feat: include agent info into polling (#29)

* feat: include agent info into polling

* feat: log based on custom header

* refactor: delete unnecessary code

* fix: remove StartNotifierTest.java since the according class was deleted

* fix: attempt to stabilize the IdentityManagerTest

* fix: Fix IdentityManagerTest and add salt to hashing algorithm

* fix: refactoring according review comments

---------

Co-authored-by: Benjamin Clauss <[email protected]>

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/InspectitAgentExtension.java

@@ -71,7 +71,6 @@ public AgentBuilder extend(AgentBuilder agentBuilder, ConfigProperties config) {
 
     // Notify configuration server about this agent
     NotificationManager notificationManager = NotificationManager.create();
-    notificationManager.sendStartNotification();
     // Set up shutdown notification to configuration server
     notificationManager.setUpShutdownNotification();
 

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/configuration/http/HttpConfigurationCallback.java

@@ -16,12 +16,10 @@ public class HttpConfigurationCallback implements FutureCallback<SimpleHttpRespo
 
   @Override
   public void completed(SimpleHttpResponse result) {
-    log.info(
-        "Fetched configuration from configuration server and received status code {}",
-        result.getCode());
 
+    logStatus(result);
     // Publish Event
-    if (result.getCode() == 200) {
+    if (result.getCode() == 200 || result.getCode() == 201) {
       String body = result.getBodyText();
 
       try {
@@ -45,4 +43,21 @@ public void failed(Exception ex) {
   public void cancelled() {
     log.info("Cancelled configuration fetch");
   }
+
+  private void logStatus(SimpleHttpResponse response) {
+    int statusCode = response.getCode();
+
+    if (statusCode == 200) {
+      log.info("Configuration fetched successfully");
+    } else if (statusCode == 201) {
+      log.info(
+          "Connection to configuration server was successfully established. Configuration fetched successfully");
+    } else if (statusCode == 404) {
+      log.error("Configuration not found on configuration server");
+    } else {
+      log.error(
+          "Unexpected status code: {}. Please check the configuration server connection.",
+          statusCode);
+    }
+  }
 }

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/configuration/http/HttpConfigurationFactory.java

@@ -3,16 +3,27 @@
 
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Map;
 import org.apache.hc.client5.http.async.methods.SimpleHttpRequest;
 import org.apache.hc.client5.http.async.methods.SimpleRequestBuilder;
 import org.apache.hc.core5.net.URIBuilder;
+import rocks.inspectit.gepard.agent.internal.identity.model.AgentInfo;
+import rocks.inspectit.gepard.commons.model.agent.Agent;
 
 /**
  * This factory should create different HTTP requests for the configuration server to fetch
  * inspectit configurations.
  */
 public class HttpConfigurationFactory {
 
+  public static final String X_GEPARD_SERVICE_NAME = "x-gepard-service-name";
+  public static final String X_GEPARD_VM_ID = "x-gepard-vm-id";
+  public static final String X_GEPARD_GEPARD_VERSION = "x-gepard-gepard-version";
+  public static final String X_GEPARD_OTEL_VERSION = "x-gepard-otel-version";
+  public static final String X_GEPARD_JAVA_VERSION = "x-gepard-java-version";
+  public static final String X_GEPARD_START_TIME = "x-gepard-start-time";
+  public static final String X_GEPARD_ATTRIBUTE = "x-gepard-attribute-";
+
   private HttpConfigurationFactory() {}
 
   /**
@@ -23,8 +34,32 @@ private HttpConfigurationFactory() {}
    */
   public static SimpleHttpRequest createConfigurationRequest(String baseUrl)
       throws URISyntaxException {
-    URI uri = new URIBuilder(baseUrl + "/agent-configuration").build();
 
-    return SimpleRequestBuilder.get(uri).build();
+    AgentInfo agentInfo = AgentInfo.INFO;
+
+    URI uri = new URIBuilder(baseUrl + "/agent-configuration/" + agentInfo.getAgentId()).build();
+
+    SimpleRequestBuilder requestBuilder = SimpleRequestBuilder.get(uri);
+
+    return buildRequestWithHeaders(requestBuilder, agentInfo.getAgent()).build();
+  }
+
+  private static SimpleRequestBuilder buildRequestWithHeaders(
+      SimpleRequestBuilder requestBuilder, Agent agent) {
+    Map<String, String> headers =
+        Map.of(
+            X_GEPARD_SERVICE_NAME, agent.getServiceName(),
+            X_GEPARD_VM_ID, agent.getVmId(),
+            X_GEPARD_GEPARD_VERSION, agent.getGepardVersion(),
+            X_GEPARD_OTEL_VERSION, agent.getOtelVersion(),
+            X_GEPARD_JAVA_VERSION, agent.getJavaVersion(),
+            X_GEPARD_START_TIME, agent.getStartTime().toString());
+
+    headers.forEach(requestBuilder::addHeader);
+    agent
+        .getAttributes()
+        .forEach((key, value) -> requestBuilder.addHeader(X_GEPARD_ATTRIBUTE + key, value));
+
+    return requestBuilder;
   }
 }

