Federation mvp (#48)

* DOS-1266: intial federation key support

* Allowing transformer to see federation interface entites

* Change the service type

* Change resource set builder to concatenate files to read defaults only once and rename service type to federation subgraph

* Federation entity collection

* federation shared types support

* add method for isFederatedProvider

* rename entities variable to entitiesByTypeName

* entity-type-merging: initial commit

* federation metadata classes

* Support for FieldSet scalar

* intital federation require support

* make exceptions more generic to apply to more directives and fix shared type edge case

* KeyTransformPostmerge integration and adding test

* Verify keys defined in extension are a subset of the base entity

* collecting key directives in FederationMetadata

* removing entity batching

* enrich entity's selection set if keys are not selected

* use base entity keys for representation

* resolve required fields during normal field resolution instead as an entity fetch request

* ensure extension fields are not in base, and refactor exceptions to be in package

* Federation support for type extension

* DOS-1386: merging of value type support

* validate fetches entity response

* Add new constant for response and refactor to use constants

* Add validation for entity fetcher

Co-authored-by: Ashpak Shaikh <[email protected]>
Co-authored-by: kmoore-intuit <[email protected]>
Co-authored-by: Aureus, Carlo <[email protected]>
Co-authored-by: kmoore15 <[email protected]>
Co-authored-by: Shaikh <[email protected]>

Author: 4 people

pom.xml

@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.intuit.graphql</groupId>
   <artifactId>graphql-orchestrator-java</artifactId>
-  <version>4.1.8-SNAPSHOT</version>
+  <version>5.0.0-SNAPSHOT</version>
   <packaging>jar</packaging>
   <name>graphql-orchestrator-java</name>
   <description>GraphQL Orchestrator combines multiple graphql services into a single unified schema</description>
@@ -37,7 +37,7 @@
     <maven.compiler.plugin.version>3.8.1</maven.compiler.plugin.version>
     <awssdk2.version>2.7.2</awssdk2.version>
     <graphql-sdl-version>3.0.1</graphql-sdl-version>
-    <xtextVersion>2.25.0</xtextVersion>
+    <xtextVersion>2.26.0</xtextVersion>
     <graphQLVersion>17.3</graphQLVersion>
   </properties>
 
@@ -377,7 +377,7 @@
     <connection>scm:git:https://github.com/intuit/graphql-orchestrator-java
     </connection>
     <url>https://github.com/intuit/graphql-orchestrator-java</url>
-    <tag>graphql-orchestrator-java-4.0.12</tag>
+    <tag>graphql-orchestrator-java-5.0.0-beta3</tag>
   </scm>
 
   <distributionManagement>

src/main/java/com/intuit/graphql/orchestrator/batch/NoExternalReferenceSelectionSetModifier.java renamed to src/main/java/com/intuit/graphql/orchestrator/batch/DownstreamQueryModifier.java

@@ -7,6 +7,8 @@
 import static graphql.util.TreeTransformerUtil.deleteNode;
 import static java.util.Objects.requireNonNull;
 
+import com.intuit.graphql.orchestrator.federation.RequiredFieldsCollector;
+import com.intuit.graphql.orchestrator.federation.metadata.FederationMetadata;
 import com.intuit.graphql.orchestrator.schema.ServiceMetadata;
 import com.intuit.graphql.orchestrator.schema.transform.FieldResolverContext;
 import com.intuit.graphql.orchestrator.utils.SelectionCollector;
@@ -24,23 +26,37 @@
 import graphql.schema.GraphQLTypeUtil;
 import graphql.util.TraversalControl;
 import graphql.util.TraverserContext;
-import java.util.HashSet;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
 import java.util.stream.Collectors;
 import org.apache.commons.collections4.CollectionUtils;
-
-public class NoExternalReferenceSelectionSetModifier extends NodeVisitorStub {
+import org.apache.commons.collections4.MapUtils;
+
+/**
+ * This class modifies for query for a downstream provider.
+ *
+ * One function of this class is to remove external fields.  This occurs if a type
+ * is extended by other services and add fields to it.
+ *
+ * Another function is this class adds required fields to the query if fields
+ * are required by other sibling fields which are external or remote.
+ */
+public class DownstreamQueryModifier extends NodeVisitorStub {
 
   private final GraphQLFieldsContainer rootType;
   private final ServiceMetadata serviceMetadata;
   private final SelectionCollector selectionCollector;
 
