Python: Add routing header

src/main/java/com/google/api/codegen/transformer/ApiCallableTransformer.java

@@ -16,27 +16,21 @@
 
 import com.google.api.codegen.config.DiscoveryMethodModel;
 import com.google.api.codegen.config.FieldModel;
-import com.google.api.codegen.config.GapicMethodConfig;
 import com.google.api.codegen.config.MethodConfig;
 import com.google.api.codegen.config.MethodModel;
 import com.google.api.codegen.config.PageStreamingConfig;
-import com.google.api.codegen.config.ProtoField;
 import com.google.api.codegen.config.TransportProtocol;
 import com.google.api.codegen.config.VisibilityConfig;
 import com.google.api.codegen.discovery.Method;
 import com.google.api.codegen.viewmodel.ApiCallSettingsView;
 import com.google.api.codegen.viewmodel.ApiCallableImplType;
 import com.google.api.codegen.viewmodel.ApiCallableView;
-import com.google.api.codegen.viewmodel.HeaderRequestParamView;
 import com.google.api.codegen.viewmodel.HttpMethodView;
 import com.google.api.codegen.viewmodel.LongRunningOperationDetailView;
 import com.google.api.codegen.viewmodel.MethodDescriptorView;
 import com.google.api.codegen.viewmodel.RetryCodesDefinitionView;
 import com.google.api.codegen.viewmodel.RetryParamsDefinitionView;
 import com.google.api.codegen.viewmodel.ServiceMethodType;
-import com.google.api.tools.framework.model.Field;
-import com.google.api.tools.framework.model.MessageType;
-import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -48,11 +42,13 @@ public class ApiCallableTransformer {
   private final BatchingTransformer batchingTransformer;
   private final RetryDefinitionsTransformer retryDefinitionsTransformer;
   private final LongRunningTransformer lroTransformer;
+  private final HeaderRequestParamTransformer headerRequestParamTransformer;
 
   public ApiCallableTransformer() {
     this.batchingTransformer = new BatchingTransformer();
     this.retryDefinitionsTransformer = new RetryDefinitionsTransformer();
     this.lroTransformer = new LongRunningTransformer();
+    this.headerRequestParamTransformer = new HeaderRequestParamTransformer();
   }
 
   public List<ApiCallableView> generateStaticLangApiCallables(InterfaceContext context) {
@@ -116,7 +112,8 @@ private ApiCallableView generateMainApiCallable(MethodContext context) {
     apiCallableBuilder.memberName(namer.getSettingsMemberName(method));
     apiCallableBuilder.settingsFunctionName(namer.getSettingsFunctionName(method));
     apiCallableBuilder.grpcClientVarName(namer.getReroutedGrpcClientVarName(methodConfig));
-    apiCallableBuilder.headerRequestParams(getHeaderRequestParams(context));
+    apiCallableBuilder.headerRequestParams(
+        headerRequestParamTransformer.generateHeaderRequestParams(context));
 
     setCommonApiCallableFields(context, apiCallableBuilder);
 
@@ -380,62 +377,11 @@ private MethodDescriptorView generateMethodDescriptor(MethodContext context) {
     methodDescriptorBuilder.fullServiceName(context.getTargetInterface().getFullName());
     methodDescriptorBuilder.transportSettingsVar(namer.getTransportSettingsVar(method));
 
-    methodDescriptorBuilder.headerRequestParams(getHeaderRequestParams(context));
+    methodDescriptorBuilder.headerRequestParams(
+        headerRequestParamTransformer.generateHeaderRequestParams(context));
 
     methodDescriptorBuilder.httpMethod(generateHttpFields(context));
 
