Ability to combine multiple response projections #985

Author: kobylynskyi

src/main/java/com/kobylynskyi/graphql/codegen/model/graphql/GraphQLParametrizedInput.java

@@ -5,4 +5,6 @@
  */
 public interface GraphQLParametrizedInput {
 
+    GraphQLParametrizedInput deepCopy();
+
 }

src/main/java/com/kobylynskyi/graphql/codegen/model/graphql/GraphQLResponseField.java

@@ -86,4 +86,18 @@ public boolean equals(Object obj) {
     public int hashCode() {
         return Objects.hash(name, alias, parameters, projection);
     }
+
+    public GraphQLResponseField deepCopy() {
+        GraphQLResponseField deepCopy = new GraphQLResponseField(this.name);
+        if (this.alias != null) {
+            deepCopy.alias = this.alias;
+        }
+        if (this.parameters != null) {
+            deepCopy.parameters = this.parameters.deepCopy();
+        }
+        if (this.projection != null) {
+            deepCopy.projection = this.projection.deepCopy$();
+        }
+        return deepCopy;
+    }
 }

src/main/java/com/kobylynskyi/graphql/codegen/model/graphql/GraphQLResponseProjection.java

@@ -1,24 +1,75 @@
 package com.kobylynskyi.graphql.codegen.model.graphql;
 
-import java.util.ArrayList;
+import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.StringJoiner;
 
 /**
- * The implementation class should basically contain the fields of the particular type which
- * should be returned back to the client.
+ * The implementation class should contain the fields of the particular type that should be returned to the client.
  */
 public abstract class GraphQLResponseProjection {
 
-    protected final List<GraphQLResponseField> fields = new ArrayList<>();
+    protected final Map<String, GraphQLResponseField> fields = new LinkedHashMap<>();
+
+    public GraphQLResponseProjection() {
+    }
+
+    public GraphQLResponseProjection(GraphQLResponseProjection projection) {
+        if (projection == null) {
+            return;
+        }
+        projection.fields.values().forEach(this::add$);
+    }
+
+    public GraphQLResponseProjection(List<? extends GraphQLResponseProjection> projections) {
+        if (projections == null) {
+            return;
+        }
+        for (GraphQLResponseProjection projection : projections) {
+            if (projection == null) {
+                continue;
+            }
+            projection.fields.values().forEach(this::add$);
+        }
+    }
+
+    public abstract GraphQLResponseProjection deepCopy$();
+
+    protected void add$(GraphQLResponseField responseField) {
+        GraphQLResponseField existingResponseField = fields.get(responseField.getName());
+        if (existingResponseField != null) {
+            if (responseField.getAlias() != null) {
+                existingResponseField.alias(responseField.getAlias());
+            }
+            if (responseField.getParameters() != null) {
+                existingResponseField.parameters(responseField.getParameters().deepCopy());
+            }
+            if (responseField.getProjection() != null) {
+                GraphQLResponseProjection projectionCopy = responseField.getProjection().deepCopy$();
+                if (existingResponseField.getProjection() != null) {
+                    for (GraphQLResponseField field : projectionCopy.fields.values()) {
+                        existingResponseField.getProjection().add$(field);
+                    }
+                } else {
+                    existingResponseField.projection(projectionCopy);
+                }
+            }
+        } else {
+            fields.put(responseField.getName(), responseField.deepCopy());
+        }
+    }
 
     @Override
     public String toString() {
         if (fields.isEmpty()) {
             return "";
         }
         StringJoiner joiner = new StringJoiner(" ", "{ ", " }");
-        fields.forEach(field -> joiner.add(field.toString()));
+        for (GraphQLResponseField value : fields.values()) {
+            joiner.add(value.toString());
+        }
         return joiner.toString();
     }
+
 }

src/main/resources/templates/java-lang/parametrized_input.ftl

@@ -70,6 +70,17 @@ public class ${className} implements GraphQLParametrizedInput {
 
 </#list>
 </#if>
+    @Override
+    public ${className} deepCopy() {
+        ${className} parametrizedInput = new ${className}();
+        <#if fields?has_content>
+        <#list fields as field>
+        parametrizedInput.${field.name}(this.${field.name});
+        </#list>
+        </#if>
+        return parametrizedInput;
+    }
+
 <#if equalsAndHashCode>
     @Override
     public boolean equals(Object obj) {

src/main/resources/templates/java-lang/response_projection.ftl

@@ -8,6 +8,7 @@ import com.kobylynskyi.graphql.codegen.model.graphql.GraphQLResponseProjection;
 import java.util.HashMap;
 import java.util.Map;
 </#if>
+import java.util.List;
 <#if equalsAndHashCode>
 import java.util.Objects;
 </#if>
@@ -36,6 +37,14 @@ public class ${className} extends GraphQLResponseProjection {
 
     public ${className}() {
     }
+
+    public ${className}(${className} projection) {
+        super(projection);
+    }
+
+    public ${className}(List<${className}> projections) {
+        super(projections);
+    }
 <#if fields?has_content && generateAllMethodInProjection>
 
     public ${className} all$() {
@@ -76,7 +85,7 @@ public class ${className} extends GraphQLResponseProjection {
     }
 
     public ${className} ${field.methodName}(String alias<#if field.type?has_content>, ${field.type} subProjection</#if>) {
-        fields.add(new GraphQLResponseField("${field.name}").alias(alias)<#if field.type?has_content>.projection(subProjection)</#if>);
+        add$(new GraphQLResponseField("${field.name}").alias(alias)<#if field.type?has_content>.projection(subProjection)</#if>);
         return this;
     }
 
