Validators for JSON and Graphql Exporter

elide-async/src/main/java/com/yahoo/elide/async/export/validator/NoRelationshipsProjectionValidator.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2021, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.async.export.validator;
+
+import com.yahoo.elide.core.exceptions.BadRequestException;
+import com.yahoo.elide.core.request.EntityProjection;
+
+import java.util.Collection;
+
+/**
+ * Validates none of the projections have relationships.
+ */
+public class NoRelationshipsProjectionValidator implements Validator {
+
+    @Override
+    public void validateProjection(Collection<EntityProjection> projections) {
+        for (EntityProjection projection : projections) {
+            if (!projection.getRelationships().isEmpty()) {
+                throw new BadRequestException(
+                                "Export is not supported for Query that requires traversing Relationships.");
+            }
+        }
+    }
+}

elide-async/src/main/java/com/yahoo/elide/async/export/validator/SingleRootProjectionValidator.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2021, Yahoo Inc.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.async.export.validator;
+
+import com.yahoo.elide.core.exceptions.BadRequestException;
+import com.yahoo.elide.core.request.EntityProjection;
+
+import java.util.Collection;
+
+/**
+ * Validates each projection in collection have one projection only.
+ */
+public class SingleRootProjectionValidator implements Validator {
+
+    @Override
+    public void validateProjection(Collection<EntityProjection> projections) {
+        if (projections.size() != 1) {
+            throw new BadRequestException("Export is only supported for single Query with one root projection.");
+        }
+    }
+}

elide-async/src/main/java/com/yahoo/elide/async/export/validator/Validator.java

@@ -5,7 +5,9 @@
  */
 package com.yahoo.elide.async.export.validator;
 
-import graphql.language.Field;
+import com.yahoo.elide.core.request.EntityProjection;
+
+import java.util.Collection;
 
 /**
  * Utility interface used to validate Entity Projections.
@@ -14,8 +16,7 @@ public interface Validator {
 
     /**
      * Validates the EntityProjection.
-     * @param entityType Class of the Entity to be validated.
-     * @param field GraphQL Field.
+     * @param projections Collection of EntityProjections to validate.
      */
-    public void validateProjection(Class<?> entityType, Field field);
+    public void validateProjection(Collection<EntityProjection> projections);
 }

elide-async/src/main/java/com/yahoo/elide/async/operation/GraphQLTableExportOperation.java

@@ -7,13 +7,13 @@
 
 import com.yahoo.elide.Elide;
 import com.yahoo.elide.async.export.formatter.TableExportFormatter;
+import com.yahoo.elide.async.export.validator.NoRelationshipsProjectionValidator;
 import com.yahoo.elide.async.models.AsyncAPI;
 import com.yahoo.elide.async.models.TableExport;
 import com.yahoo.elide.async.service.AsyncExecutorService;
 import com.yahoo.elide.async.service.storageengine.ResultStorageEngine;
 import com.yahoo.elide.core.RequestScope;
 import com.yahoo.elide.core.datastore.DataStoreTransaction;
-import com.yahoo.elide.core.exceptions.BadRequestException;
 import com.yahoo.elide.core.request.EntityProjection;
 import com.yahoo.elide.core.security.User;
 import com.yahoo.elide.graphql.GraphQLRequestScope;
@@ -27,10 +27,10 @@
 import lombok.extern.slf4j.Slf4j;
 
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Optional;
 import java.util.UUID;
 
 /**
@@ -41,7 +41,8 @@ public class GraphQLTableExportOperation extends TableExportOperation {
 
     public GraphQLTableExportOperation(TableExportFormatter formatter, AsyncExecutorService service,
             AsyncAPI export, RequestScope scope, ResultStorageEngine engine) {
-        super(formatter, service, export, scope, engine);
+        super(formatter, service, export, scope, engine,
+                        Arrays.asList(new NoRelationshipsProjectionValidator()));
     }
 
     @Override
@@ -53,9 +54,8 @@ public RequestScope getRequestScope(TableExport export, User user, String apiVer
     }
 