     return methodDescriptorBuilder.build();
   }
-
-  public static List<HeaderRequestParamView> getHeaderRequestParams(MethodContext context) {
-    if (!context.getProductConfig().getTransportProtocol().equals(TransportProtocol.GRPC)) {
-      return ImmutableList.of();
-    }
-
-    GapicMethodConfig methodConfig = (GapicMethodConfig) context.getMethodConfig();
-    com.google.api.tools.framework.model.Method method = methodConfig.getMethod();
-    SurfaceNamer namer = context.getNamer();
-    if (method.getInputType() == null || !method.getInputType().isMessage()) {
-      return ImmutableList.of();
-    }
-    ImmutableList.Builder<HeaderRequestParamView> headerRequestParams = ImmutableList.builder();
-    MessageType inputMessageType = method.getInputType().getMessageType();
-    for (String headerRequestParam : methodConfig.getHeaderRequestParams()) {
-      headerRequestParams.add(getHeaderRequestParam(headerRequestParam, inputMessageType, namer));
-    }
-
-    return headerRequestParams.build();
-  }
-
-  private static HeaderRequestParamView getHeaderRequestParam(
-      String headerRequestParam, MessageType inputMessageType, SurfaceNamer namer) {
-    String[] fieldNameTokens = headerRequestParam.split("\\.");
-    ImmutableList.Builder<String> gettersChain = ImmutableList.builder();
-
-    MessageType subMessageType = inputMessageType;
-    for (String fieldNameToken : fieldNameTokens) {
-      Field matchingField = subMessageType.lookupField(fieldNameToken);
-      if (matchingField == null) {
-        throw new IllegalArgumentException(
-            "Unknown field name token '"
-                + fieldNameToken
-                + "' in header request param '"
-                + headerRequestParam
-                + "'");
-      }
-
-      String matchingFieldGetter = namer.getFieldGetFunctionName(new ProtoField(matchingField));
-      gettersChain.add(matchingFieldGetter);
-      if (matchingField.getType() != null && matchingField.getType().isMessage()) {
-        subMessageType = matchingField.getType().getMessageType();
-      }
-    }
-
-    HeaderRequestParamView.Builder headerParam =
-        HeaderRequestParamView.newBuilder()
-            .fullyQualifiedName(headerRequestParam)
-            .gettersChain(gettersChain.build());
-
-    return headerParam.build();
-  }
 }

src/main/java/com/google/api/codegen/transformer/DynamicLangApiMethodTransformer.java

@@ -41,6 +41,8 @@ public class DynamicLangApiMethodTransformer {
   private final ApiMethodParamTransformer apiMethodParamTransformer;
   private final InitCodeTransformer initCodeTransformer;
   private final LongRunningTransformer lroTransformer = new LongRunningTransformer();
+  private final HeaderRequestParamTransformer headerRequestParamTransformer =
+      new HeaderRequestParamTransformer();
   private final PageStreamingTransformer pageStreamingTransformer = new PageStreamingTransformer();
 
   public DynamicLangApiMethodTransformer(ApiMethodParamTransformer apiMethodParamTransformer) {
@@ -139,6 +141,8 @@ public OptionalArrayMethodView generateMethod(
             : null);
 
     apiMethod.oneofParams(context.getMethodConfig().getOneofNames(namer));
+    apiMethod.headerRequestParams(
+        headerRequestParamTransformer.generateHeaderRequestParams(context));
 
     return apiMethod.build();
   }

src/main/java/com/google/api/codegen/transformer/HeaderRequestParamTransformer.java

