[ML] Fixing failing inference api streaming tests (elastic#118284)

* Fixing tests with alphanumeric strings

* Removing prints

Author: jonathan-buttner

muted-tests.yml

@@ -186,9 +186,6 @@ tests:
 - class: "org.elasticsearch.xpack.esql.qa.mixed.MixedClusterEsqlSpecIT"
   method: "test {scoring.*}"
   issue: https://github.com/elastic/elasticsearch/issues/117641
-- class: org.elasticsearch.xpack.inference.InferenceCrudIT
-  method: testSupportedStream
-  issue: https://github.com/elastic/elasticsearch/issues/117745
 - class: org.elasticsearch.xpack.esql.ccq.MultiClusterSpecIT
   method: test {scoring.QstrWithFieldAndScoringSortedEval}
   issue: https://github.com/elastic/elasticsearch/issues/117751
@@ -272,9 +269,6 @@ tests:
 - class: org.elasticsearch.packaging.test.ArchiveTests
   method: test51AutoConfigurationWithPasswordProtectedKeystore
   issue: https://github.com/elastic/elasticsearch/issues/118212
-- class: org.elasticsearch.xpack.inference.InferenceCrudIT
-  method: testUnifiedCompletionInference
-  issue: https://github.com/elastic/elasticsearch/issues/118210
 - class: org.elasticsearch.ingest.common.IngestCommonClientYamlTestSuiteIT
   issue: https://github.com/elastic/elasticsearch/issues/118215
 - class: org.elasticsearch.datastreams.DataStreamsClientYamlTestSuiteIT

test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java

@@ -277,6 +277,11 @@ public static void resetPortCounter() {
 
     private static final SetOnce<Boolean> WARN_SECURE_RANDOM_FIPS_NOT_DETERMINISTIC = new SetOnce<>();
 
+    private static final String LOWER_ALPHA_CHARACTERS = "abcdefghijklmnopqrstuvwxyz";
+    private static final String UPPER_ALPHA_CHARACTERS = LOWER_ALPHA_CHARACTERS.toUpperCase(Locale.ROOT);
+    private static final String DIGIT_CHARACTERS = "0123456789";
+    private static final String ALPHANUMERIC_CHARACTERS = LOWER_ALPHA_CHARACTERS + UPPER_ALPHA_CHARACTERS + DIGIT_CHARACTERS;
+
     static {
         Random random = initTestSeed();
         TEST_WORKER_VM_ID = System.getProperty(TEST_WORKER_SYS_PROPERTY, DEFAULT_TEST_WORKER_ID);
@@ -1200,6 +1205,21 @@ public static String randomAlphaOfLength(int codeUnits) {
         return RandomizedTest.randomAsciiOfLength(codeUnits);
     }
 
+    /**
+     * Generate a random string containing only alphanumeric characters.
+     * @param length the length of the string to generate
+     * @return the generated string
+     */
+    public static String randomAlphanumericOfLength(int length) {
+        StringBuilder sb = new StringBuilder();
+        Random random = random();
+        for (int i = 0; i < length; i++) {
+            sb.append(ALPHANUMERIC_CHARACTERS.charAt(random.nextInt(ALPHANUMERIC_CHARACTERS.length())));
+        }
+
+        return sb.toString();
+    }
+
     public static SecureString randomSecureStringOfLength(int codeUnits) {
         var randomAlpha = randomAlphaOfLength(codeUnits);
         return new SecureString(randomAlpha.toCharArray());

test/test-clusters/src/main/java/org/elasticsearch/test/cluster/FeatureFlag.java

@@ -18,7 +18,8 @@
 public enum FeatureFlag {
     TIME_SERIES_MODE("es.index_mode_feature_flag_registered=true", Version.fromString("8.0.0"), null),
     FAILURE_STORE_ENABLED("es.failure_store_feature_flag_enabled=true", Version.fromString("8.12.0"), null),
-    SUB_OBJECTS_AUTO_ENABLED("es.sub_objects_auto_feature_flag_enabled=true", Version.fromString("8.16.0"), null);
+    SUB_OBJECTS_AUTO_ENABLED("es.sub_objects_auto_feature_flag_enabled=true", Version.fromString("8.16.0"), null),
+    INFERENCE_UNIFIED_API_ENABLED("es.inference_unified_feature_flag_enabled=true", Version.fromString("8.18.0"), null);
 
     public final String systemProperty;
     public final Version from;

x-pack/plugin/inference/qa/inference-service-tests/src/javaRestTest/java/org/elasticsearch/xpack/inference/InferenceBaseRestTest.java

@@ -19,6 +19,7 @@
 import org.elasticsearch.core.Nullable;
 import org.elasticsearch.inference.TaskType;
 import org.elasticsearch.test.cluster.ElasticsearchCluster;
+import org.elasticsearch.test.cluster.FeatureFlag;
 import org.elasticsearch.test.cluster.local.distribution.DistributionType;
 import org.elasticsearch.test.rest.ESRestTestCase;
 import org.elasticsearch.xcontent.XContentBuilder;
@@ -46,6 +47,7 @@ public class InferenceBaseRestTest extends ESRestTestCase {
         .setting("xpack.security.enabled", "true")
         .plugin("inference-service-test")
         .user("x_pack_rest_user", "x-pack-test-password")
+        .feature(FeatureFlag.INFERENCE_UNIFIED_API_ENABLED)
         .build();
 
     @Override

x-pack/plugin/inference/qa/inference-service-tests/src/javaRestTest/java/org/elasticsearch/xpack/inference/InferenceCrudIT.java

@@ -466,7 +466,7 @@ public void testSupportedStream() throws Exception {
         assertEquals(modelId, singleModel.get("inference_id"));
         assertEquals(TaskType.COMPLETION.toString(), singleModel.get("task_type"));
 
-        var input = IntStream.range(1, 2 + randomInt(8)).mapToObj(i -> randomUUID()).toList();
+        var input = IntStream.range(1, 2 + randomInt(8)).mapToObj(i -> randomAlphanumericOfLength(5)).toList();
         try {
             var events = streamInferOnMockService(modelId, TaskType.COMPLETION, input);
 
@@ -493,7 +493,7 @@ public void testUnifiedCompletionInference() throws Exception {
         assertEquals(modelId, singleModel.get("inference_id"));
         assertEquals(TaskType.COMPLETION.toString(), singleModel.get("task_type"));
 
-        var input = IntStream.range(1, 2 + randomInt(8)).mapToObj(i -> randomUUID()).toList();
+        var input = IntStream.range(1, 2 + randomInt(8)).mapToObj(i -> randomAlphanumericOfLength(5)).toList();
         try {
             var events = unifiedCompletionInferOnMockService(modelId, TaskType.COMPLETION, input);
             var expectedResponses = expectedResultsIterator(input);