feat: integrate extended GraphQL scalars

Author: BlasiusSecundus

README.md

@@ -16,7 +16,7 @@ and join the team!
 <!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
 **Table of Contents**
 
-- [WARNING: NoClassDefFoundError when using GraphQL Java Tools > 5.4.x](#warning-noclassdeffounderror-when-using-graphql-java-tools--54x)
+  - [WARNING: NoClassDefFoundError when using GraphQL Java Tools > 5.4.x](#warning-noclassdeffounderror-when-using-graphql-java-tools--54x)
     - [Using Gradle](#using-gradle)
     - [Using Maven](#using-maven)
 - [Documentation](#documentation)
@@ -26,21 +26,22 @@ and join the team!
 - [Enable Graph*i*QL](#enable-graphiql)
 - [Enable Altair](#enable-altair)
 - [Enable GraphQL Playground](#enable-graphql-playground)
-    - [Basic settings](#basic-settings)
-    - [CDN](#cdn)
-    - [Custom static resources](#custom-static-resources)
-    - [Customizing GraphQL Playground](#customizing-graphql-playground)
-    - [Tabs](#tabs)
+  - [Basic settings](#basic-settings)
+  - [CDN](#cdn)
+  - [Custom static resources](#custom-static-resources)
+  - [Customizing GraphQL Playground](#customizing-graphql-playground)
+  - [Tabs](#tabs)
 - [Supported GraphQL-Java Libraries](#supported-graphql-java-libraries)
-    - [GraphQL Java Tools](#graphql-java-tools)
-    - [GraphQL Annotations](#graphql-annotations)
-        - [Configuration](#configuration)
-        - [Root resolvers, directives, type extensions](#root-resolvers-directives-type-extensions)
-        - [Interfaces](#interfaces)
-        - [Custom scalars and type functions](#custom-scalars-and-type-functions)
-        - [Custom Relay and GraphQL Annotation Processor](#custom-relay-and-graphql-annotation-processor)
+  - [GraphQL Java Tools](#graphql-java-tools)
+  - [GraphQL Annotations](#graphql-annotations)
+    - [Configuration](#configuration)
+    - [Root resolvers, directives, type extensions](#root-resolvers-directives-type-extensions)
+    - [Interfaces](#interfaces)
+    - [Custom scalars and type functions](#custom-scalars-and-type-functions)
+    - [Custom Relay and GraphQL Annotation Processor](#custom-relay-and-graphql-annotation-processor)
+  - [Extended scalars](#extended-scalars)
 - [Tracing and Metrics](#tracing-and-metrics)
-    - [Usage](#usage)
+  - [Usage](#usage)
 - [Contributions](#contributions)
 - [Licenses](#licenses)
 
@@ -537,6 +538,31 @@ It is possible to define a bean implementing `Relay` and/or `GraphQLAnnotations`
 will be passed to the schema builder. Spring dependency injection works as usual. Note that GraphQL
 Annotations provides default implementation for these which should be sufficient is most cases.
 
+## Extended scalars
+
+[Extended scalars](https://github.com/graphql-java/graphql-java-extended-scalars) can be enabled by using the 
+`graphql.extended-scalars` configuration property, e. g.:
+
+```yaml
+graphql:
+  extended-scalars: BigDecimal, Date
+```
+
+The available scalars are the following: `BigDecimal`, `BigInteger`, `Byte`, `Char`, `Date`, `DateTime`, `JSON`, 
+`Locale`, `Long`, `NegativeFloat`, `NegativeInt`, `NonNegativeFloat`, `NonNegativeInt`, `NonPositiveFloat`, 
+`NonPositiveInt`, `Object`, `PositiveFloat`, `PositiveInt`, `Short`, `Time`, `Url`.
+
+This setting works with both the [GraphQL Java Tools](#graphql-java-tools) and the
+[GraphQL Annotations](#graphql-annotations) integration.
+
+When using the [GraphQL Java Tools](#graphql-java-tools) integration, the scalars must also be declared in the GraphQL 
+Schema:
+
+```graphql
+scalar BigDecimal
+scalar Date
+```
+
 # Tracing and Metrics
 
 [Apollo style tracing](https://github.com/apollographql/apollo-tracing) along with two levels of

example-graphql-subscription/src/main/resources/application.yml

@@ -3,3 +3,6 @@ spring:
     name: graphql-subscription-example
 server:
   port: 9001
+
+graphql:
+  extended-scalars: BigDecimal

example-graphql-subscription/src/main/resources/subscription.graphqls

@@ -6,6 +6,8 @@ schema {
     subscription : Subscription
 }
 
+scalar BigDecimal
+
 type Query {
     hello : String
 }
@@ -17,6 +19,6 @@ type Subscription {
 type StockPriceUpdate {
     dateTime : String
     stockCode : String
-    stockPrice : Float
-    stockPriceChange : Float!
+    stockPrice : BigDecimal
+    stockPriceChange : BigDecimal!
 }

