feat: get GraphQL response field as defined by Jackson's JavaType

Author: BlasiusSecundus

graphql-spring-boot-test/src/main/java/com/graphql/spring/boot/test/GraphQLResponse.java

@@ -1,5 +1,6 @@
 package com.graphql.spring.boot.test;
 
+import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.graphql.spring.boot.test.assertions.GraphQLErrorListAssertion;
@@ -44,12 +45,15 @@ public String get(String path) {
     }
 
     public <T> T get(String path, Class<T> type) {
-        return mapper.convertValue(context.read(path, Object.class), type);
+        return mapper.convertValue(context.read(path), type);
+    }
+
+    public <T> T get(String path, JavaType type) {
+        return mapper.convertValue(context.read(path), type);
     }
 
     public <T> List<T> getList(String path, Class<T> type) {
-        final List<?> raw = context.read(path, List.class);
-        return mapper.convertValue(raw, mapper.getTypeFactory().constructCollectionType(List.class, type));
+        return get(path, mapper.getTypeFactory().constructCollectionType(List.class, type));
     }
 
     public ReadContext context() {

graphql-spring-boot-test/src/test/java/com/graphql/spring/boot/test/GraphQLResponseTest.java

@@ -1,5 +1,6 @@
 package com.graphql.spring.boot.test;
 
+import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.graphql.spring.boot.test.assertions.GraphQLErrorListAssertion;
 import com.graphql.spring.boot.test.assertions.GraphQLFieldAssert;
@@ -17,9 +18,14 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.json.JsonContentAssert;
+import org.springframework.core.io.ClassPathResource;
 import org.springframework.http.ResponseEntity;
+import org.springframework.util.StreamUtils;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.math.BigDecimal;
+import java.nio.charset.StandardCharsets;
 import java.time.LocalDate;
 import java.util.Arrays;
 import java.util.Collections;
@@ -121,6 +127,25 @@ public <T> void testGetList(
         assertThat(actual).containsExactlyElementsOf(expected);
     }
 
+    @DisplayName("Should get field as defined by Jackson's JavaType.")
+    @Test
+    public void testGetAsJavaType() throws IOException {
+        // GIVEN
+        final String dataPath = "$.data.externalList[*].fooList";
+        final String response = loadClassPathResource("response-with-nested-list.json");
+        final List<List<String>> expected = Arrays.asList(Arrays.asList("foo1", "foo2"),
+            Collections.singletonList("foo3"));
+        final JavaType stringList = objectMapper.getTypeFactory().constructCollectionType(List.class, String.class);
+        final JavaType listOfStringLists = objectMapper.getTypeFactory().constructCollectionType(List.class,
+            stringList);
+        // WHEN
+        final List<List<String>> actual = new GraphQLResponse(ResponseEntity.ok(response), objectMapper)
+            .get(dataPath, listOfStringLists);
+        // THEN
+        assertThat(actual).containsExactlyElementsOf(expected);
+
+    }
+
     @ParameterizedTest
     @ValueSource(strings = {
         "{\"data\": { \"foo\":\"bar\" } }",
@@ -242,10 +267,17 @@ void testJsonAssertion() {
             .containsExactly(graphQLResponse, path);
     }
 
+    private String loadClassPathResource(String path) throws IOException {
+        try(InputStream resourceStream = new ClassPathResource(path).getInputStream()) {
+            return StreamUtils.copyToString(resourceStream, StandardCharsets.UTF_8);
+        }
+    }
+
     @Data
     @AllArgsConstructor
     @NoArgsConstructor
     private static class FooBar {
+
         private String foo;
         private BigDecimal bar;
     }

graphql-spring-boot-test/src/test/resources/response-with-nested-list.json

@@ -0,0 +1,16 @@
+{
+  "data": {
+      "externalList": [
+        {
+          "fooList": [
+              "foo1", "foo2"
+          ]
+        },
+        {
+          "fooList": [
+              "foo3"
+          ]
+        }
+      ]
+  }
+}