BAEL-5308 An Introduction to Domain Graph Service (DGS) Framework (#11718)

Co-authored-by: Adrianna Zychewicz <adrianna.zychewicz@decerto.pl>

graphql/graphql-dgs/pom.xml

@@ -0,0 +1,91 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung.graphql-dgs</groupId>
+    <artifactId>graphql-dgs</artifactId>
+    <version>1.0</version>
+    <name>graphql-dgs</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../..</relativePath>
+    </parent>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>com.netflix.graphql.dgs</groupId>
+                <artifactId>graphql-dgs-platform-dependencies</artifactId>
+                <version>4.1.0</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+            <version>2.6.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <version>2.6.2</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.netflix.graphql.dgs.codegen</groupId>
+            <artifactId>graphql-dgs-codegen-client-core</artifactId>
+            <version>5.1.14</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>2.6.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.netflix.graphql.dgs</groupId>
+            <artifactId>graphql-dgs-spring-boot-starter</artifactId>
+            <version>4.9.15</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+                <version>2.6.2</version>
+            </plugin>
+            <plugin>
+                <groupId>io.github.deweyjose</groupId>
+                <artifactId>graphqlcodegen-maven-plugin</artifactId>
+                <version>1.14</version>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>generate</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <schemaPaths>
+                        <param>src/main/resources/schema/schema.graphqls</param>
+                    </schemaPaths>
+                    <packageName>com.bealdung.graphqldgs.generated</packageName>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

graphql/graphql-dgs/src/main/java/com/bealdung/graphqlDGS/Album.java

@@ -0,0 +1,25 @@
+package com.bealdung.graphqlDGS;
+
+public class Album {
+    private final String title;
+    private final String artist;
+    private final Integer recordNo;
+
+    public Album(String title, String artist, Integer recordNo) {
+        this.title = title;
+        this.recordNo = recordNo;
+        this.artist = artist;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getArtist() {
+        return artist;
+    }
+
+    public Integer getRecordNo() {
+        return recordNo;
+    }
+}

graphql/graphql-dgs/src/main/java/com/bealdung/graphqlDGS/AlbumsDataFetcher.java

@@ -0,0 +1,28 @@
+package com.bealdung.graphqlDGS;
+
+import com.netflix.graphql.dgs.DgsComponent;
+import com.netflix.graphql.dgs.DgsQuery;
+import com.netflix.graphql.dgs.InputArgument;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+@DgsComponent
+public class AlbumsDataFetcher {
+
+    private final List<Album> albums = Arrays.asList(
+      new Album("Rumours", "Fleetwood Mac", 20),
+      new Album("What's Going On", "Marvin Gaye", 10),
+      new Album("Pet Sounds", "The Beach Boys", 12)
+    );
+
+    @DgsQuery
+    public List<Album> albums(@InputArgument String titleFilter) {
+        if(titleFilter == null) {
+            return albums;
+        }
+        return albums.stream()
+                .filter(s -> s.getTitle().contains(titleFilter))
+                .collect(Collectors.toList());
+    }
+}

graphql/graphql-dgs/src/main/java/com/bealdung/graphqlDGS/Application.java

@@ -0,0 +1,13 @@
+package com.bealdung.graphqlDGS;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+
+}

graphql/graphql-dgs/src/main/resources/application.properties

@@ -0,0 +1 @@
+server.servlet.context-path=

graphql/graphql-dgs/src/main/resources/schema/schema.graphqls

@@ -0,0 +1,9 @@
+type Query {
+    albums(titleFilter: String): [Album]
+}
+
+type Album {
+    title: String
+    artist: String
+    recordNo: Int
+}

pom.xml

@@ -422,6 +422,7 @@
                 <!-- <module>gradle-6</module> --> <!-- Not a maven project -->
                 <!-- <module>grails</module> --> <!-- Not a maven project -->
                 <module>graphql/graphql-java</module>
+                <module>graphql/graphql-dgs</module>
                 <module>grpc</module>
                 <module>gson</module>
                 <module>guava-modules</module>