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/internal/identity/IdentityManager.java

@@ -6,6 +6,8 @@
 import java.nio.charset.StandardCharsets;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.util.Base64;
 import java.util.Objects;
 import rocks.inspectit.gepard.agent.internal.identity.model.IdentityInfo;
 
@@ -38,13 +40,16 @@ public IdentityInfo getIdentityInfo() {
    * @return the SHA3-256 hashed <code>String</code>
    */
   private static String hash(String input) {
+    String salt = generateSalt();
+    String saltedInput = salt + input;
+
     MessageDigest messageDigest;
     try {
       messageDigest = MessageDigest.getInstance("SHA3-256");
     } catch (NoSuchAlgorithmException e) {
       throw new UnsupportedOperationException("SHA3-256 not supported", e);
     }
-    byte[] bytes = messageDigest.digest(input.getBytes(StandardCharsets.UTF_8));
+    byte[] bytes = messageDigest.digest(saltedInput.getBytes(StandardCharsets.UTF_8));
     StringBuilder hexString = new StringBuilder(2 * bytes.length);
     for (byte b : bytes) {
       String hex = Integer.toHexString(0xff & b);
@@ -55,4 +60,12 @@ private static String hash(String input) {
     }
     return hexString.toString();
   }
+
+  /** Generates a secure random 128bit string/salt */
+  private static String generateSalt() {
+    byte[] salt = new byte[16];
+    SecureRandom secureRandom = new SecureRandom();
+    secureRandom.nextBytes(salt);
+    return Base64.getEncoder().encodeToString(salt);
+  }
 }

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/notification/NotificationManager.java

@@ -15,13 +15,10 @@ public class NotificationManager {
 
   private final String serverBaseUrl;
 
-  private final StartNotifier startNotifier;
-
   private final ShutdownNotifier shutdownNotifier;
 
   private NotificationManager(String serverBaseUrl) {
     this.serverBaseUrl = serverBaseUrl;
-    this.startNotifier = new StartNotifier();
     this.shutdownNotifier = new ShutdownNotifier();
   }
 
@@ -35,22 +32,6 @@ public static NotificationManager create() {
     return new NotificationManager(url);
   }
 
-  /**
-   * Sends a message to the configuration server, to notify it about this agent starting, if a
-   * configuration server url was provided.
-   *
-   * @return true, if the notification was executed successfully
-   */
-  public boolean sendStartNotification() {
-    boolean successful = false;
-    if (serverBaseUrl.isEmpty()) log.info("No configuration server url was provided");
-    else {
-      log.info("Sending start notification to configuration server with url: {}", serverBaseUrl);
-      successful = startNotifier.sendNotification(serverBaseUrl);
-    }
-    return successful;
-  }
-
   /**
    * Sets up a shutdown notification to the configuration server, if a configuration server url was
    * provided.

inspectit-gepard-agent/src/main/java/rocks/inspectit/gepard/agent/notification/http/NotificationFactory.java

@@ -24,27 +24,6 @@ public class NotificationFactory {
 
   private NotificationFactory() {}
 
-  /**
-   * Create an HTTP post request to notify the configuration server about the starting agent and
-   * it's information.
-   *
-   * @param baseUrl the base url of the configuration server
-   * @return the HTTP post request, containing agent information
-   * @throws URISyntaxException invalid uri
-   * @throws JsonProcessingException corrupted agent information
-   */
-  public static SimpleHttpRequest createStartNotification(String baseUrl)
-      throws URISyntaxException, JsonProcessingException {
-    String agentId = AgentInfo.INFO.getAgentId();
-    URI uri = new URI(baseUrl + "/connections/" + agentId);
-    String agentInfoString = mapper.writeValueAsString(AgentInfo.INFO.getAgent());
-
-    return SimpleRequestBuilder.post(uri)
-        .setBody(agentInfoString, ContentType.APPLICATION_JSON)
-        .setHeader("content-type", "application/json")
-        .build();
-  }
-
   /**
    * Create an HTTP put request to notify the configuration server about the shutting down agent.
    *

inspectit-gepard-agent/src/test/java/rocks/inspectit/gepard/agent/configuration/http/HttpConfigurationPollerTest.java

