Added ability to cache the whole graphql response

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/BatchedQueryResponseWriter.java

@@ -2,22 +2,29 @@
 
 import graphql.ExecutionResult;
 import graphql.kickstart.execution.GraphQLObjectMapper;
+import graphql.kickstart.execution.input.GraphQLInvocationInput;
+import graphql.kickstart.servlet.cache.CachedResponse;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.Iterator;
 import java.util.List;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import lombok.RequiredArgsConstructor;
 
+@Slf4j
 @RequiredArgsConstructor
 class BatchedQueryResponseWriter implements QueryResponseWriter {
 
   private final List<ExecutionResult> results;
   private final GraphQLObjectMapper graphQLObjectMapper;
+  private final GraphQLInvocationInput invocationInput;
 
   @Override
-  public void write(HttpServletRequest request, HttpServletResponse response) throws IOException {
+  public void write(HttpServletRequest request, HttpServletResponse response, GraphQLResponseCache responseCache) throws IOException {
     response.setContentType(HttpRequestHandler.APPLICATION_JSON_UTF8);
     response.setStatus(HttpRequestHandler.STATUS_OK);
 
@@ -34,6 +41,16 @@ public void write(HttpServletRequest request, HttpServletResponse response) thro
 
     String responseContent = responseBuilder.toString();
     byte[] contentBytes = responseContent.getBytes(StandardCharsets.UTF_8);
+
+    if (responseCache != null && responseCache.isCacheable(request, invocationInput)) {
+      try {
+        responseCache.put(request, invocationInput, CachedResponse.ofContent(contentBytes));
+      } catch (Throwable t) {
+        log.warn(t.getMessage(), t);
+        log.warn("Ignore read from cache, unexpected error happened");
+      }
+    }
+
     response.setContentLength(contentBytes.length);
     response.getOutputStream().write(contentBytes);
   }

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/ErrorQueryResponseWriter.java

@@ -3,16 +3,31 @@
 import java.io.IOException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+
+import graphql.kickstart.execution.input.GraphQLInvocationInput;
+import graphql.kickstart.servlet.cache.CachedResponse;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 
+@Slf4j
 @RequiredArgsConstructor
 class ErrorQueryResponseWriter implements QueryResponseWriter {
 
   private final int statusCode;
   private final String message;
+  private final GraphQLInvocationInput invocationInput;
 
   @Override
-  public void write(HttpServletRequest request, HttpServletResponse response) throws IOException {
+  public void write(HttpServletRequest request, HttpServletResponse response, GraphQLResponseCache responseCache) throws IOException {
+    if (responseCache != null && responseCache.isCacheable(request, invocationInput)) {
+      try {
+        responseCache.put(request, invocationInput, CachedResponse.ofError(statusCode, message));
+      } catch (Throwable t) {
+        log.warn(t.getMessage(), t);
+        log.warn("Ignore read from cache, unexpected error happened");
+      }
+    }
     response.sendError(statusCode, message);
   }
 

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/GraphQLConfiguration.java

@@ -4,6 +4,7 @@
 import graphql.kickstart.execution.GraphQLObjectMapper;
 import graphql.kickstart.execution.GraphQLQueryInvoker;
 import graphql.kickstart.execution.context.ContextSetting;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
 import graphql.kickstart.servlet.config.DefaultGraphQLSchemaServletProvider;
 import graphql.kickstart.servlet.config.GraphQLSchemaServletProvider;
 import graphql.kickstart.servlet.context.GraphQLServletContextBuilder;
@@ -33,12 +34,13 @@ public class GraphQLConfiguration {
   private final Executor asyncExecutor;
   private final long subscriptionTimeout;
   private final ContextSetting contextSetting;
+  private final GraphQLResponseCache responseCache;
 
