Enable BI usage tracking for JCA. (Azure#21013)

Author: Rujun Chen

sdk/keyvault/azure-security-keyvault-jca/src/main/java/com/azure/security/keyvault/jca/LegacyRestClient.java

@@ -13,13 +13,25 @@
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.util.EntityUtils;
 
+import java.io.BufferedReader;
 import java.io.IOException;
+import java.io.InputStreamReader;
 import java.util.Map;
+import java.util.Optional;
+import java.util.stream.Stream;
 
 /**
  * The RestClient that uses the Apache HttpClient class.
  */
 class LegacyRestClient implements RestClient {
+    static final String USER_AGENT_KEY = "User-Agent";
+    static final String DEFAULT_USER_AGENT_VALUE_PREFIX = "az-se-kv-jca/";
+    static final String DEFAULT_VERSION = "unknown";
+    static final String VERSION = Optional.of(LegacyRestClient.class)
+                                          .map(Class::getPackage)
+                                          .map(Package::getImplementationVersion)
+                                          .orElse(DEFAULT_VERSION);
+    static final String USER_AGENT_VALUE = getUserAgentPrefix() + VERSION;
 
     /**
      * Constructor.
@@ -33,12 +45,9 @@ public String get(String url, Map<String, String> headers) {
         try (CloseableHttpClient client = HttpClients.createDefault()) {
             HttpGet httpGet = new HttpGet(url);
             if (headers != null) {
-                headers.entrySet().forEach(entry -> {
-                    String key = entry.getKey();
-                    String value = entry.getValue();
-                    httpGet.addHeader(key, value);
-                });
+                headers.forEach(httpGet::addHeader);
             }
+            httpGet.addHeader(USER_AGENT_KEY, USER_AGENT_VALUE);
             result = client.execute(httpGet, createResponseHandler());
         } catch (IOException ioe) {
             ioe.printStackTrace();
@@ -51,6 +60,7 @@ public String post(String url, String body, String contentType) {
         String result = null;
         try (CloseableHttpClient client = HttpClients.createDefault()) {
             HttpPost httpPost = new HttpPost(url);
+            httpPost.addHeader(USER_AGENT_KEY, USER_AGENT_VALUE);
             httpPost.setEntity(
                 new StringEntity(body, ContentType.create(contentType)));
             result = client.execute(httpPost, createResponseHandler());
@@ -60,6 +70,18 @@ public String post(String url, String body, String contentType) {
         return result;
     }
 
+    static String getUserAgentPrefix() {
+        return Optional.of(LegacyRestClient.class)
+                       .map(Class::getClassLoader)
+                       .map(c -> c.getResourceAsStream("azure-security-keyvault-jca-user-agent-value-prefix.txt"))
+                       .map(InputStreamReader::new)
+                       .map(BufferedReader::new)
+                       .map(BufferedReader::lines)
+                       .orElseGet(Stream::empty)
+                       .findFirst()
+                       .orElse(DEFAULT_USER_AGENT_VALUE_PREFIX);
+    }
+
     private ResponseHandler<String> createResponseHandler() {
         return (HttpResponse response) -> {
             int status = response.getStatusLine().getStatusCode();

sdk/keyvault/azure-security-keyvault-jca/src/test/java/com/azure/security/keyvault/jca/LegacyRestClientTest.java

@@ -5,19 +5,15 @@
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static com.azure.security.keyvault.jca.LegacyRestClient.DEFAULT_USER_AGENT_VALUE_PREFIX;
+import static com.azure.security.keyvault.jca.LegacyRestClient.DEFAULT_VERSION;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-/**
- * The JUnit tests for the LegacyRestClient class.
- */
 public class LegacyRestClientTest {
 
-    /**
-     * Test constructor.
-     */
     @Test
-    public void testConstructor() {
-        LegacyRestClient client = new LegacyRestClient();
-        assertNotNull(client);
+    public void getUserAgentPrefixTest() {
+        assertEquals(DEFAULT_USER_AGENT_VALUE_PREFIX, LegacyRestClient.getUserAgentPrefix());
+        assertEquals(DEFAULT_USER_AGENT_VALUE_PREFIX + DEFAULT_VERSION, LegacyRestClient.USER_AGENT_VALUE);
     }
 }

sdk/spring/azure-spring-boot-starter-keyvault-certificates/src/main/resources/azure-security-keyvault-jca-user-agent-value-prefix.txt

@@ -0,0 +1 @@
+az-sp-kv-ct/

sdk/spring/azure-spring-boot-starter-keyvault-certificates/src/test/java/com/azure/security/keyvault/jca/LegacyRestClientTest.java

@@ -0,0 +1,18 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.azure.security.keyvault.jca;
+
+import org.junit.jupiter.api.Test;
+
+import static com.azure.security.keyvault.jca.LegacyRestClient.DEFAULT_VERSION;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class LegacyRestClientTest {
+
+    @Test
+    public void getUserAgentPrefixTest() {
+        assertEquals("az-sp-kv-ct/", LegacyRestClient.getUserAgentPrefix());
+        assertEquals("az-sp-kv-ct/" + DEFAULT_VERSION, LegacyRestClient.USER_AGENT_VALUE);
+    }
+}