gradle.properties

@@ -32,6 +32,7 @@ SOURCE_COMPATIBILITY=1.8
 TARGET_COMPATIBILITY=1.8
 ### Dependencies
 LIB_GRAPHQL_JAVA_VER=16.1
+LIB_EXTENDED_SCALARS_VERSION=15.0.0
 LIB_SPRING_BOOT_VER=2.4.2
 LIB_GRAPHQL_SERVLET_VER=11.0.0
 LIB_GRAPHQL_JAVA_TOOLS_VER=11.0.0

graphql-spring-boot-autoconfigure/build.gradle

@@ -21,6 +21,7 @@ dependencies {
     api(project(":graphql-kickstart-spring-boot-starter-tools"))
     api(project(":graphql-kickstart-spring-support"))
     implementation "org.springframework.boot:spring-boot-autoconfigure"
+    api "com.graphql-java:graphql-java-extended-scalars:$LIB_EXTENDED_SCALARS_VERSION"
     api "com.graphql-java-kickstart:graphql-java-kickstart:$LIB_GRAPHQL_SERVLET_VER"
     api "com.graphql-java-kickstart:graphql-java-servlet:$LIB_GRAPHQL_SERVLET_VER"
     api "com.graphql-java:graphql-java:$LIB_GRAPHQL_JAVA_VER"

graphql-spring-boot-autoconfigure/src/main/java/graphql/kickstart/spring/web/boot/GraphQLExtendedScalarsInitializer.java

@@ -0,0 +1,68 @@
+package graphql.kickstart.spring.web.boot;
+
+import graphql.scalars.ExtendedScalars;
+import graphql.schema.GraphQLScalarType;
+import lombok.NoArgsConstructor;
+import org.springframework.context.ApplicationContextException;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.support.GenericApplicationContext;
+import org.springframework.util.ReflectionUtils;
+
+import java.lang.reflect.Modifier;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+@NoArgsConstructor
+public class GraphQLExtendedScalarsInitializer implements ApplicationContextInitializer<GenericApplicationContext> {
+
+    @Override
+    public void initialize(final GenericApplicationContext applicationContext) {
+        final Collection<String> enabledExtendedScalars = getEnabledExtendedScalars(applicationContext);
+        final Collection<String> validScalarNames = new HashSet<>();
+        ReflectionUtils.doWithFields(ExtendedScalars.class, scalarField -> {
+            if (Modifier.isPublic(scalarField.getModifiers()) && Modifier.isStatic(scalarField.getModifiers())
+                && scalarField.getType().equals(GraphQLScalarType.class)) {
+                final GraphQLScalarType graphQLScalarType = (GraphQLScalarType) scalarField.get(null);
+                if (enabledExtendedScalars.contains(graphQLScalarType.getName())) {
+                    applicationContext.registerBean(
+                        graphQLScalarType.getName(),
+                        GraphQLScalarType.class,
+                        () -> graphQLScalarType
+                    );
+                }
+                validScalarNames.add(graphQLScalarType.getName());
+            }
+        });
+        verifyEnabledScalars(enabledExtendedScalars, validScalarNames);
+    }
+
+    private void verifyEnabledScalars(
+        final Collection<String> enabledExtendedScalars,
+        final Collection<String> validScalarNames
+    ) {
+        final Collection<String> invalidScalarNames = new HashSet<>(enabledExtendedScalars);
+        invalidScalarNames.removeAll(validScalarNames);
+        if (!invalidScalarNames.isEmpty()) {
+            throw new ApplicationContextException(String.format(
+                    "Invalid extended scalar name(s) found: %s. Valid names are: %s.",
+                    joinNames(invalidScalarNames),
+                    joinNames(validScalarNames)
+                )
+            );
+        }
+    }
+
+    private String joinNames(final Collection<String> names) {
+        return names.stream().sorted().collect(Collectors.joining(", "));
+    }
+
+    @SuppressWarnings("unchecked")
+    private Set<String> getEnabledExtendedScalars(final GenericApplicationContext applicationContext) {
+        return (Set<String>) applicationContext.getEnvironment()
+            .getProperty("graphql.extended-scalars", Collection.class, Collections.emptySet())
+            .stream().map(String::valueOf).collect(Collectors.toSet());
+    }
+}

graphql-spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -5,5 +5,10 @@
     }
   ],
   "properties": [
+    {
+      "name": "graphql.extended-scalars",
+      "type": "java.util.Set",
+      "description": "List of extended scalars to be used."
+    }
   ]
 }

graphql-spring-boot-autoconfigure/src/main/resources/META-INF/spring.factories

@@ -1,3 +1,5 @@
+org.springframework.context.ApplicationContextInitializer=\
+graphql.kickstart.spring.web.boot.GraphQLExtendedScalarsInitializer
 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
 graphql.kickstart.spring.web.boot.GraphQLWebAutoConfiguration,\
 graphql.kickstart.spring.web.boot.GraphQLWebsocketAutoConfiguration,\

graphql-spring-boot-autoconfigure/src/test/java/graphql/kickstart/spring/web/boot/test/extendedscalars/ExtendedScalarAutoConfigurationTest.java

