line · minwoox · Jun 30, 2026
@@ -152,15 +152,15 @@ void extractsNodeIpFromLabel() throws Exception {
         final Repository fooGroup = dogma.projectManager().get(XDS_CENTRAL_DOGMA_PROJECT)
                                          .repos().get("foo");
         final Entry<JsonNode> aggregatorEntry =
-                fooGroup.get(Revision.HEAD, Query.ofJson(
-                        K8S_ENDPOINT_AGGREGATORS_DIRECTORY + aggregatorId + ".json")).join();
+                fooGroup.get(Revision.HEAD, Query.ofYaml(
+                        K8S_ENDPOINT_AGGREGATORS_DIRECTORY + aggregatorId + ".yaml")).join();
 
         // KubernetesEndpointsUpdater commits the resolved endpoints in the next revision.
         await().until(() -> fooGroup.normalizeNow(Revision.HEAD)
                                     .equals(aggregatorEntry.revision().forward(1)));
 
         final Entry<JsonNode> endpointEntry = fooGroup.get(
-                Revision.HEAD, Query.ofJson(K8S_ENDPOINTS_DIRECTORY + aggregatorId + ".json")).join();
+                Revision.HEAD, Query.ofYaml(K8S_ENDPOINTS_DIRECTORY + aggregatorId + ".yaml")).join();
 
         // The endpoints must use the label values resolved by LabelBasedNodeIpExtractor,
         // not the default InternalIP addresses (1.1.1.1 / 2.2.2.2).
@@ -228,13 +228,13 @@ void fallsBackToInternalIpWhenLabelKeyIsAbsent() throws Exception {
         final Repository fooGroup = dogma.projectManager().get(XDS_CENTRAL_DOGMA_PROJECT)
                                          .repos().get("foo");
         final Entry<JsonNode> aggregatorEntry =
-                fooGroup.get(Revision.HEAD, Query.ofJson(
-                        K8S_ENDPOINT_AGGREGATORS_DIRECTORY + aggregatorId + ".json")).join();
+                fooGroup.get(Revision.HEAD, Query.ofYaml(
+                        K8S_ENDPOINT_AGGREGATORS_DIRECTORY + aggregatorId + ".yaml")).join();
         await().until(() -> fooGroup.normalizeNow(Revision.HEAD)
                                     .equals(aggregatorEntry.revision().forward(1)));
 
         final Entry<JsonNode> endpointEntry = fooGroup.get(
-                Revision.HEAD, Query.ofJson(K8S_ENDPOINTS_DIRECTORY + aggregatorId + ".json")).join();
+                Revision.HEAD, Query.ofYaml(K8S_ENDPOINTS_DIRECTORY + aggregatorId + ".yaml")).join();
         assertThatJson(endpointEntry.content()).isEqualTo(
                 '{' +
                 "  \"clusterName\": \"groups/foo/k8s/clusters/" + aggregatorId + "\"," +

@@ -40,7 +40,8 @@ public class ContentTransformer<T> {
      */
     public ContentTransformer(String path, EntryType entryType, BiFunction<Revision, T, T> transformer) {
         this.path = requireNonNull(path, "path");
-        checkArgument(entryType == EntryType.JSON, "entryType: %s (expected: %s)", entryType, EntryType.JSON);
+        checkArgument(entryType == EntryType.JSON || entryType == EntryType.YAML,
+                      "entryType: %s (expected: %s or %s)", entryType, EntryType.JSON, EntryType.YAML);
         this.entryType = requireNonNull(entryType, "entryType");
         this.transformer = requireNonNull(transformer, "transformer");
     }

@@ -37,6 +37,7 @@
 import com.linecorp.centraldogma.common.CentralDogmaException;
 import com.linecorp.centraldogma.common.Revision;
 import com.linecorp.centraldogma.internal.Jackson;
+import com.linecorp.centraldogma.internal.Yaml;
 import com.linecorp.centraldogma.server.storage.StorageException;
 
 abstract class AbstractChangesApplier {
@@ -98,6 +99,28 @@ public void apply(DirCacheEntry ent) {
         }
     }
 