@@ -0,0 +1,80 @@
+/* Copyright 2017 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.codegen.transformer;
+
+import com.google.api.codegen.config.GapicMethodConfig;
+import com.google.api.codegen.config.ProtoField;
+import com.google.api.codegen.config.TransportProtocol;
+import com.google.api.codegen.viewmodel.HeaderRequestParamView;
+import com.google.api.tools.framework.model.Field;
+import com.google.api.tools.framework.model.MessageType;
+import com.google.api.tools.framework.model.Method;
+import com.google.common.collect.ImmutableList;
+import java.util.List;
+
+public class HeaderRequestParamTransformer {
+  public List<HeaderRequestParamView> generateHeaderRequestParams(MethodContext context) {
+    if (!context.getProductConfig().getTransportProtocol().equals(TransportProtocol.GRPC)) {
+      return ImmutableList.of();
+    }
+
+    GapicMethodConfig methodConfig = (GapicMethodConfig) context.getMethodConfig();
+    Method method = methodConfig.getMethod();
+    SurfaceNamer namer = context.getNamer();
+    if (method.getInputType() == null || !method.getInputType().isMessage()) {
+      return ImmutableList.of();
+    }
+    ImmutableList.Builder<HeaderRequestParamView> headerRequestParams = ImmutableList.builder();
+    MessageType inputMessageType = method.getInputType().getMessageType();
+    for (String headerRequestParam : methodConfig.getHeaderRequestParams()) {
+      headerRequestParams.add(
+          generateHeaderRequestParam(headerRequestParam, inputMessageType, namer));
+    }
+
+    return headerRequestParams.build();
+  }
+
+  private HeaderRequestParamView generateHeaderRequestParam(
+      String headerRequestParam, MessageType inputMessageType, SurfaceNamer namer) {
+    String[] fieldNameTokens = headerRequestParam.split("\\.");
+    ImmutableList.Builder<String> gettersChain = ImmutableList.builder();
+
+    MessageType subMessageType = inputMessageType;
+    for (String fieldNameToken : fieldNameTokens) {
+      Field matchingField = subMessageType.lookupField(fieldNameToken);
+      if (matchingField == null) {
+        throw new IllegalArgumentException(
+            "Unknown field name token '"
+                + fieldNameToken
+                + "' in header request param '"
+                + headerRequestParam
+                + "'");
+      }
+
+      String matchingFieldGetter = namer.getFieldGetFunctionName(new ProtoField(matchingField));
+      gettersChain.add(matchingFieldGetter);
+      if (matchingField.getType() != null && matchingField.getType().isMessage()) {
+        subMessageType = matchingField.getType().getMessageType();
+      }
+    }
+
+    HeaderRequestParamView.Builder headerParam =
+        HeaderRequestParamView.newBuilder()
+            .fullyQualifiedName(headerRequestParam)
+            .gettersChain(gettersChain.build());
+
+    return headerParam.build();
+  }
+}

src/main/java/com/google/api/codegen/transformer/StaticLangApiMethodTransformer.java

@@ -56,6 +56,8 @@ public class StaticLangApiMethodTransformer {
   private final LongRunningTransformer lroTransformer = new LongRunningTransformer();
   private final StaticLangResourceObjectTransformer resourceObjectTransformer =
       new StaticLangResourceObjectTransformer();
+  private final HeaderRequestParamTransformer headerRequestParamTransformer =
+      new HeaderRequestParamTransformer();
 
   public StaticLangApiMethodView generatePagedFlattenedMethod(MethodContext context) {
     return generatePagedFlattenedMethod(context, Collections.<ParamWithSimpleDoc>emptyList());
@@ -489,7 +491,8 @@ private void setCommonFields(
     } else {
       methodViewBuilder.hasReturnValue(method.hasReturnValue());
     }
-    methodViewBuilder.headerRequestParams(ApiCallableTransformer.getHeaderRequestParams(context));
+    methodViewBuilder.headerRequestParams(
+        headerRequestParamTransformer.generateHeaderRequestParams(context));
   }
 
   protected void setServiceResponseTypeName(

src/main/java/com/google/api/codegen/viewmodel/OptionalArrayMethodView.java

@@ -104,6 +104,8 @@ public boolean hasApiVersion() {
 
   public abstract Iterable<Iterable<String>> oneofParams();
 
+  public abstract List<HeaderRequestParamView> headerRequestParams();
+
   public static Builder newBuilder() {
     return new AutoValue_OptionalArrayMethodView.Builder();
   }
@@ -182,6 +184,8 @@ public abstract Builder optionalRequestObjectParamsNoPageToken(
 
     public abstract Builder localPackageName(String val);
 