@@ -0,0 +1,38 @@
+package graphql.kickstart.spring.web.boot.test.extendedscalars;
+
+import graphql.scalars.ExtendedScalars;
+import graphql.schema.GraphQLScalarType;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.ApplicationContext;
+import org.springframework.test.context.TestPropertySource;
+
+import java.util.AbstractMap;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(
+    webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,
+    classes = ExtendedScalarAutoConfigurationTest.ExtendedScalarsTestApplication.class
+)
+@TestPropertySource(properties = "graphql.extended-scalars=BigDecimal")
+@DisplayName("Testing extended scalars auto configuration")
+public class ExtendedScalarAutoConfigurationTest {
+
+    @Autowired
+    private ApplicationContext applicationContext;
+
+    @Test
+    @DisplayName("The extended scalars initializer should be properly picked up by Spring auto configuration.")
+    void testAutoConfiguration() {
+        assertThat(applicationContext.getBeansOfType(GraphQLScalarType.class))
+            .containsOnly(new AbstractMap.SimpleEntry<>("BigDecimal", ExtendedScalars.GraphQLBigDecimal));
+    }
+
+    @SpringBootApplication
+    public static class ExtendedScalarsTestApplication {
+    }
+}

graphql-spring-boot-autoconfigure/src/test/java/graphql/kickstart/spring/web/boot/test/extendedscalars/ExtendedScalarsTest.java

@@ -0,0 +1,75 @@
+package graphql.kickstart.spring.web.boot.test.extendedscalars;
+
+import graphql.kickstart.spring.web.boot.GraphQLExtendedScalarsInitializer;
+import graphql.scalars.ExtendedScalars;
+import graphql.schema.GraphQLScalarType;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.WebApplicationType;
+import org.springframework.context.ApplicationContextException;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.core.env.StandardEnvironment;
+
+import java.util.AbstractMap;
+import java.util.Collections;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+
+@DisplayName("Testing extended scalars configuration")
+public class ExtendedScalarsTest {
+
+    @Test
+    @DisplayName("Should throw exception at context initialization when invalid extended scalar name is provided.")
+    void shouldThrowErrorOnStartupIfExtendedScalarDoesNotExists() {
+        // GIVEN
+        final SpringApplication application = setupTestApplication("Long,Short,Datee,BadDecimal");
+        // THEN
+        assertThatExceptionOfType(ApplicationContextException.class)
+            .isThrownBy(application::run)
+            .withMessage("Invalid extended scalar name(s) found: BadDecimal, Datee. Valid names are: BigDecimal, " +
+                "BigInteger, Byte, Char, Date, DateTime, JSON, Locale, Long, NegativeFloat, NegativeInt, " +
+                "NonNegativeFloat, NonNegativeInt, NonPositiveFloat, NonPositiveInt, Object, PositiveFloat, " +
+                "PositiveInt, Short, Time, Url.");
+    }
+
+    @Test
+    @DisplayName("Should not create any extended scalars by default.")
+    void shouldNotDeclareAnyExtendedScalarsByDefault() {
+        // GIVEN
+        final SpringApplication application = setupTestApplication(null);
+        // WHEN
+        final ConfigurableApplicationContext context = application.run();
+        // THEN
+        assertThat(context.getBeansOfType(GraphQLScalarType.class)).isEmpty();
+    }
+
+    @Test
+    @DisplayName("Should declare the configured extended scalars.")
+    void shouldDeclareTheConfiguredScalars() {
+        // GIVEN
+        final SpringApplication application = setupTestApplication("Long,Short,BigDecimal,Date");
+        // WHEN
+        final ConfigurableApplicationContext context = application.run();
+        // THEN
+        assertThat(context.getBeansOfType(GraphQLScalarType.class))
+            .containsOnly(
+                new AbstractMap.SimpleEntry<>("Long", ExtendedScalars.GraphQLLong),
+                new AbstractMap.SimpleEntry<>("Short", ExtendedScalars.GraphQLShort),
+                new AbstractMap.SimpleEntry<>("BigDecimal", ExtendedScalars.GraphQLBigDecimal),
+                new AbstractMap.SimpleEntry<>("Date", ExtendedScalars.Date)
+            );
+    }
+
+    private SpringApplication setupTestApplication(final String extendedScalarValue) {
+        final StandardEnvironment standardEnvironment = new StandardEnvironment();
+        standardEnvironment.getPropertySources().addFirst(new MapPropertySource("testProperties",
+            Collections.singletonMap("graphql.extended-scalars", extendedScalarValue)));
+        final SpringApplication application = new SpringApplication(GraphQLExtendedScalarsInitializer.class);
+        application.setWebApplicationType(WebApplicationType.NONE);
+        application.setEnvironment(standardEnvironment);
+        return application;
+    }
+}