+    static final class InsertYaml extends PathEdit {
+        private final ObjectInserter inserter;
+        private final JsonNode jsonNode;
+
+        InsertYaml(String entryPath, ObjectInserter inserter, JsonNode jsonNode) {
+            super(entryPath);
+            this.inserter = inserter;
+            this.jsonNode = jsonNode;
+        }
+
+        @Override
+        public void apply(DirCacheEntry ent) {
+            try {
+                final byte[] yamlBytes = Yaml.writeValueAsString(jsonNode).getBytes(UTF_8);
+                ent.setObjectId(inserter.insert(Constants.OBJ_BLOB, yamlBytes));
+                ent.setFileMode(FileMode.REGULAR_FILE);
+            } catch (IOException e) {
+                throw new StorageException("failed to create a new YAML blob", e);
+            }
+        }
+    }
+
     static final class InsertText extends PathEdit {
         private final ObjectInserter inserter;
         private final String text;

@@ -35,15 +35,16 @@
 import com.linecorp.centraldogma.common.EntryType;
 import com.linecorp.centraldogma.common.Revision;
 import com.linecorp.centraldogma.internal.Jackson;
+import com.linecorp.centraldogma.internal.Yaml;
 import com.linecorp.centraldogma.server.command.ContentTransformer;
 
 final class TransformingChangesApplier extends AbstractChangesApplier {
 
     private final ContentTransformer<JsonNode> transformer;
 
     TransformingChangesApplier(ContentTransformer<?> transformer) {
-        checkArgument(transformer.entryType() == EntryType.JSON,
-                      "transformer: %s (expected: JSON type)", transformer);
+        checkArgument(transformer.entryType() == EntryType.JSON || transformer.entryType() == EntryType.YAML,
+                      "transformer: %s (expected: JSON or YAML type)", transformer);
         //noinspection unchecked
         this.transformer = (ContentTransformer<JsonNode>) transformer;
     }
@@ -55,13 +56,23 @@ int doApply(Revision headRevision, DirCache dirCache,
         final DirCacheEntry oldEntry = dirCache.getEntry(changePath);
         final byte[] oldContent = oldEntry != null ? reader.open(oldEntry.getObjectId()).getBytes()
                                                    : null;
-        final JsonNode oldJsonNode = oldContent != null ? Jackson.readTree(oldContent)
-                                                        : JsonNodeFactory.instance.nullNode();
+        final JsonNode oldJsonNode;
+        if (oldContent == null) {
+            oldJsonNode = JsonNodeFactory.instance.nullNode();
+        } else if (transformer.entryType() == EntryType.YAML) {
+            oldJsonNode = Yaml.readTree(oldContent);
+        } else {
+            oldJsonNode = Jackson.readTree(oldContent);
+        }
         try {
             final JsonNode newJsonNode = transformer.transformer().apply(headRevision, oldJsonNode.deepCopy());
             requireNonNull(newJsonNode, "transformer.transformer().apply() returned null");
             if (!Objects.equals(newJsonNode, oldJsonNode)) {
-                applyPathEdit(dirCache, new InsertJson(changePath, inserter, newJsonNode));
+                if (transformer.entryType() == EntryType.YAML) {
+                    applyPathEdit(dirCache, new InsertYaml(changePath, inserter, newJsonNode));
+                } else {
+                    applyPathEdit(dirCache, new InsertJson(changePath, inserter, newJsonNode));
+                }
                 return 1;
             }
         } catch (CentralDogmaException e) {

@@ -22,7 +22,7 @@ import { useGetGroupHistoryQuery, useGetResourceQuery } from 'dogma/features/xds
 
 // The aggregator writes its generated endpoints to this path; reading it tells us whether (and when) the
 // aggregator has produced endpoints from Kubernetes.
-const generatedPath = (id: string) => `/k8s/endpoints/${id}.json`;
+const generatedPath = (id: string) => `/k8s/endpoints/${id}.yaml`;
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 function countEndpoints(content: any): { localities: number; endpoints: number } {