@@ -12,13 +12,16 @@
 import org.mockserver.model.HttpError;
 import rocks.inspectit.gepard.agent.MockServerTestBase;
 import rocks.inspectit.gepard.agent.configuration.persistence.ConfigurationPersistence;
+import rocks.inspectit.gepard.agent.internal.identity.model.AgentInfo;
 
 class HttpConfigurationPollerTest extends MockServerTestBase {
 
   private static HttpConfigurationPoller poller;
 
   private static ConfigurationPersistence persistence;
 
+  private static String AGENT_ID = AgentInfo.INFO.getAgentId();
+
   @BeforeEach
   void beforeEach() {
     persistence = mock(ConfigurationPersistence.class);
@@ -33,7 +36,7 @@ void afterEach() {
   @Test
   void runDoesntLoadLocalConfigurationWhenPollingIsSuccessful() {
     mockServer
-        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration"))
+        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration/" + AGENT_ID))
         .respond(response().withStatusCode(200));
     poller.run();
     verify(persistence, never()).loadLocalConfiguration();
@@ -52,7 +55,7 @@ void runLoadsLocalConfigurationOnlyOnceWhenConnectionFailed() {
   @Test
   void configurationRequestIsSentSuccessfully() {
     mockServer
-        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration"))
+        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration/" + AGENT_ID))
         .respond(response().withStatusCode(200));
 
     boolean successful = poller.pollConfiguration();

inspectit-gepard-agent/src/test/java/rocks/inspectit/gepard/agent/integrationtest/ConfigurationServerMock.java

@@ -8,8 +8,6 @@
 import java.io.IOException;
 import org.apache.commons.io.FileUtils;
 import org.mockserver.client.MockServerClient;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.testcontainers.containers.MockServerContainer;
 import org.testcontainers.containers.Network;
 import org.testcontainers.utility.DockerImageName;
@@ -22,8 +20,6 @@
  */
 public class ConfigurationServerMock {
 
-  private static final Logger logger = LoggerFactory.getLogger(ConfigurationServerMock.class);
-
   private MockServerContainer server;
   private MockServerClient serverClient;
 
@@ -56,7 +52,7 @@ public void configServerSetup(String config_path) throws IOException {
     String body = FileUtils.readFileToString(file, "UTF-8");
 
     serverClient
-        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration"))
+        .when(request().withMethod("GET").withPath("/api/v1/agent-configuration/.*"))
         .respond(response().withStatusCode(200).withBody(body));
 
     serverClient

inspectit-gepard-agent/src/test/java/rocks/inspectit/gepard/agent/internal/identity/IdentityManagerTest.java

@@ -7,16 +7,22 @@
 
 import java.lang.management.ManagementFactory;
 import java.lang.management.RuntimeMXBean;
+import java.lang.reflect.Field;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.MockedStatic;
 import org.mockito.Mockito;
-import org.mockito.junit.jupiter.MockitoExtension;
 import rocks.inspectit.gepard.agent.internal.identity.model.IdentityInfo;
 
-@ExtendWith(MockitoExtension.class)
 class IdentityManagerTest {
 
+  @BeforeEach
+  public void setup() throws NoSuchFieldException, IllegalAccessException {
+    Field instance = IdentityManager.class.getDeclaredField("instance");
+    instance.setAccessible(true);
+    instance.set(null, null);
+  }
+
   @Test
   void testCreateIdentityManagerSuccessfully() {
     RuntimeMXBean mockRuntimeMXBean = mock(RuntimeMXBean.class);
@@ -33,9 +39,7 @@ void testCreateIdentityManagerSuccessfully() {
 
       assertNotNull(identityInfo);
       assertEquals("12345@mockedHostName", identityInfo.vmId());
-      assertEquals(
-          "d29aca592fc2071bcef6577d649071d4d54a8ae6cd5c0be0e51f28af2867f207",
-          identityInfo.agentId());
+      assertNotNull(identityInfo.agentId());
     }
   }
 }