fix(grpc): add support for grpc service methods with underscores and reserved keywords in BlockingServerInterceptor

Author: Nicola Concetti

extensions/grpc/runtime/src/main/java/io/quarkus/grpc/runtime/supports/blocking/BlockingServerInterceptor.java

@@ -37,6 +37,62 @@
 public class BlockingServerInterceptor implements ServerInterceptor, Function<String, Boolean>, Prioritized {
     private static final Logger log = Logger.getLogger(BlockingServerInterceptor.class);
 
+    // Reserved keywords, based on the jls, see:
+    // https://github.com/grpc/grpc-java/blob/master/compiler/src/java_plugin/cpp/java_generator.cpp#L90
+    private static final Set<String> GRPC_JAVA_RESERVED_KEYWORDS = Set.of(
+            "abstract",
+            "assert",
+            "boolean",
+            "break",
+            "byte",
+            "case",
+            "catch",
+            "char",
+            "class",
+            "const",
+            "continue",
+            "default",
+            "do",
+            "double",
+            "else",
+            "enum",
+            "extends",
+            "final",
+            "finally",
+            "float",
+            "for",
+            "goto",
+            "if",
+            "implements",
+            "import",
+            "instanceof",
+            "int",
+            "interface",
+            "long",
+            "native",
+            "new",
+            "package",
+            "private",
+            "protected",
+            "public",
+            "return",
+            "short",
+            "static",
+            "strictfp",
+            "super",
+            "switch",
+            "synchronized",
+            "this",
+            "throw",
+            "throws",
+            "transient",
+            "try",
+            "void",
+            "volatile",
+            "while",
+            "true",
+            "false");
+
     private final Vertx vertx;
     private final Set<String> blockingMethods;
     private final Set<String> virtualMethods;
@@ -68,12 +124,22 @@ public BlockingServerInterceptor(Vertx vertx, List<String> blockingMethods, List
     @Override
     public Boolean apply(String name) {
         String methodName = name.substring(name.lastIndexOf("/") + 1);
-        return blockingMethods.contains(methodName.toLowerCase());
+        return blockingMethods.contains(toLowerCaseBeanSpec(methodName));
     }
 
     public Boolean applyVirtual(String name) {
         String methodName = name.substring(name.lastIndexOf("/") + 1);
-        return virtualMethods.contains(methodName.toLowerCase());
+        return virtualMethods.contains(toLowerCaseBeanSpec(methodName));
+    }
+
+    private String toLowerCaseBeanSpec(String name) {
+
+        // Methods cannot always be lowercased for comparison.
+        // - gRPC allows using method names which normally would not work in java because of reserved keywords.
+        // - Underscores are removed.
+
+        String lowerBeanSpec = name.toLowerCase().replace("_", "");
+        return GRPC_JAVA_RESERVED_KEYWORDS.contains(lowerBeanSpec) ? lowerBeanSpec + "_" : lowerBeanSpec;
     }
 
     @Override

extensions/grpc/runtime/src/test/java/io/quarkus/grpc/runtime/supports/BlockingServerInterceptorTest.java

@@ -5,6 +5,7 @@
 import static org.mockito.Mockito.when;
 
 import java.util.Collections;
+import java.util.List;
 import java.util.concurrent.CountDownLatch;
 
 import org.junit.jupiter.api.BeforeEach;
@@ -80,6 +81,85 @@ void testContextPropagation() throws Exception {
         }
     }
 
+    @Test
+    void testGrpcMethodMappingWithReservedKeywords() {
+        List<String> reservedKeywords = List.of(
+                "abstract",
+                "assert",
+                "boolean",
+                "break",
+                "byte",
+                "case",
+                "catch",
+                "char",
+                "class",
+                "const",
+                "continue",
+                "default",
+                "do",
+                "double",
+                "else",
+                "enum",
+                "extends",
+                "final",
+                "finally",
+                "float",
+                "for",
+                "goto",
+                "if",
+                "implements",
+                "import",
+                "instanceof",
+                "int",
+                "interface",
+                "long",
+                "native",
+                "new",
+                "package",
+                "private",
+                "protected",
+                "public",
+                "return",
+                "short",
+                "static",
+                "strictfp",
+                "super",
+                "switch",
+                "synchronized",
+                "this",
+                "throw",
+                "throws",
+                "transient",
+                "try",
+                "void",
+                "volatile",
+                "while",
+                "true",
+                "false");
+
+        List<String> javaMethodNames = reservedKeywords.stream().map(r -> r + "_").toList();
+        BlockingServerInterceptor interceptor = new BlockingServerInterceptor(vertx,
+                javaMethodNames, javaMethodNames, null, false) {
+        };
+
+        reservedKeywords
+                .forEach(reservedKeyword -> assertThat(interceptor.apply("my-service/" + reservedKeyword)).isTrue());
+        reservedKeywords
+                .forEach(reservedKeyword -> assertThat(interceptor.applyVirtual("my-service/" + reservedKeyword)).isTrue());
+    }
+
+    @Test
+    void testGrpcMethodMappingWithUnderscores() {
+
+        String javaMethodName = "javabeanspec";
+        BlockingServerInterceptor interceptor = new BlockingServerInterceptor(vertx,
+                Collections.singletonList(javaMethodName), Collections.singletonList(javaMethodName), null, false) {
+        };
+
+        assertThat(interceptor.apply("my-service/J_Ava_BeanSpec")).isTrue();
+        assertThat(interceptor.applyVirtual("my-service/J_Ava_BeanSpec")).isTrue();
+    }
+
     static class BlockingServerCallHandler implements ServerCallHandler {
         String threadName;
         String contextUserName;