   private GraphQLConfiguration(GraphQLInvocationInputFactory invocationInputFactory,
       GraphQLQueryInvoker queryInvoker,
       GraphQLObjectMapper objectMapper, List<GraphQLServletListener> listeners, boolean asyncServletModeEnabled,
       Executor asyncExecutor, long subscriptionTimeout, ContextSetting contextSetting,
-      Supplier<BatchInputPreProcessor> batchInputPreProcessor) {
+      Supplier<BatchInputPreProcessor> batchInputPreProcessor, GraphQLResponseCache responseCache) {
     this.invocationInputFactory = invocationInputFactory;
     this.queryInvoker = queryInvoker;
     this.graphQLInvoker = queryInvoker.toGraphQLInvoker();
@@ -49,6 +51,7 @@ private GraphQLConfiguration(GraphQLInvocationInputFactory invocationInputFactor
     this.subscriptionTimeout = subscriptionTimeout;
     this.contextSetting = contextSetting;
     this.batchInputPreProcessor = batchInputPreProcessor;
+    this.responseCache = responseCache;
   }
 
   public static GraphQLConfiguration.Builder with(GraphQLSchema schema) {
@@ -109,6 +112,10 @@ public BatchInputPreProcessor getBatchInputPreProcessor() {
     return batchInputPreProcessor.get();
   }
 
+  public GraphQLResponseCache getResponseCache() {
+    return responseCache;
+  }
+
   public static class Builder {
 
     private GraphQLInvocationInputFactory.Builder invocationInputFactoryBuilder;
@@ -121,6 +128,7 @@ public static class Builder {
     private long subscriptionTimeout = 0;
     private ContextSetting contextSetting = ContextSetting.PER_QUERY_WITH_INSTRUMENTATION;
     private Supplier<BatchInputPreProcessor> batchInputPreProcessorSupplier = () -> new NoOpBatchInputPreProcessor();
+    private GraphQLResponseCache responseCache;
 
     private Builder(GraphQLInvocationInputFactory.Builder invocationInputFactoryBuilder) {
       this.invocationInputFactoryBuilder = invocationInputFactoryBuilder;
@@ -199,6 +207,11 @@ public Builder with(Supplier<BatchInputPreProcessor> batchInputPreProcessor) {
       return this;
     }
 
+    public Builder with(GraphQLResponseCache responseCache) {
+      this.responseCache = responseCache;
+      return this;
+    }
+
     public GraphQLConfiguration build() {
       return new GraphQLConfiguration(
           this.invocationInputFactory != null ? this.invocationInputFactory : invocationInputFactoryBuilder.build(),
@@ -209,7 +222,8 @@ public GraphQLConfiguration build() {
           asyncExecutor,
           subscriptionTimeout,
           contextSetting,
-          batchInputPreProcessorSupplier
+          batchInputPreProcessorSupplier,
+          responseCache
       );
     }
 

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/HttpRequestHandler.java

@@ -3,7 +3,7 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-interface HttpRequestHandler {
+public interface HttpRequestHandler {
 
   String APPLICATION_JSON_UTF8 = "application/json;charset=UTF-8";
   String APPLICATION_EVENT_STREAM_UTF8 = "text/event-stream;charset=UTF-8";

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/HttpRequestHandlerImpl.java

@@ -3,15 +3,18 @@
 import graphql.GraphQLException;
 import graphql.kickstart.execution.GraphQLInvoker;
 import graphql.kickstart.execution.GraphQLQueryResult;
-import graphql.kickstart.servlet.input.BatchInputPreProcessResult;
-import graphql.kickstart.servlet.input.BatchInputPreProcessor;
 import graphql.kickstart.execution.input.GraphQLBatchedInvocationInput;
 import graphql.kickstart.execution.input.GraphQLInvocationInput;
 import graphql.kickstart.execution.input.GraphQLSingleInvocationInput;
-import java.io.IOException;
+import graphql.kickstart.servlet.cache.CacheResponseWriter;
+import graphql.kickstart.servlet.cache.CachedResponse;
+import graphql.kickstart.servlet.input.BatchInputPreProcessResult;
+import graphql.kickstart.servlet.input.BatchInputPreProcessor;
+import lombok.extern.slf4j.Slf4j;
+
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import lombok.extern.slf4j.Slf4j;
+import java.io.IOException;
 
