[ggj] fix: refactor parsed data into GapicContext (#154)

* feat: add initial resource name def parsing

* feat: add early failure for missing fields

* feat: couple resnames and message parsing

* fix!: refactor method arg parsing away from class creation

* feat: add resource_reference parsing

* fix: dot name parsing

src/main/java/com/google/api/generator/gapic/Generator.java

@@ -16,21 +16,18 @@
 
 import com.google.api.generator.gapic.composer.Composer;
 import com.google.api.generator.gapic.model.GapicClass;
-import com.google.api.generator.gapic.model.Message;
-import com.google.api.generator.gapic.model.Service;
+import com.google.api.generator.gapic.model.GapicContext;
 import com.google.api.generator.gapic.protoparser.Parser;
 import com.google.api.generator.gapic.protowriter.Writer;
 import com.google.protobuf.compiler.PluginProtos.CodeGeneratorRequest;
 import com.google.protobuf.compiler.PluginProtos.CodeGeneratorResponse;
 import java.util.List;
-import java.util.Map;
 
 public class Generator {
   public static CodeGeneratorResponse generateGapic(
       CodeGeneratorRequest request, String outputFilePath) {
-    Map<String, Message> messageTypes = Parser.parseMessages(request);
-    List<Service> services = Parser.parseServices(request, messageTypes);
-    List<GapicClass> clazzes = Composer.composeServiceClasses(services, messageTypes);
+    GapicContext context = Parser.parse(request);
+    List<GapicClass> clazzes = Composer.composeServiceClasses(context);
     CodeGeneratorResponse response = Writer.writeCode(clazzes, outputFilePath);
     return response;
   }

src/main/java/com/google/api/generator/gapic/composer/Composer.java

@@ -18,6 +18,7 @@
 import com.google.api.generator.engine.ast.ScopeNode;
 import com.google.api.generator.gapic.model.GapicClass;
 import com.google.api.generator.gapic.model.GapicClass.Kind;
+import com.google.api.generator.gapic.model.GapicContext;
 import com.google.api.generator.gapic.model.Message;
 import com.google.api.generator.gapic.model.Service;
 import java.util.ArrayList;
@@ -26,11 +27,10 @@
 import javax.annotation.Nonnull;
 
 public class Composer {
-  public static List<GapicClass> composeServiceClasses(
-      @Nonnull List<Service> services, @Nonnull Map<String, Message> messageTypes) {
+  public static List<GapicClass> composeServiceClasses(GapicContext context) {
     List<GapicClass> clazzes = new ArrayList<>();
-    for (Service service : services) {
-      clazzes.addAll(generateServiceClasses(service, messageTypes));
+    for (Service service : context.services()) {
+      clazzes.addAll(generateServiceClasses(service, context.messages()));
     }
     return clazzes;
   }

src/main/java/com/google/api/generator/gapic/model/GapicContext.java

@@ -0,0 +1,47 @@
+// Copyright 2020 Google LLC
+//
+// 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 com.google.api.generator.gapic.model;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import java.util.List;
+import java.util.Map;
+
+@AutoValue
+public abstract class GapicContext {
+  // Maps the message name (as it appears in the protobuf) to Messages.
+  public abstract ImmutableMap<String, Message> messages();
+
+  // Maps the resource type string to ResourceNames.
+  public abstract ImmutableMap<String, ResourceName> resourceNames();
+
+  public abstract ImmutableList<Service> services();
+
+  public static Builder builder() {
+    return new AutoValue_GapicContext.Builder();
+  }
+
+  @AutoValue.Builder
+  public abstract static class Builder {
+    public abstract Builder setMessages(Map<String, Message> messages);
+
+    public abstract Builder setResourceNames(Map<String, ResourceName> resourceNames);
+
+    public abstract Builder setServices(List<Service> services);
+
+    public abstract GapicContext build();
+  }
+}

src/main/java/com/google/api/generator/gapic/protoparser/Parser.java

@@ -19,6 +19,7 @@
 import com.google.api.generator.engine.ast.TypeNode;
 import com.google.api.generator.engine.ast.VaporReference;
 import com.google.api.generator.gapic.model.Field;
+import com.google.api.generator.gapic.model.GapicContext;
 import com.google.api.generator.gapic.model.LongrunningOperation;
 import com.google.api.generator.gapic.model.Message;
 import com.google.api.generator.gapic.model.Method;
@@ -57,6 +58,21 @@ public GapicParserException(String errorMessage) {
     }
   }
 
+  public static GapicContext parse(CodeGeneratorRequest request) {
+    // Keep message and resource name parsing separate for cleaner logic.
+    // While this takes an extra pass through the protobufs, the extra time is relatively trivial
+    // and is worth the larger reduced maintenance cost.
+    Map<String, Message> messages = parseMessages(request);
+    Map<String, ResourceName> resourceNames = parseResourceNames(request);
+    messages = updateResourceNamesInMessages(messages, resourceNames.values());
+    List<Service> services = parseServices(request, messages);
+    return GapicContext.builder()
+        .setServices(services)
+        .setMessages(messages)
+        .setResourceNames(resourceNames)
+        .build();
+  }
+
   public static List<Service> parseServices(
       CodeGeneratorRequest request, Map<String, Message> messageTypes) {
     Map<String, FileDescriptor> fileDescriptors = getFilesToGenerate(request);