Add support for creating a toString() method on generated classes (#13)

Author: timw6n

README.md

@@ -27,7 +27,7 @@ Please refer to:
 | modelNamePrefix           | String             | Empty                                 | Sets the prefix for GraphQL model classes (type, input, interface, enum, union). |
 | modelNameSuffix           | String             | Empty                                 | Sets the suffix for GraphQL model classes (type, input, interface, enum, union). |
 | generateEqualsAndHashCode | Boolean            | False                                 | Specifies whether generated model classes should have equals and hashCode methods defined. |
-
+| generateToString          | Boolean            | False                                 | Specifies whether generated model classes should have toString method defined. |
 
 ### Inspired by
 [swagger-codegen](https://github.com/swagger-api/swagger-codegen)

src/main/java/com/kobylynskyi/graphql/codegen/mapper/InputDefinitionToDataModelMapper.java

@@ -31,6 +31,7 @@ public static Map<String, Object> map(MappingConfig mappingConfig, InputObjectTy
         dataModel.put(NAME, typeDefinition.getName());
         dataModel.put(FIELDS, InputValueDefinitionToParameterMapper.map(mappingConfig, typeDefinition.getInputValueDefinitions(), typeDefinition.getName()));
         dataModel.put(EQUALS_AND_HASH_CODE, mappingConfig.isGenerateEqualsAndHashCode());
+        dataModel.put(TO_STRING, mappingConfig.isGenerateToString());
         return dataModel;
     }
 

src/main/java/com/kobylynskyi/graphql/codegen/mapper/TypeDefinitionToDataModelMapper.java

@@ -49,6 +49,7 @@ public static Map<String, Object> map(MappingConfig mappingConfig, ObjectTypeDef
                 .forEach(allParameters::addAll);
         dataModel.put(FIELDS, allParameters);
         dataModel.put(EQUALS_AND_HASH_CODE, mappingConfig.isGenerateEqualsAndHashCode());
+        dataModel.put(TO_STRING, mappingConfig.isGenerateToString());
 
         return dataModel;
     }

src/main/java/com/kobylynskyi/graphql/codegen/model/DataModelFields.java

@@ -15,4 +15,6 @@ public final class DataModelFields {
     public static final String IMPLEMENTS = "implements";
     public static final String OPERATIONS = "operations";
     public static final String EQUALS_AND_HASH_CODE = "equalsAndHashCode";
+    public static final String TO_STRING = "toString";
+
 }

src/main/java/com/kobylynskyi/graphql/codegen/model/DefaultMappingConfigValues.java

@@ -5,4 +5,5 @@ public class DefaultMappingConfigValues {
     public static final String DEFAULT_VALIDATION_ANNOTATION = "javax.validation.constraints.NotNull";
     public static final boolean DEFAULT_GENERATE_APIS = true;
     public static final boolean DEFAULT_EQUALS_AND_HASHCODE = false;
+    public static final boolean DEFAULT_TO_STRING = false;
 }

src/main/java/com/kobylynskyi/graphql/codegen/model/MappingConfig.java

@@ -29,6 +29,7 @@ public class MappingConfig {
     private String modelNameSuffix;
     private String modelValidationAnnotation = DefaultMappingConfigValues.DEFAULT_VALIDATION_ANNOTATION;
     private boolean generateEqualsAndHashCode = DefaultMappingConfigValues.DEFAULT_EQUALS_AND_HASHCODE;
+    private boolean generateToString = DefaultMappingConfigValues.DEFAULT_TO_STRING;
 
     public void putCustomTypeMappingIfAbsent(String from, String to) {
         if (customTypesMapping == null) {

src/main/resources/templates/javaClassGraphqlType.ftl

@@ -58,4 +58,16 @@ public class ${className} <#if implements?has_content>implements <#list implemen
 </#if>
     }
 </#if>
+<#if toString>
+    @Override
+    public String toString() {
+        return "${className}{"
+<#if fields?has_content>
+<#list fields as field>
+            + "${field.name}='" + ${field.name} + "'<#if field_has_next>,</#if>"
+</#list>
+</#if>
+            + "}";
+    }
+</#if>
 }

src/test/java/com/kobylynskyi/graphql/codegen/GraphqlCodegenTest.java

@@ -244,6 +244,30 @@ void generate_EqualsAndHashCode() throws Exception {
                         .map(File::getPath).findFirst().orElseThrow(FileNotFoundException::new)));
     }
 
+    @Test
+    void generate_toString() throws Exception {
+        mappingConfig.setGenerateToString(true);
+        mappingConfig.setModelNameSuffix("TO");
+
+        generator.generate();
+
+        File[] files = Objects.requireNonNull(outputJavaClassesDir.listFiles());
+        assertNotEquals(files.length, 0);
+
+        for (File eventFile : files) {
+            if (eventFile.getName().endsWith("TO.java")) {
+                String content = Utils.getFileContent(eventFile.getPath());
+
+                if (content.contains("public interface ") || content.contains("public enum ")) {
+                    continue;
+                }
+
+                assertThat(content,
+                    StringContains.containsString("public String toString()"));
+            }
+        }
+    }
+
     @Test
     void generate_NoSchemas() throws Exception {
         generator.setSchemas(Collections.emptyList());
@@ -299,4 +323,4 @@ void generate_OnlyModel() throws Exception {
         assertEquals(Arrays.asList("Event.java", "EventProperty.java", "EventStatus.java"), generatedFileNames);
     }
 
-}
+}