-  NoExternalReferenceSelectionSetModifier(GraphQLFieldsContainer rootType,
+  DownstreamQueryModifier(
+      GraphQLFieldsContainer rootType,
       ServiceMetadata serviceMetadata,
       Map<String, FragmentDefinition> fragmentsByName) {
+    Objects.requireNonNull(rootType);
+    Objects.requireNonNull(serviceMetadata);
+    Objects.requireNonNull(fragmentsByName);
     this.rootType = rootType;
     this.serviceMetadata = serviceMetadata;
     this.selectionCollector = new SelectionCollector(fragmentsByName);
@@ -57,7 +73,12 @@ public TraversalControl visitField(Field node, TraverserContext<Node> context) {
       String fieldName = node.getName();
       GraphQLFieldDefinition fieldDefinition = getFieldDefinition(fieldName, parentType);
       requireNonNull(fieldDefinition, "Failed to get Field Definition for " + fieldName);
-      if (hasResolverDirective(fieldDefinition)) {
+
+      // TODO consider the entire condition to be abstracted in
+      //  serviceMetadata.isFieldExternal(fieldCoordinates).
+      //  This requires a complete set of field coordinates that the service owns
+      if (hasResolverDirective(fieldDefinition)
+          || isExternalField(parentType.getName(), fieldName)) {
         return deleteNode(context);
       }
 
@@ -69,15 +90,22 @@ public TraversalControl visitField(Field node, TraverserContext<Node> context) {
     }
   }
 
-  private GraphQLFieldDefinition getFieldDefinition(String name, GraphQLFieldsContainer parentType) {
+  private boolean isExternalField(String parentTypename, String fieldName) {
+    FieldCoordinates fieldCoordinates = coordinates(parentTypename, fieldName);
+    return serviceMetadata.isOwnedByEntityExtension(fieldCoordinates);
+  }
+
+  private GraphQLFieldDefinition getFieldDefinition(
+      String name, GraphQLFieldsContainer parentType) {
     if (TypeNameMetaFieldDef.getName().equals(name)) {
       return TypeNameMetaFieldDef;
     }
     return parentType.getFieldDefinition(name);
   }
 
   @Override
-  public TraversalControl visitFragmentDefinition(FragmentDefinition node, TraverserContext<Node> context) {
+  public TraversalControl visitFragmentDefinition(
+      FragmentDefinition node, TraverserContext<Node> context) {
     // if modifying selection set in a fragment definition, this will be the first code to visit.
     context.setVar(GraphQLType.class, rootType);
     return TraversalControl.CONTINUE;
@@ -102,19 +130,18 @@ public TraversalControl visitSelectionSet(SelectionSet node, TraverserContext<No
     context.setVar(GraphQLType.class, parentType);
     String parentTypeName = parentType.getName();
 
-    Map<String, Field> selectedFields = this.selectionCollector.collectFields(node);
-    Set<Field> fieldsToAdd = new HashSet<>();
-    getFieldsWithResolverDirective(parentTypeName, selectedFields)
-        .forEach(fieldResolverContext -> {
-          Set<String> fldResolverReqdFields = fieldResolverContext.getRequiredFields();
-          if (CollectionUtils.isNotEmpty(fldResolverReqdFields)) {
-            fieldsToAdd.addAll(
-                fldResolverReqdFields.stream()
-                .filter(s -> !selectedFields.containsKey(s))
-                .map(s -> Field.newField(s).build())
-                .collect(Collectors.toSet()));
-          }
-        });
+    Map<String, Field> selectedFields =  this.selectionCollector.collectFields(node);
+
+    RequiredFieldsCollector fedRequiredFieldsCollector = RequiredFieldsCollector
+        .builder()
+        .excludeFields(selectedFields)
+        .parentTypeName(parentTypeName)
+        .serviceMetadata(this.serviceMetadata)
+        .fieldResolverContexts(getFieldsWithResolverDirective(parentTypeName, selectedFields))
+        .fieldsWithRequiresDirective(getFieldsWithRequiresDirective(parentTypeName, selectedFields))
+        .build();
+
+    Set<Field> fieldsToAdd = fedRequiredFieldsCollector.get();
 
     if (CollectionUtils.isNotEmpty(fieldsToAdd)) {
       SelectionSet newNode = node.transform(builder -> {
@@ -129,7 +156,6 @@ public TraversalControl visitSelectionSet(SelectionSet node, TraverserContext<No
     return TraversalControl.CONTINUE;
   }
 
-
   private List<FieldResolverContext> getFieldsWithResolverDirective(
       String parentTypename,  Map<String, Field> selectedFields) {
     return selectedFields.values().stream()
@@ -142,9 +168,23 @@ private List<FieldResolverContext> getFieldsWithResolverDirective(
         .collect(Collectors.toList());
   }
 
-  private GraphQLType getParentType(@SuppressWarnings("rawtypes") TraverserContext<Node> context) {
+  private Set<Field> getFieldsWithRequiresDirective(String parentTypename,  Map<String, Field> selectedFields) {
+    if (MapUtils.isEmpty(selectedFields)) {
+      return Collections.emptySet();
+    }
+
+    FederationMetadata federationMetadata = this.serviceMetadata.getFederationServiceMetadata();
+    return selectedFields.values().stream()
+        .filter(field -> isExternalField(parentTypename, field.getName()))
+        .filter(field -> {
+          FieldCoordinates fieldCoordinates = coordinates(parentTypename, field.getName());
+          return federationMetadata.hasRequiresFieldSet(fieldCoordinates);
+        })
+        .collect(Collectors.toSet());
+  }
+
+  private GraphQLType getParentType(TraverserContext<Node> context) {
     GraphQLType parentType = context.getParentContext().getVar(GraphQLType.class);
     return GraphQLTypeUtil.unwrapAll(parentType);
   }
-
-}
+}

src/main/java/com/intuit/graphql/orchestrator/batch/FieldResolverBatchLoader.java

