Allow specifying additional HttpRules for gRPC/JSON transcoding

grpc/src/main/java/com/linecorp/armeria/server/grpc/DefaultHttpJsonTranscodingOptions.java

@@ -16,24 +16,42 @@
 
 package com.linecorp.armeria.server.grpc;
 
+import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 
+import com.google.api.HttpRule;
 import com.google.common.base.MoreObjects;
 
 final class DefaultHttpJsonTranscodingOptions implements HttpJsonTranscodingOptions {
 
     static final HttpJsonTranscodingOptions DEFAULT = HttpJsonTranscodingOptions.builder().build();
 
+    private final boolean useHttpAnnotations;
+    private final List<HttpRule> additionalHttpRules;
     private final Set<HttpJsonTranscodingQueryParamMatchRule> queryParamMatchRules;
     private final UnframedGrpcErrorHandler errorHandler;
 
-    DefaultHttpJsonTranscodingOptions(Set<HttpJsonTranscodingQueryParamMatchRule> queryParamMatchRules,
+    DefaultHttpJsonTranscodingOptions(boolean useHttpAnnotations,
+                                      List<HttpRule> additionalHttpRules,
+                                      Set<HttpJsonTranscodingQueryParamMatchRule> queryParamMatchRules,
                                       UnframedGrpcErrorHandler errorHandler) {
+        this.useHttpAnnotations = useHttpAnnotations;
+        this.additionalHttpRules = additionalHttpRules;
         this.queryParamMatchRules = queryParamMatchRules;
         this.errorHandler = errorHandler;
     }
 
+    @Override
+    public boolean useHttpAnnotations() {
+        return useHttpAnnotations;
+    }
+
+    @Override
+    public List<HttpRule> additionalHttpRules() {
+        return additionalHttpRules;
+    }
+
     @Override
     public Set<HttpJsonTranscodingQueryParamMatchRule> queryParamMatchRules() {
         return queryParamMatchRules;
@@ -53,18 +71,22 @@ public boolean equals(Object o) {
             return false;
         }
         final HttpJsonTranscodingOptions that = (HttpJsonTranscodingOptions) o;
-        return queryParamMatchRules.equals(that.queryParamMatchRules()) &&
+        return useHttpAnnotations == that.useHttpAnnotations() &&
+               additionalHttpRules.equals(that.additionalHttpRules()) &&
+               queryParamMatchRules.equals(that.queryParamMatchRules()) &&
                errorHandler.equals(that.errorHandler());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(queryParamMatchRules, errorHandler);
+        return Objects.hash(useHttpAnnotations, additionalHttpRules, queryParamMatchRules, errorHandler);
     }
 
     @Override
     public String toString() {
         return MoreObjects.toStringHelper(this)
+                          .add("useHttpAnnotations", useHttpAnnotations)
+                          .add("additionalHttpRules", additionalHttpRules)
                           .add("queryParamMatchRules", queryParamMatchRules)
                           .add("errorHandler", errorHandler)
                           .toString();

grpc/src/main/java/com/linecorp/armeria/server/grpc/GrpcServiceBuilder.java

@@ -1070,16 +1070,14 @@ public GrpcService build() {
             final HttpJsonTranscodingOptions httpJsonTranscodingOptions;
             if (httpJsonTranscodingErrorHandler != null) {
                 httpJsonTranscodingOptions =
-                        HttpJsonTranscodingOptions
-                                .builder()
-                                .queryParamMatchRules(
-                                        this.httpJsonTranscodingOptions.queryParamMatchRules())
+                        new HttpJsonTranscodingOptionsBuilder(this.httpJsonTranscodingOptions)
                                 .errorHandler(httpJsonTranscodingErrorHandler)
                                 .build();
             } else {
                 httpJsonTranscodingOptions = this.httpJsonTranscodingOptions;
             }
-            grpcService = HttpJsonTranscodingService.of(grpcService, httpJsonTranscodingOptions);
+            grpcService = HttpJsonTranscodingServiceBuilder.of(grpcService, httpJsonTranscodingOptions)
+                                                           .build();
         }
         if (handlerRegistry.containsDecorators()) {
             grpcService = new GrpcDecoratingService(grpcService, handlerRegistry);

grpc/src/main/java/com/linecorp/armeria/server/grpc/HttpJsonTranscodingOptions.java

@@ -16,8 +16,10 @@
 
 package com.linecorp.armeria.server.grpc;
 
+import java.util.List;
 import java.util.Set;
 
+import com.google.api.HttpRule;
 import com.google.protobuf.Message;
 
 import com.linecorp.armeria.common.annotation.UnstableApi;
@@ -42,6 +44,21 @@ static HttpJsonTranscodingOptions of() {
         return DefaultHttpJsonTranscodingOptions.DEFAULT;
     }
 