     @Override
-    public EntityProjection getProjection(TableExport export, RequestScope scope)
-            throws BadRequestException {
-        EntityProjection projection;
+    public Collection<EntityProjection> getProjections(TableExport export, RequestScope scope) {
+        GraphQLProjectionInfo projectionInfo;
         try {
             String graphQLDocument = export.getQuery();
             Elide elide = getService().getElide();
@@ -65,20 +65,13 @@ public EntityProjection getProjection(TableExport export, RequestScope scope)
             Map<String, Object> variables = QueryRunner.extractVariables(mapper, node);
             String queryString = QueryRunner.extractQuery(node);
 
-            GraphQLProjectionInfo projectionInfo =
-                    new GraphQLEntityProjectionMaker(elide.getElideSettings(), variables, scope.getApiVersion())
-                        .make(queryString);
-
-            //TODO Call Validators.
-            Optional<Entry<String, EntityProjection>> optionalEntry =
-                    projectionInfo.getProjections().entrySet().stream().findFirst();
-
-            projection = optionalEntry.isPresent() ? optionalEntry.get().getValue() : null;
+            projectionInfo = new GraphQLEntityProjectionMaker(elide.getElideSettings(), variables,
+                            scope.getApiVersion()).make(queryString);
 
         } catch (IOException e) {
             throw new IllegalStateException(e);
         }
 
-        return projection;
+        return projectionInfo.getProjections().values();
     }
 }

elide-async/src/main/java/com/yahoo/elide/async/operation/JSONAPITableExportOperation.java

@@ -7,6 +7,7 @@
 
 import com.yahoo.elide.Elide;
 import com.yahoo.elide.async.export.formatter.TableExportFormatter;
+import com.yahoo.elide.async.export.validator.NoRelationshipsProjectionValidator;
 import com.yahoo.elide.async.models.AsyncAPI;
 import com.yahoo.elide.async.models.TableExport;
 import com.yahoo.elide.async.service.AsyncExecutorService;
@@ -22,6 +23,8 @@
 import lombok.extern.slf4j.Slf4j;
 
 import java.net.URISyntaxException;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.UUID;
 
@@ -35,7 +38,8 @@ public class JSONAPITableExportOperation extends TableExportOperation {
 
     public JSONAPITableExportOperation(TableExportFormatter formatter, AsyncExecutorService service,
             AsyncAPI export, RequestScope scope, ResultStorageEngine engine) {
-        super(formatter, service, export, scope, engine);
+        super(formatter, service, export, scope, engine,
+                        Arrays.asList(new NoRelationshipsProjectionValidator()));
     }
 
     @Override
@@ -53,7 +57,7 @@ public RequestScope getRequestScope(TableExport export, User user, String apiVer
     }
 
     @Override
-    public EntityProjection getProjection(TableExport export, RequestScope scope) throws BadRequestException {
+    public Collection<EntityProjection> getProjections(TableExport export, RequestScope scope) {
         EntityProjection projection = null;
         try {
             URIBuilder uri = new URIBuilder(export.getQuery());
@@ -64,6 +68,6 @@ public EntityProjection getProjection(TableExport export, RequestScope scope) th
         } catch (URISyntaxException e) {
             throw new BadRequestException(e.getMessage());
         }
-        return projection;
+        return Collections.singletonList(projection);
     }
 }

elide-async/src/main/java/com/yahoo/elide/async/operation/TableExportOperation.java

