Minimal CelMatcher

Author: sergiitk

xds/src/main/java/io/grpc/xds/internal/matchers/CelMatcher.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2024 The gRPC Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.grpc.xds.internal.matchers;
+
+import java.util.function.Predicate;
+
+/** Unified Matcher API: xds.type.matcher.v3.CelMatcher. */
+public class CelMatcher implements Predicate<HttpMatchInput> {
+  private final String description;
+
+  public CelMatcher(String description) {
+    // TODO(sergiitk): cache parsed CEL expressions
+    this.description = description != null ? description : "";
+  }
+
+  public String description() {
+    return description;
+  }
+
+  @Override
+  public boolean test(HttpMatchInput httpMatchInput) {
+    if (httpMatchInput.headers().keys().isEmpty()) {
+      return false;
+    }
+    // TODO(sergiitk): [IMPL] convert headers to cel args
+    return true;
+  }
+}

xds/src/main/java/io/grpc/xds/internal/matchers/HttpMatchInput.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2024 The gRPC Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+package io.grpc.xds.internal.matchers;
+
+import com.google.auto.value.AutoValue;
+import io.grpc.Metadata;
+
+@AutoValue
+public abstract class HttpMatchInput {
+  public abstract Metadata headers();
+  // TODO(sergiitk): [IMPL] consider
+  // public abstract ServerCall<?, ?> serverCall();
+}

xds/src/main/java/io/grpc/xds/internal/rlqs/RlqsBucketSettings.java

@@ -20,19 +20,18 @@
 import com.google.common.base.Function;
 import com.google.common.collect.ImmutableMap;
 import com.google.protobuf.Duration;
-import io.grpc.Metadata;
+import io.grpc.xds.internal.matchers.HttpMatchInput;
 
 @AutoValue
 public abstract class RlqsBucketSettings {
 
-  public abstract ImmutableMap<String, Function<Metadata, String>> bucketIdBuilder();
+  public abstract ImmutableMap<String, Function<HttpMatchInput, String>> bucketIdBuilder();
 
   public abstract Duration reportingInterval();
 
   public static RlqsBucketSettings create(
-      ImmutableMap<String, Function<Metadata, String>> bucketIdBuilder,
+      ImmutableMap<String, Function<HttpMatchInput, String>> bucketIdBuilder,
       Duration reportingInterval) {
     return new AutoValue_RlqsBucketSettings(bucketIdBuilder, reportingInterval);
   }
-
 }

xds/src/test/java/io/grpc/xds/internal/matchers/CelMatcherTest.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2024 The gRPC Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.grpc.xds.internal.matchers;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class CelMatcherTest {
+
+  @Test
+  public void construct() {
+    String description = "Optional description";
+    CelMatcher matcher = new CelMatcher(description);
+    assertThat(matcher.description()).isEqualTo(description);
+
+    matcher = new CelMatcher(null);
+    assertThat(matcher.description()).isEqualTo("");
+  }
+}