+    /**
+     * Returns whether to extract and register HTTP/JSON transcoding rules from {@code google.api.http}
+     * annotations in proto descriptors. When {@code true}, methods with {@code google.api.http} options
+     * are automatically registered as HTTP/JSON endpoints according to their annotation specifications.
+     * This option is enabled by default.
+     */
+    boolean useHttpAnnotations();
+
+    /**
+     * Returns additional HTTP/JSON transcoding rules that supplement annotation-based rules. These rules
+     * allow programmatic configuration of HTTP/JSON transcoding without modifying proto files. The rules are
+     * processed regardless of the {@link #useHttpAnnotations()} setting. Returns an empty list by default.
+     */
+    List<HttpRule> additionalHttpRules();
+
     /**
      * Returns the {@link HttpJsonTranscodingQueryParamMatchRule}s which is used to match fields in a
      * {@link Message} with query parameters.

grpc/src/main/java/com/linecorp/armeria/server/grpc/HttpJsonTranscodingOptionsBuilder.java

@@ -22,8 +22,10 @@
 import static java.util.Objects.requireNonNull;
 
 import java.util.EnumSet;
+import java.util.List;
 import java.util.Set;
 
+import com.google.api.HttpRule;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
@@ -46,13 +48,27 @@ public final class HttpJsonTranscodingOptionsBuilder {
     private static final EnumSet<HttpJsonTranscodingQueryParamMatchRule> DEFAULT_QUERY_PARAM_MATCH_RULES =
             EnumSet.of(JSON_NAME, ORIGINAL_FIELD);
 
+    private final ImmutableList.Builder<HttpRule> additionalHttpRules = ImmutableList.builder();
+
+    private boolean useHttpAnnotations = true;
+
     private UnframedGrpcErrorHandler errorHandler = UnframedGrpcErrorHandler.ofJson();
 
     @Nullable
     private Set<HttpJsonTranscodingQueryParamMatchRule> queryParamMatchRules;
 
     HttpJsonTranscodingOptionsBuilder() {}
 
+    /**
+     * A copy constructor.
+     */
+    HttpJsonTranscodingOptionsBuilder(HttpJsonTranscodingOptions options) {
+        useHttpAnnotations(options.useHttpAnnotations());
+        additionalHttpRules(options.additionalHttpRules());
+        queryParamMatchRules(options.queryParamMatchRules());
+        errorHandler(options.errorHandler());
+    }
+
     /**
      * Adds the specified {@link HttpJsonTranscodingQueryParamMatchRule} which is used
      * to match {@link QueryParams} of an {@link HttpRequest} with fields in a {@link Message}.
@@ -81,6 +97,38 @@ public HttpJsonTranscodingOptionsBuilder queryParamMatchRules(
         return this;
     }
 
+    /**
+     * Sets whether to extract and register HTTP/JSON transcoding rules from {@code google.api.http}
+     * annotations in proto descriptors. When {@code true}, methods with {@code google.api.http} options
+     * are automatically registered as HTTP/JSON endpoints according to their annotation specifications.
+     * This option is enabled by default.
+     */
+    public HttpJsonTranscodingOptionsBuilder useHttpAnnotations(boolean useHttpAnnotations) {
+        this.useHttpAnnotations = useHttpAnnotations;
+        return this;
+    }
+
+    /**
+     * Adds additional HTTP/JSON transcoding rules that supplement annotation-based rules. These rules
+     * allow programmatic configuration of HTTP/JSON transcoding without modifying proto files. The rules are
+     * processed regardless of the {@link #useHttpAnnotations(boolean)} setting.
+     */
+    public HttpJsonTranscodingOptionsBuilder additionalHttpRules(HttpRule... rules) {
+        requireNonNull(rules, "rules");
+        return additionalHttpRules(ImmutableList.copyOf(rules));
+    }
+
+    /**
+     * Adds additional HTTP/JSON transcoding rules that supplement annotation-based rules. These rules
+     * allow programmatic configuration of HTTP/JSON transcoding without modifying proto files. The rules are
+     * processed regardless of the {@link #useHttpAnnotations(boolean)} setting.
+     */
+    public HttpJsonTranscodingOptionsBuilder additionalHttpRules(Iterable<HttpRule> rules) {
+        requireNonNull(rules, "rules");
+        additionalHttpRules.addAll(rules);
+        return this;
+    }
+
     /**
      * Sets an error handler which handles an exception raised while serving a gRPC request transcoded from
      * an HTTP/JSON request. By default, {@link UnframedGrpcErrorHandler#ofJson()} would be set.
@@ -96,6 +144,7 @@ public HttpJsonTranscodingOptionsBuilder errorHandler(UnframedGrpcErrorHandler e
      * Returns a newly created {@link HttpJsonTranscodingOptions}.
      */
     public HttpJsonTranscodingOptions build() {
+        final List<HttpRule> rules = additionalHttpRules.build();
         final Set<HttpJsonTranscodingQueryParamMatchRule> matchRules;
         if (queryParamMatchRules == null) {
             matchRules = DEFAULT_QUERY_PARAM_MATCH_RULES;
@@ -112,6 +161,6 @@ public HttpJsonTranscodingOptions build() {
                 matchRules = ImmutableSet.copyOf(queryParamMatchRules);
             }
         }
-        return new DefaultHttpJsonTranscodingOptions(matchRules, errorHandler);
+        return new DefaultHttpJsonTranscodingOptions(useHttpAnnotations, rules, matchRules, errorHandler);
     }
 }