 @Slf4j
 class HttpRequestHandlerImpl implements HttpRequestHandler {
@@ -49,11 +52,31 @@ public void handle(HttpServletRequest request, HttpServletResponse response) thr
   private void execute(GraphQLInvocationInput invocationInput, HttpServletRequest request,
       HttpServletResponse response) {
     try {
+      if (configuration.getResponseCache() != null) {
+        CachedResponse cachedResponse = null;
+        try {
+          cachedResponse = configuration.getResponseCache().get(request, invocationInput);
+        } catch (Throwable t) {
+          log.warn(t.getMessage(), t);
+          log.warn("Ignore read from cache, unexpected error happened");
+        }
+
+        if (cachedResponse != null) {
+          CacheResponseWriter cacheResponseWriter = new CacheResponseWriter();
+          cacheResponseWriter.write(request, response, cachedResponse);
+          return;
+        }
+      }
+
       GraphQLQueryResult queryResult = invoke(invocationInput, request, response);
 
-      QueryResponseWriter queryResponseWriter = QueryResponseWriter.createWriter(queryResult, configuration.getObjectMapper(),
-          configuration.getSubscriptionTimeout());
-      queryResponseWriter.write(request, response);
+      QueryResponseWriter queryResponseWriter = QueryResponseWriter.createWriter(
+              queryResult,
+              configuration.getObjectMapper(),
+              configuration.getSubscriptionTimeout(),
+              invocationInput
+      );
+      queryResponseWriter.write(request, response, configuration.getResponseCache());
     } catch (Throwable t) {
       response.setStatus(STATUS_BAD_REQUEST);
       log.info("Bad GET request: path was not \"/schema.json\" or no query variable named \"query\" given");

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/QueryResponseWriter.java

@@ -2,6 +2,9 @@
 
 import graphql.kickstart.execution.GraphQLQueryResult;
 import graphql.kickstart.execution.GraphQLObjectMapper;
+import graphql.kickstart.execution.input.GraphQLInvocationInput;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
+
 import java.io.IOException;
 import java.util.Objects;
 import javax.servlet.http.HttpServletRequest;
@@ -12,20 +15,21 @@ interface QueryResponseWriter {
   static QueryResponseWriter createWriter(
       GraphQLQueryResult result,
       GraphQLObjectMapper graphQLObjectMapper,
-      long subscriptionTimeout
+      long subscriptionTimeout,
+      GraphQLInvocationInput invocationInput
   ) {
     Objects.requireNonNull(result, "GraphQL query result cannot be null");
 
     if (result.isBatched()) {
-      return new BatchedQueryResponseWriter(result.getResults(), graphQLObjectMapper);
+      return new BatchedQueryResponseWriter(result.getResults(), graphQLObjectMapper, invocationInput);
     } else if (result.isAsynchronous()) {
-      return new SingleAsynchronousQueryResponseWriter(result.getResult(), graphQLObjectMapper, subscriptionTimeout);
+      return new SingleAsynchronousQueryResponseWriter(result.getResult(), graphQLObjectMapper, subscriptionTimeout, invocationInput);
     } else if (result.isError()) {
-      return new ErrorQueryResponseWriter(result.getStatusCode(), result.getMessage());
+      return new ErrorQueryResponseWriter(result.getStatusCode(), result.getMessage(), invocationInput);
     }
-    return new SingleQueryResponseWriter(result.getResult(), graphQLObjectMapper);
+    return new SingleQueryResponseWriter(result.getResult(), graphQLObjectMapper, invocationInput);
   }
 
-  void write(HttpServletRequest request, HttpServletResponse response) throws IOException;
+  void write(HttpServletRequest request, HttpServletResponse response, GraphQLResponseCache responseCache) throws IOException;
 
 }

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleAsynchronousQueryResponseWriter.java

