  File tmpDir;
+
+  @Rule
+  public final EnvironmentVariables environmentVariables = new EnvironmentVariables();
+
+  private String originalSystemProperty;
+  private String originalEnvironmentVariable;
+
+  @BeforeEach
+  void setUp() {
+    originalSystemProperty = System.getProperty("otel.javaagent.configuration-file");
+    originalEnvironmentVariable = System.getenv("OTEL_JAVAAGENT_CONFIGURATION_FILE");
+    System.clearProperty("otel.javaagent.configuration-file");
+  }
+
+  @AfterEach
+  void tearDown() {
+    if (originalSystemProperty != null) {
+      System.setProperty("otel.javaagent.configuration-file", originalSystemProperty);
+    } else {
+      System.clearProperty("otel.javaagent.configuration-file");
+    }
+  }
+
+  @Test
+  void shouldUseEnvVar() throws IOException {
+    String path = createFile("config", "property1=val-env");
+    environmentVariables.set("OTEL_JAVAAGENT_CONFIGURATION_FILE", path)
+
+    Properties properties = ConfigurationFile.loadConfigFile();
+
+    assertThat(properties.get("property1")).isEqualTo("val-env");
+  }
+
+  @Test
+  void shouldUseSystemProperty() throws IOException {
+    String path = createFile("config", "property1=val-sys");
+    System.setProperty("otel.javaagent.configuration-file", path);
+
+    Properties properties = ConfigurationFile.loadConfigFile();
+
+    assertThat(properties.get("property1")).isEqualTo("val-sys");
+  }
+
+  @Test
+  void shouldUseSystemPropertyOverEnvVar() throws IOException {
+    def pathEnv = createFile("configEnv", "property1=val-env")
+    String path = createFile("config", "property1=val-sys");
+    System.setProperty("otel.javaagent.configuration-file", path);
+    environmentVariables.set("OTEL_JAVAAGENT_CONFIGURATION_FILE", pathEnv)
+
+    Properties properties = ConfigurationFile.loadConfigFile();
+
+    assertThat(properties.get("property1")).isEqualTo("val-sys");
+  }
+
+  @Test
+  void shouldReturnEmptyPropertiesIfFileDoesNotExist() {
+    System.setProperty("otel.javaagent.configuration-file", "somePath");
+
+    Properties properties = ConfigurationFile.loadConfigFile();
+
+    assertThat(properties).isEmpty();
+  }
+
+  @Test
+  void shouldReturnEmptyPropertiesIfPropertyIsNotSet() {
+    Properties properties = ConfigurationFile.loadConfigFile();
+
+    assertThat(properties).isEmpty();
+  }
+
+  private String createFile(String name, String contents) throws IOException {
+    File file = new File(tmpDir, name);
+    try (FileWriter writer = new FileWriter(file)) {
+      writer.write(contents);
+    }
+    return file.getAbsolutePath();
+  }
+}