@@ -116,7 +116,7 @@ private OperationDefinition removeExternalFields(OperationDefinition operationDe
     GraphQLObjectType rootType = graphQLSchema.getQueryType();
     Map<String, FragmentDefinition> fragmentsByName = dataFetchingEnvironment.getFragmentsByName();
     return (OperationDefinition) AST_TRANSFORMER.transform(operationDefinition,
-        new NoExternalReferenceSelectionSetModifier((GraphQLFieldsContainer) unwrapAll(rootType), serviceMetadata, fragmentsByName));
+        new DownstreamQueryModifier((GraphQLFieldsContainer) unwrapAll(rootType), serviceMetadata, fragmentsByName));
   }
 
   private ServiceMetadata getServiceMetadata(DataFetchingEnvironment dataFetchingEnvironment) {

src/main/java/com/intuit/graphql/orchestrator/batch/GraphQLServiceBatchLoader.java

@@ -116,10 +116,9 @@ private CompletableFuture<List<DataFetcherResult<Object>>> load(List<DataFetchin
       MergedField filteredRootField = result.getMergedField();
       if (filteredRootField != null) {
         filteredRootField.getFields().stream()
-            .map(field -> serviceMetadata.hasFieldResolverDirective()
-                ? removeFieldsWithExternalTypes(field, getRootFieldDefinition(key.getExecutionStepInfo()).getType(), key.getFragmentsByName())
-                : field
-            )
+            .map(field -> (serviceMetadata.shouldRemoveExternalFields())
+                        ? removeFieldsWithExternalTypes(field, getRootFieldDefinition(key.getExecutionStepInfo()).getType(), key.getFragmentsByName())
+                        : field)
             .forEach(selectionSetBuilder::selection);
       }
 
@@ -142,7 +141,7 @@ private CompletableFuture<List<DataFetcherResult<Object>>> load(List<DataFetchin
 
       Map<String, FragmentDefinition> svcFragmentDefinitions = filterFragmentDefinitionByService(
           key.getFragmentsByName());
-      if (serviceMetadata.hasFieldResolverDirective()) {
+      if (serviceMetadata.hasFieldResolverDirective() || serviceMetadata.isFederationService()) {
         Map<String, FragmentDefinition> finalServiceFragmentDefinitions = new HashMap<>();
         svcFragmentDefinitions.forEach((fragmentName, fragmentDefinition) -> {
           String typeConditionName = fragmentDefinition.getTypeCondition().getName();
@@ -266,15 +265,15 @@ private CompletableFuture<Map<String, Object>> execute(GraphQLContext context, O
    *
    * @param origFragmentDefinition original fragment definition
    * @param typeCondition type condition of the original fragment definition.  This will be used as
-   *                      the root type for {@link NoExternalReferenceSelectionSetModifier}
+   *                      the root type for {@link DownstreamQueryModifier}
    * @return a modified fragment definition
    */
   private FragmentDefinition removeFieldsWithExternalTypes(final FragmentDefinition origFragmentDefinition,
       GraphQLType typeCondition, Map<String, FragmentDefinition> fragmentsByName) {
     // call serviceMetadata.hasFieldResolverDirective() before calling this method
     return (FragmentDefinition) AST_TRANSFORMER.transform(origFragmentDefinition,
-        new NoExternalReferenceSelectionSetModifier((GraphQLFieldsContainer) unwrapAll(typeCondition),
-            serviceMetadata, fragmentsByName));
+        new DownstreamQueryModifier((GraphQLFieldsContainer) unwrapAll(typeCondition), serviceMetadata, fragmentsByName));
+
   }
 
   /**
@@ -301,14 +300,13 @@ private FragmentDefinition removeDomainTypeFromFragment(final FragmentDefinition
    *
    * @param origField field to be processed.
    * @param fieldType the type of origField.  This will be used as the root type for {@link
-   * NoExternalReferenceSelectionSetModifier}
+   * DownstreamQueryModifier}
    * @return a modified field
    */
-  private Field removeFieldsWithExternalTypes(Field origField, GraphQLOutputType fieldType, Map<String,
-      FragmentDefinition> fragmentsByName) {
+  private Field removeFieldsWithExternalTypes(Field origField, GraphQLOutputType fieldType, Map<String, FragmentDefinition> fragmentsByName) {
     // call serviceMetadata.hasFieldResolverDirective() before calling this method
     return (Field) AST_TRANSFORMER.transform(origField,
-        new NoExternalReferenceSelectionSetModifier((GraphQLFieldsContainer) unwrapAll(fieldType), serviceMetadata, fragmentsByName));
+        new DownstreamQueryModifier((GraphQLFieldsContainer) unwrapAll(fieldType), serviceMetadata, fragmentsByName));
   }
 
   private GraphQLSchema getSchema(List<DataFetchingEnvironment> environments) {