@@ -10,21 +10,31 @@
 import javax.servlet.AsyncContext;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+
+import graphql.kickstart.execution.input.GraphQLInvocationInput;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 import org.reactivestreams.Publisher;
 import org.reactivestreams.Subscription;
 
+@Slf4j
 @RequiredArgsConstructor
 class SingleAsynchronousQueryResponseWriter implements QueryResponseWriter {
 
   @Getter
   private final ExecutionResult result;
   private final GraphQLObjectMapper graphQLObjectMapper;
   private final long subscriptionTimeout;
+  private final GraphQLInvocationInput invocationInput;
 
   @Override
-  public void write(HttpServletRequest request, HttpServletResponse response) {
+  public void write(HttpServletRequest request, HttpServletResponse response, GraphQLResponseCache responseCache) {
+    if (responseCache != null) {
+      log.warn("Response cache for asynchronous query are not implemented yet");
+    }
+
     Objects.requireNonNull(request, "Http servlet request cannot be null");
     response.setContentType(HttpRequestHandler.APPLICATION_EVENT_STREAM_UTF8);
     response.setStatus(HttpRequestHandler.STATUS_OK);

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleQueryResponseWriter.java

@@ -2,26 +2,42 @@
 
 import graphql.ExecutionResult;
 import graphql.kickstart.execution.GraphQLObjectMapper;
+import graphql.kickstart.execution.input.GraphQLInvocationInput;
+import graphql.kickstart.servlet.cache.CachedResponse;
+import graphql.kickstart.servlet.cache.GraphQLResponseCache;
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+@Slf4j
 @RequiredArgsConstructor
 class SingleQueryResponseWriter implements QueryResponseWriter {
 
   private final ExecutionResult result;
   private final GraphQLObjectMapper graphQLObjectMapper;
+  private final GraphQLInvocationInput invocationInput;
 
   @Override
-  public void write(HttpServletRequest request, HttpServletResponse response) throws IOException {
+  public void write(HttpServletRequest request, HttpServletResponse response, GraphQLResponseCache responseCache) throws IOException {
     response.setContentType(HttpRequestHandler.APPLICATION_JSON_UTF8);
     response.setStatus(HttpRequestHandler.STATUS_OK);
     response.setCharacterEncoding(StandardCharsets.UTF_8.name());
     String responseContent = graphQLObjectMapper.serializeResultAsJson(result);
     byte[] contentBytes = responseContent.getBytes(StandardCharsets.UTF_8);
+
+    if (responseCache != null && responseCache.isCacheable(request, invocationInput)) {
+      try {
+        responseCache.put(request, invocationInput, CachedResponse.ofContent(contentBytes));
+      } catch (Throwable t) {
+        log.warn(t.getMessage(), t);
+        log.warn("Ignore read from cache, unexpected error happened");
+      }
+    }
+
     response.setContentLength(contentBytes.length);
     response.getOutputStream().write(contentBytes);
   }

graphql-java-servlet/src/main/java/graphql/kickstart/servlet/cache/CacheResponseWriter.java

@@ -0,0 +1,25 @@
+package graphql.kickstart.servlet.cache;
+
+import graphql.kickstart.servlet.HttpRequestHandler;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+public class CacheResponseWriter {
+
+  public void write(HttpServletRequest request, HttpServletResponse response, CachedResponse cachedResponse)
+      throws IOException {
+    if (cachedResponse.isError()) {
+      response.sendError(cachedResponse.getErrorStatusCode(), cachedResponse.getErrorMessage());
+    } else {
+      response.setContentType(HttpRequestHandler.APPLICATION_JSON_UTF8);
+      response.setStatus(HttpRequestHandler.STATUS_OK);
+      response.setCharacterEncoding(StandardCharsets.UTF_8.name());
+      response.setContentLength(cachedResponse.getContentBytes().length);
+      response.getOutputStream().write(cachedResponse.getContentBytes());
+    }
+  }
+
+}