Properties for setting subscription keep alive

Author: oliemansm

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

@@ -2,7 +2,7 @@ spring:
   application:
     name: graphql-subscription-example
 server:
-  port: 9000
+  port: 9001
 
 graphql:
   servlet:

example-graphql-subscription/src/main/resources/public/index.html

@@ -62,6 +62,8 @@
         }
 
         function subscribeToStocks() {
+            // var exampleSocket = new WebSocket("ws://ceofs-seb-dot-shell-dtest.appspot.com:443/subscriptions");
+            // var exampleSocket = new WebSocket("ws://173.194.79.153:80/subscriptions");
             var exampleSocket = new WebSocket("ws://localhost:9000/subscriptions");
             networkBlip();
 

graphql-spring-boot-autoconfigure/src/main/java/com/oembedler/moon/graphql/boot/GraphQLSubscriptionApolloProperties.java

@@ -0,0 +1,14 @@
+package com.oembedler.moon.graphql.boot;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@Data
+@ConfigurationProperties("graphql.servlet.subscriptions.apollo")
+class GraphQLSubscriptionApolloProperties {
+
+    private boolean keepAliveEnabled = true;
+
+    private int keepAliveIntervalSeconds = 15;
+
+}

graphql-spring-boot-autoconfigure/src/main/java/com/oembedler/moon/graphql/boot/GraphQLToolsProperties.java

@@ -5,7 +5,6 @@
 import org.springframework.context.annotation.Configuration;
 
 @Data
-@Configuration
 @ConfigurationProperties(prefix = "graphql.tools")
 class GraphQLToolsProperties {
 

graphql-spring-boot-autoconfigure/src/main/java/com/oembedler/moon/graphql/boot/GraphQLWebsocketAutoConfiguration.java

@@ -1,13 +1,17 @@
 package com.oembedler.moon.graphql.boot;
 
 import graphql.schema.GraphQLSchema;
+import graphql.servlet.ApolloSubscriptionConnectionListener;
 import graphql.servlet.GraphQLInvocationInputFactory;
 import graphql.servlet.GraphQLObjectMapper;
 import graphql.servlet.GraphQLQueryInvoker;
 import graphql.servlet.GraphQLWebsocketServlet;
+import graphql.servlet.SubscriptionConnectionListener;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.condition.*;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.web.servlet.DispatcherServlet;
@@ -17,18 +21,32 @@
 import javax.websocket.ContainerProvider;
 import javax.websocket.WebSocketContainer;
 import javax.websocket.server.ServerContainer;
+import java.time.Duration;
 
 @Configuration
 @ConditionalOnWebApplication
 @ConditionalOnClass(DispatcherServlet.class)
 @ConditionalOnBean({GraphQLSchema.class})
 @ConditionalOnProperty(value = "graphql.servlet.websocket.enabled", havingValue = "true", matchIfMissing = true)
 @AutoConfigureAfter({GraphQLJavaToolsAutoConfiguration.class})
+@EnableConfigurationProperties(GraphQLSubscriptionApolloProperties.class)
 public class GraphQLWebsocketAutoConfiguration {
 
     @Value("${graphql.servlet.subscriptions.websocket.path:/subscriptions}")
     private String websocketPath;
 
+    @Autowired
+    private GraphQLSubscriptionApolloProperties apolloProperties;
+
+    @Bean
+    @ConditionalOnMissingBean
+    public SubscriptionConnectionListener subscriptionConnectionListener() {
+        if (!apolloProperties.isKeepAliveEnabled()) {
+            return ApolloSubscriptionConnectionListener.createWithKeepAliveDisabled();
+        }
+        return ApolloSubscriptionConnectionListener.createWithKeepAliveInterval(Duration.ofSeconds(apolloProperties.getKeepAliveIntervalSeconds()));
+    }
+
     @Bean
     @ConditionalOnMissingBean
     public GraphQLWebsocketServlet graphQLWebsocketServlet(GraphQLInvocationInputFactory invocationInputFactory, GraphQLQueryInvoker queryInvoker, GraphQLObjectMapper graphQLObjectMapper) {