@@ -86,13 +95,18 @@ public class ${className} extends GraphQLResponseProjection {
     }
 
     public ${className} ${field.methodName}(String alias, ${field.parametrizedInputClassName} input<#if field.type?has_content>, ${field.type} subProjection</#if>) {
-        fields.add(new GraphQLResponseField("${field.name}").alias(alias).parameters(input)<#if field.type?has_content>.projection(subProjection)</#if>);
+        add$(new GraphQLResponseField("${field.name}").alias(alias).parameters(input)<#if field.type?has_content>.projection(subProjection)</#if>);
         return this;
     }
 
 </#if>
 </#list>
 </#if>
+    @Override
+    public ${className} deepCopy$() {
+        return new ${className}(this);
+    }
+
 <#if equalsAndHashCode>
     @Override
     public boolean equals(Object obj) {

src/test/java/com/kobylynskyi/graphql/codegen/TestUtils.java

@@ -7,6 +7,10 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.OpenOption;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
 import java.time.ZonedDateTime;
 import java.util.Arrays;
 

src/test/java/com/kobylynskyi/graphql/codegen/model/graphql/GraphQLResponseProjectionTest.java

@@ -0,0 +1,98 @@
+package com.kobylynskyi.graphql.codegen.model.graphql;
+
+import com.kobylynskyi.graphql.codegen.model.graphql.data.EventPropertyChildParametrizedInput;
+import com.kobylynskyi.graphql.codegen.model.graphql.data.EventPropertyResponseProjection;
+import com.kobylynskyi.graphql.codegen.model.graphql.data.EventResponseProjection;
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class GraphQLResponseProjectionTest {
+
+    @Test
+    public void deepCopy_empty() {
+        EventResponseProjection original = new EventResponseProjection();
+
+        EventResponseProjection deepCopy = original.deepCopy$();
+
+        assertTrue(deepCopy.fields.isEmpty());
+    }
+
+    @Test
+    public void deepCopy() {
+        EventResponseProjection original = new EventResponseProjection();
+        original.id();
+        original.status("state");
+        original.properties(new EventPropertyResponseProjection()
+                .intVal()
+                .stringVal()
+                .child(new EventPropertyChildParametrizedInput(1, 2),
+                        new EventPropertyResponseProjection()
+                                .booleanVal()));
+
+        EventResponseProjection deepCopy = original.deepCopy$();
+
+        assertEquals("{ id state : status properties { intVal stringVal child (first: 1, last: 2) { booleanVal } } }",
+                original.toString());
+        assertEquals("{ id state : status properties { intVal stringVal child (first: 1, last: 2) { booleanVal } } }",
+                deepCopy.toString());
+
+        original.active();
+        deepCopy.rating();
+
+        assertEquals("{ id state : status properties { intVal stringVal child (first: 1, last: 2) { booleanVal } } active }",
+                original.toString());
+        assertEquals("{ id state : status properties { intVal stringVal child (first: 1, last: 2) { booleanVal } } rating }",
+                deepCopy.toString());
+    }
+
+    @Test
+    public void join() {
+        EventResponseProjection projection1 = new EventResponseProjection();
+        projection1.id();
+        projection1.status("state");
+        projection1.properties(new EventPropertyResponseProjection()
+                .intVal()
+                .stringVal()
+                .child(new EventPropertyChildParametrizedInput(1, 2),
+                        new EventPropertyResponseProjection()
+                                .booleanVal()));
+
+        EventResponseProjection projection2 = new EventResponseProjection();
+        projection2.id("uid");
+        projection2.active();
+        projection2.properties(new EventPropertyResponseProjection()
+                .floatVal()
+                .child(new EventPropertyChildParametrizedInput(3, 4),
+                        new EventPropertyResponseProjection()
+                                .intVal()));
+
+        EventResponseProjection projection12 = new EventResponseProjection(Arrays.asList(projection1, projection2));
+        assertEquals("{ uid : id state : status properties { intVal stringVal child (first: 3, last: 4) { booleanVal intVal } floatVal } active }",
+                projection12.toString());
+    }
+
+    @Test
+    public void join_safe() {
+        EventResponseProjection projection1 = new EventResponseProjection();
+        projection1.id(null);
+        projection1.properties(null);
+
+        EventResponseProjection projection2 = new EventResponseProjection();
+        projection2.properties(new EventPropertyResponseProjection()
+                .child(null));
+
+        EventResponseProjection projection3 = new EventResponseProjection();
+        projection2.properties(new EventPropertyResponseProjection()
+                .child(null, null, new EventPropertyResponseProjection()
+                        .child(null)));
+
+        EventResponseProjection projection123 = new EventResponseProjection(Arrays.asList(projection1, projection2, projection3));
+        assertEquals("{ id properties { child { child } } }",
+                projection123.toString());
+    }
+
+}

src/test/java/com/kobylynskyi/graphql/codegen/model/graphql/data/EventPropertyChildParametrizedInput.java

@@ -62,4 +62,11 @@ public String toString() {
         return joiner.toString();
     }
 
+    @Override
+    public EventPropertyChildParametrizedInput deepCopy() {
+        EventPropertyChildParametrizedInput parametrizedInput = new EventPropertyChildParametrizedInput();
+        parametrizedInput.first(this.first);
+        parametrizedInput.last(this.last);
+        return parametrizedInput;
+    }
 }

src/test/java/com/kobylynskyi/graphql/codegen/model/graphql/data/EventPropertyParentParametrizedInput.java

@@ -62,4 +62,11 @@ public String toString() {
         return joiner.toString();
     }
 
+    @Override
+    public EventPropertyParentParametrizedInput deepCopy() {
+        EventPropertyParentParametrizedInput parametrizedInput = new EventPropertyParentParametrizedInput();
+        parametrizedInput.withStatus(this.withStatus);
+        parametrizedInput.createdAfter(this.createdAfter);
+        return parametrizedInput;
+    }
 }