Backport federation to 1.9.x

docs/federation.md

@@ -0,0 +1,60 @@
+# Federation
+
+To enable support for [GraphQL Federation](https://www.apollographql.com/docs/federation), simply set the `smallrye.graphql.federation.enabled` config key to `true`.
+
+You can add the Federation directives by using the equivalent Java annotation, e.g. to extend a `Product` entity with a `price` field, you can write a class:
+
+```java
+package org.example.price;
+
+import org.eclipse.microprofile.graphql.Id;
+
+import io.smallrye.graphql.api.federation.Extends;
+import io.smallrye.graphql.api.federation.Key;
+
+@Extends @Key(fields = "id")
+public class Product {
+ @Id
+ private String id;
+
+ @Description("The price in cent")
+ private Integer price;
+
+ // getters and setters omitted
+}
+```
+
+And a normal query method that takes the `key` fields as a parameter and returns the requested type:
+
+```java
+package org.example.price;
+
+import org.eclipse.microprofile.graphql.GraphQLApi;
+import org.eclipse.microprofile.graphql.Id;
+import org.eclipse.microprofile.graphql.Query;
+
+@GraphQLApi
+public class Prices {
+ @Query
+ public Product product(@Id String id) {
+ return ...;
+ }
+}
+```
+
+The GraphQL Schema then contains:
+
+```graphql
+type Product @extends @key(fields : ["id"]) {
+ id: ID
+ price: Int
+}
+
+union _Entity = Product
+
+type Query {
+ _entities(representations: [_Any!]!): [_Entity]!
+ _service: _Service!
+ product(id: ID): Product
+}
+```

mkdocs.yml

@@ -7,6 +7,7 @@ nav:
  - Server side features:
  - Customizing JSON deserializers: 'custom-json-deserializers.md'
  - Directives: 'directives.md'
+ - Federation: 'federation.md'
  - Custom error extensions: 'custom-error-extensions.md'
  - Typesafe client:
  - Basic usage: 'typesafe-client-usage.md'

pom.xml

@@ -33,6 +33,7 @@
  <version.jakarta-validation>2.0.2</version.jakarta-validation>
  <version.jakarta-annotation>1.3.5</version.jakarta-annotation>
  <version.graphql-java>19.2</version.graphql-java>
+ <version.graphql-java-federation>2.0.8</version.graphql-java-federation>
  <verison.io.micrometer>1.9.3</verison.io.micrometer>
  <version.vertx>4.3.3</version.vertx>
 
@@ -231,6 +232,11 @@
  <artifactId>graphql-java</artifactId>
  <version>${version.graphql-java}</version>
  </dependency>
+ <dependency>
+ <groupId>com.apollographql.federation</groupId>
+ <artifactId>federation-graphql-java-support</artifactId>
+ <version>${version.graphql-java-federation}</version>
+ </dependency>
 
  <dependency>
  <groupId>io.vertx</groupId>

server/federation/api/src/main/java/io/smallrye/graphql/federation/api/Extends.java → server/api/src/main/java/io/smallrye/graphql/api/federation/Extends.java

@@ -1,4 +1,4 @@
-package io.smallrye.graphql.federation.api;
+package io.smallrye.graphql.api.federation;
 
 import static io.smallrye.graphql.api.DirectiveLocation.INTERFACE;
 import static io.smallrye.graphql.api.DirectiveLocation.OBJECT;

server/federation/api/src/main/java/io/smallrye/graphql/federation/api/External.java → server/api/src/main/java/io/smallrye/graphql/api/federation/External.java

@@ -1,4 +1,4 @@
-package io.smallrye.graphql.federation.api;
+package io.smallrye.graphql.api.federation;
 
 import static io.smallrye.graphql.api.DirectiveLocation.FIELD_DEFINITION;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;

server/federation/api/src/main/java/io/smallrye/graphql/federation/api/Key.java → server/api/src/main/java/io/smallrye/graphql/api/federation/Key.java

@@ -1,4 +1,4 @@
-package io.smallrye.graphql.federation.api;
+package io.smallrye.graphql.api.federation;
 
 import static io.smallrye.graphql.api.DirectiveLocation.INTERFACE;
 import static io.smallrye.graphql.api.DirectiveLocation.OBJECT;

server/federation/api/src/main/java/io/smallrye/graphql/federation/api/Provides.java → server/api/src/main/java/io/smallrye/graphql/api/federation/Provides.java

@@ -1,4 +1,4 @@
-package io.smallrye.graphql.federation.api;
+package io.smallrye.graphql.api.federation;
 
 import static io.smallrye.graphql.api.DirectiveLocation.FIELD_DEFINITION;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;

server/federation/api/src/main/java/io/smallrye/graphql/federation/api/Requires.java → server/api/src/main/java/io/smallrye/graphql/api/federation/Requires.java

@@ -1,4 +1,4 @@
-package io.smallrye.graphql.federation.api;
+package io.smallrye.graphql.api.federation;
 
 import static io.smallrye.graphql.api.DirectiveLocation.FIELD_DEFINITION;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;