+    public abstract Builder headerRequestParams(List<HeaderRequestParamView> val);
+
     public abstract OptionalArrayMethodView build();
   }
 }

src/main/resources/com/google/api/codegen/py/main.snip

@@ -242,7 +242,7 @@
 
 @private callLine(apiMethod)
     @if apiMethod.isLongRunningOperation
-        operation = self._{@apiMethod.name}({@apiMethod.requestVariableName}, retry=retry, timeout=timeout)
+        operation = self._{@apiMethod.name}({@apiMethod.requestVariableName}{@optionalParams(apiMethod)})
         return google.api_core.operation.from_gapic(
             operation,
             self.operations_client,
@@ -252,14 +252,14 @@
         @switch apiMethod.type
         @case "OptionalArrayMethod"
             @if apiMethod.hasReturnValue
-                return self._{@apiMethod.name}({@apiMethod.requestVariableName}, retry=retry, timeout=timeout)
+                return self._{@apiMethod.name}({@apiMethod.requestVariableName}{@optionalParams(apiMethod)})
             @else
-                self._{@apiMethod.name}({@apiMethod.requestVariableName}, retry=retry, timeout=timeout)
+                self._{@apiMethod.name}({@apiMethod.requestVariableName}{@optionalParams(apiMethod)})
             @end
         @case "PagedOptionalArrayMethod"
             iterator = google.api_core.page_iterator.GRPCIterator(
                 client=None,
-                method=functools.partial(self._{@apiMethod.name}, retry=retry, timeout=timeout),
+                method=functools.partial(self._{@apiMethod.name}{@optionalParams(apiMethod)}),
                 request={@apiMethod.requestVariableName},
                 items_field='{@apiMethod.pageStreamingView.resourcesFieldName}',
                 request_token_field='{@apiMethod.pageStreamingView.requestTokenFieldName}',
@@ -271,6 +271,14 @@
     @end
 @end
 
+@private optionalParams(apiMethod)
+    @if apiMethod.headerRequestParams
+        , retry=retry, timeout=timeout, metadata=metadata
+    @else
+        , retry=retry, timeout=timeout
+    @end
+@end
+
 @private flattenedMethod(apiMethod)
     def {@apiMethod.name}(
             {@renderMethodParams(apiMethod.methodParams)}):
@@ -297,6 +305,14 @@
                     request = {@apiMethod.requestTypeName}()
                 @end
             @end
+
+            @if apiMethod.headerRequestParams
+
+                metadata = [
+                    (b'x-google-request-params',
+                     {@routingHeader(apiMethod.headerRequestParams)})]
+
+            @end
         @end
         {@callLine(apiMethod)}
 @end
@@ -329,3 +345,25 @@
         {@param.keyName}={@param.name}
     @end
 @end
+
+@private routingHeader(params)
+  b'{@routingHeaderFmtStr(params)}'.format({@routingHeaderFmtArgs(params)})
+@end
+
+@private routingHeaderFmtStr(params)
+    @join param : params on "&"
+        {@param.fullyQualifiedName}={}
+    @end
+@end
+
+@private routingHeaderFmtArgs(params)
+    @join param : params on ", "
+        {@routingHeaderGetters(param.gettersChain)}
+    @end
+@end
+
+@private routingHeaderGetters(getters)
+    @join getter : getters on "."
+        {@getter}
+    @end
+@end

src/test/java/com/google/api/codegen/testdata/py/py_library.baseline

@@ -1532,7 +1532,12 @@ class LibraryServiceClient(object):
         request = library_pb2.CreateBookRequest(
             name=name,
             book=book)
-        return self._create_book(request, retry=retry, timeout=timeout)
+
+        metadata = [
+            (b'x-google-request-params',
+             b'name={}&book.read={}'.format(name, book.read))]
+
+        return self._create_book(request, retry=retry, timeout=timeout, metadata=metadata)
 
     def publish_series(
             self,