@@ -7,6 +7,8 @@
 
 import com.yahoo.elide.Elide;
 import com.yahoo.elide.async.export.formatter.TableExportFormatter;
+import com.yahoo.elide.async.export.validator.SingleRootProjectionValidator;
+import com.yahoo.elide.async.export.validator.Validator;
 import com.yahoo.elide.async.models.AsyncAPI;
 import com.yahoo.elide.async.models.AsyncAPIResult;
 import com.yahoo.elide.async.models.TableExport;
@@ -28,8 +30,12 @@
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.Date;
+import java.util.List;
 import java.util.UUID;
 
 import java.util.concurrent.Callable;
@@ -45,14 +51,16 @@ public abstract class TableExportOperation implements Callable<AsyncAPIResult> {
     private TableExport exportObj;
     private RequestScope scope;
     private ResultStorageEngine engine;
+    private List<Validator> validators = new ArrayList<>(Arrays.asList(new SingleRootProjectionValidator()));
 
     public TableExportOperation(TableExportFormatter formatter, AsyncExecutorService service,
-            AsyncAPI exportObj, RequestScope scope, ResultStorageEngine engine) {
+            AsyncAPI exportObj, RequestScope scope, ResultStorageEngine engine, List<Validator> validators) {
         this.formatter = formatter;
         this.service = service;
         this.exportObj = (TableExport) exportObj;
         this.scope = scope;
         this.engine = engine;
+        this.validators.addAll(validators);
     }
 
     @Override
@@ -64,7 +72,9 @@ public AsyncAPIResult call() {
         try (DataStoreTransaction tx = elide.getDataStore().beginTransaction()) {
 
             RequestScope requestScope = getRequestScope(exportObj, scope.getUser(), apiVersion, tx);
-            EntityProjection projection = getProjection(exportObj, requestScope);
+            Collection<EntityProjection> projections = getProjections(exportObj, requestScope);
+            validateProjections(projections);
+            EntityProjection projection = projections.iterator().next();
 
             Observable<PersistentResource> observableResults = export(exportObj, requestScope, projection);
 
@@ -85,7 +95,7 @@ public AsyncAPIResult call() {
             exportResult.setUrl(new URL(generateDownloadURL(exportObj, (RequestScope) scope)));
             exportResult.setRecordCount(recordNumber);
         } catch (BadRequestException e) {
-            exportResult.setMessage("Bad Request body");
+            exportResult.setMessage(e.getMessage());
         } catch (MalformedURLException e) {
             exportResult.setMessage("Download url generation failure.");
         }  catch (Exception e) {
@@ -194,14 +204,16 @@ protected TableExport storeResults(TableExport exportObj, ResultStorageEngine re
         return resultStorageEngine.storeResults(exportObj, result);
     }
 
+    private void validateProjections(Collection<EntityProjection> projections) {
+        validators.forEach(validator -> validator.validateProjection(projections));
+    }
+
     /**
      * Generate Entity Projection from the query.
      * @param exportObj TableExport type object.
      * @param requestScope requestScope object.
-     * @return EntityProjection object.
-     * @throws BadRequestException BadRequestException.
+     * @return Collection of EntityProjection object.
      */
-    public abstract EntityProjection getProjection(TableExport exportObj, RequestScope requestScope)
-            throws BadRequestException;
+    public abstract Collection<EntityProjection> getProjections(TableExport exportObj, RequestScope requestScope);
 
 }

elide-async/src/test/java/com/yahoo/elide/async/models/ArtifactGroup.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2021, Verizon Media.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.async.models;
+
+import com.yahoo.elide.annotation.Include;
+
+import java.util.ArrayList;
+import java.util.List;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+
+@Include(rootLevel = true, type = "group")
+@Entity
+public class ArtifactGroup {
+    @Id
+    private String name = "";
+
+    @OneToMany(mappedBy = "group")
+    private List<ArtifactProduct> products = new ArrayList<>();
+}

elide-async/src/test/java/com/yahoo/elide/async/models/ArtifactProduct.java

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2021, Verizon Media.
+ * Licensed under the Apache License, Version 2.0
+ * See LICENSE file in project root for terms.
+ */
+package com.yahoo.elide.async.models;
+
+import com.yahoo.elide.annotation.Include;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+@Include(type = "product")
+@Entity
+public class ArtifactProduct {
+    @Id
+    private String name = "";
+
+    @ManyToOne
+    private ArtifactGroup group = null;
+}