spring-io · devysf · Oct 3, 2025
diff --git a/start-client/dev/api.mock.json b/start-client/dev/api.mock.json
@@ -1,19 +1,19 @@
 {
   "_links": {
     "maven-project": {
-      "href": "https://start.spring.io/starter.zip?type=maven-project{&dependencies,packaging,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
+      "href": "https://start.spring.io/starter.zip?type=maven-project{&dependencies,packaging,configurationFileFormat,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
       "templated": true
     },
     "maven-build": {
-      "href": "https://start.spring.io/pom.xml?type=maven-build{&dependencies,packaging,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
+      "href": "https://start.spring.io/pom.xml?type=maven-build{&dependencies,packaging,configurationFileFormat,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
       "templated": true
     },
     "gradle-project": {
-      "href": "https://start.spring.io/starter.zip?type=gradle-project{&dependencies,packaging,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
+      "href": "https://start.spring.io/starter.zip?type=gradle-project{&dependencies,packaging,configurationFileFormat,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
       "templated": true
     },
     "gradle-build": {
-      "href": "https://start.spring.io/build.gradle?type=gradle-build{&dependencies,packaging,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
+      "href": "https://start.spring.io/build.gradle?type=gradle-build{&dependencies,packaging,configurationFileFormat,javaVersion,language,bootVersion,groupId,artifactId,version,name,description,packageName}",
       "templated": true
     },
     "dependencies": {
@@ -1393,6 +1393,14 @@
       { "id": "war", "name": "War" }
     ]
   },
+  "configurationFileFormat": {
+    "type": "single-select",
+    "default": "properties",
+    "values": [
+      { "id": "properties", "name": "Properties" },
+      { "id": "yaml", "name": "YAML" }
+    ]
+  },
   "javaVersion": {
     "type": "single-select",
     "default": "1.8",

diff --git a/start-client/src/components/common/builder/Fields.js b/start-client/src/components/common/builder/Fields.js
@@ -108,6 +108,16 @@ function Fields({
                 </FieldError>
               )}
             </Control>
+            <Control text='Configuration File Format'>
+              <Radio
+                  name='configurationFileFormat'
+                  selected={get(values, 'configurationFileFormat')}
+                  options={get(config, 'lists.configurationFileFormat')}
+                  onChange={value => {
+                    update({ configurationFileFormat: value })
+                  }}
+              />
+            </Control>
             <Control text='Project Metadata'>
               <FieldInput
                 id='input-group'

diff --git a/start-client/src/components/reducer/Initializr.js b/start-client/src/components/reducer/Initializr.js
@@ -10,6 +10,7 @@ export const defaultInitializrContext = {
     project: '',
     language: '',
     boot: '',
+    configurationFileFormat: '',
     meta: {
       name: '',
       group: '',
@@ -41,6 +42,8 @@ const getPersistedOrDefault = json => {
     language:
       localStorage.getItem('language') || get(json, 'defaultValues').language,
     boot: get(json, 'defaultValues').boot,
+    configurationFileFormat:
+      localStorage.getItem('configurationFileFormat') || get(json, 'defaultValues').configurationFileFormat,
     meta: {
       name: get(json, 'defaultValues.meta').name,
       group: get(json, 'defaultValues.meta').group,
@@ -55,7 +58,7 @@ const getPersistedOrDefault = json => {
     },
     dependencies: [],
   }
-  const checks = ['project', 'language', 'meta.java', 'meta.packaging']
+  const checks = ['project', 'language', 'meta.java', 'meta.packaging', 'configurationFileFormat',]
   checks.forEach(key => {
     const item = get(json, `lists.${key}`)?.find(
       it => it.key === get(values, key)
@@ -80,6 +83,9 @@ const persist = changes => {
   if (get(changes, 'meta.java')) {
     localStorage.setItem('java', get(changes, 'meta.java'))
   }
+  if (get(changes, 'configurationFileFormat')) {
+    localStorage.setItem('configurationFileFormat', get(changes, 'configurationFileFormat'))
+  }
 }
 
 export function reducer(state, action) {

diff --git a/start-client/src/components/reducer/__tests__/Initializr.js b/start-client/src/components/reducer/__tests__/Initializr.js
@@ -23,6 +23,7 @@ describe('COMPLETE action', () => {
         project: '',
         language: '',
         boot: '',
+        configurationFileFormat: '',
         meta: {
           name: '',
           group: '',
@@ -47,7 +48,7 @@ describe('COMPLETE action', () => {
       },
     })
     expect(get(result, 'share')).toBe(
-      'type=maven-project&language=java&platformVersion=2.2.0.RELEASE&packaging=jar&jvmVersion=1.8&groupId=com.example&artifactId=demo&name=demo&description=Demo%20project%20for%20Spring%20Boot&packageName=com.example.demo&dependencies='
+      'type=maven-project&language=java&platformVersion=2.2.0.RELEASE&packaging=jar&configurationFileFormat=properties&jvmVersion=1.8&groupId=com.example&artifactId=demo&name=demo&description=Demo%20project%20for%20Spring%20Boot&packageName=com.example.demo&dependencies='
     )
     expect(get(result, 'values.project')).toBe('maven-project')
     expect(get(result, 'values.language')).toBe('java')
@@ -181,6 +182,15 @@ describe('UPDATE action', () => {
     })
     expect(get(result, 'values.meta.packaging')).toBe('war')
   })
+  it('should reduce the state (configuration file format)', () => {
+    const result = reducer(state, {
+      type: 'UPDATE',
+      payload: {
+        configurationFileFormat: 'yaml',
+      },
+    })
+    expect(get(result, 'values.configurationFileFormat')).toBe('yaml')
+  })
   it('should reduce the state (meta packageName)', () => {
     const result = reducer(state, {
       type: 'UPDATE',
@@ -217,6 +227,7 @@ describe('LOAD action', () => {
           description: 'Demo1 project for Spring Boot',
           groupId: 'com.example1',
           jvmVersion: '1.8',
+          configurationFileFormat: 'yaml',
           language: 'java',
           name: 'demo1',
           packageName: 'com.example1.demo1',
@@ -239,6 +250,7 @@ describe('LOAD action', () => {
     expect(get(result, 'values.meta.packaging')).toBe('war')
     expect(get(result, 'values.meta.packageName')).toBe('com.example1.demo1')
     expect(get(result, 'values.meta.java')).toBe('1.8')
+    expect(get(result, 'values.configurationFileFormat')).toBe('yaml')
     expect(get(result, 'values.dependencies').length).toBe(0)
     expect(Object.keys(get(result, 'errors')).length).toBe(0)
     expect(Object.keys(get(result, 'warnings')).length).toBe(0)

diff --git a/start-client/src/components/utils/ApiUtils.js b/start-client/src/components/utils/ApiUtils.js
@@ -10,6 +10,7 @@ const PROPERTIES_MAPPING_URL = {
   language: 'language',
   platformVersion: 'boot',
   packaging: 'meta.packaging',
+  configurationFileFormat: 'configurationFileFormat',
   jvmVersion: 'meta.java',
   groupId: 'meta.group',
   artifactId: 'meta.artifact',
@@ -24,7 +25,7 @@ export const getInfo = function getInfo(url) {
     fetch(`${url}`, {
       method: 'GET',
       headers: {
-        Accept: 'application/vnd.initializr.v2.2+json',
+        Accept: 'application/vnd.initializr.v2.3+json',
       },
     })
       .then(
@@ -82,6 +83,7 @@ export const parseParams = (values, queryParams, lists) => {
           case 'project':
           case 'language':
           case 'meta.packaging':
+          case 'configurationFileFormat':
           case 'meta.java': {
             const list = get(lists, key, [])
             const res = list.find(a => a.key.toLowerCase() === value)
@@ -229,6 +231,10 @@ export const getLists = json => {
         text: `${packaging.name}`,
       })),
     },
+    configurationFileFormat: get(json, 'configurationFileFormat.values', []).map(configurationFileFormat => ({
+      key: `${configurationFileFormat.id}`,
+      text: `${configurationFileFormat.name}`,
+    })),
     dependencies: deps,
   }
 }
@@ -238,6 +244,7 @@ export const getDefaultValues = json => {
     project: get(json, 'type.default'),
     language: get(json, 'language.default'),
     boot: get(json, 'bootVersion.default'),
+    configurationFileFormat: get(json, 'configurationFileFormat.default') || 'properties',
     meta: {
       name: get(json, 'name.default'),
       group: get(json, 'groupId.default'),
@@ -281,6 +288,7 @@ export const getProject = function getProject(url, values, config) {
       packageName: get(values, 'meta.packageName'),
       packaging: get(values, 'meta.packaging'),
       javaVersion: get(values, 'meta.java'),
+      configurationFileFormat: get(values, 'configurationFileFormat'),
     })
     let paramsDependencies = get(values, 'dependencies', [])
       .map(dependency => {