@@ -48,17 +48,17 @@ export interface GroupDto {
 
 export interface XdsResourceDto {
   // The resource id, i.e. the file path under the type directory without the
-  // leading '/{type}/' prefix and the trailing '.json' suffix.
+  // leading '/{type}/' prefix and the trailing file extension (.yaml or .json).
   id: string;
-  // The full repository path, e.g. '/clusters/foo.json'.
+  // The full repository path, e.g. '/clusters/foo.yaml'.
   path: string;
   revision: number;
 }
 
-// The full xDS resource name derived from its repository path, e.g. group 'foo' + '/clusters/c1.json'
+// The full xDS resource name derived from its repository path, e.g. group 'foo' + '/clusters/c1.yaml'
 // becomes 'groups/foo/clusters/c1'. This matches the `name` the server assigns to CDS/LDS/RDS resources.
 export function resourceName(group: string, path: string): string {
-  return `groups/${group}${path.replace(/\.json$/, '')}`;
+  return `groups/${group}${path.replace(/\.(json|yaml)$/, '')}`;
 }
 
 // A starter template offered when creating a new resource of each type.

@@ -15,7 +15,7 @@
  */
 
 import { createApi } from '@reduxjs/toolkit/query/react';
-import { FetchBaseQueryError } from '@reduxjs/toolkit/query';
+import { FetchBaseQueryError, FetchArgs } from '@reduxjs/toolkit/query';
 import { baseQueryWithReauth } from 'dogma/features/api/baseQuery';
 import { createLoginUrl } from 'dogma/util/auth';
 import {
@@ -53,7 +53,7 @@ interface RawRepoDto {
 
 interface RawFileDto {
   path: string;
-  type: 'TEXT' | 'DIRECTORY' | 'JSON' | 'YML';
+  type: 'TEXT' | 'DIRECTORY' | 'JSON' | 'YAML';
   revision: number;
 }
 
@@ -68,26 +68,26 @@ export interface FileContentDto {
 
 export type ResourceArg = { group: string; type: XdsResourceType };
 // `k8s` marks an endpoint generated by a k8s aggregator (stored under '/k8s/endpoints/'); it is read-only.
-export type ResourceIdArg = ResourceArg & { id: string; k8s?: boolean };
+// `path` is the full repository path (e.g. '/clusters/foo.yaml') — when provided, it is used directly to
+// avoid a .yaml→.json fallback request on servers that still have legacy .json files.
+export type ResourceIdArg = ResourceArg & { id: string; k8s?: boolean; path?: string };
 export type CreateResourceArg = ResourceArg & { id: string; body: string };
 export type UpdateResourceArg = ResourceIdArg & { body: string };
 
 // Derives a Kubernetes endpoint aggregator id from its repository file path, e.g.
-// '/k8s/endpointAggregators/foo.json' becomes 'foo'.
+// '/k8s/endpointAggregators/foo.yaml' becomes 'foo'.
 function k8sAggregatorIdFromPath(path: string): string {
   let id = path;
   const prefix = '/k8s/endpointAggregators/';
   if (id.startsWith(prefix)) {
     id = id.substring(prefix.length);
   }
-  if (id.endsWith('.json')) {
-    id = id.substring(0, id.length - '.json'.length);
-  }
+  id = id.replace(/\.(json|yaml)$/, '');
   return id;
 }
 
 // Derives a resource id from a repository file path, e.g.
-// '/clusters/foo/bar.json' with type 'clusters' becomes 'foo/bar'.
+// '/clusters/foo/bar.yaml' with type 'clusters' becomes 'foo/bar'.
 function idFromPath(path: string, type: XdsResourceType): string {
   let id = path;
   if (id.startsWith('/')) {
@@ -97,9 +97,7 @@ function idFromPath(path: string, type: XdsResourceType): string {
   if (id.startsWith(prefix)) {
     id = id.substring(prefix.length);
   }
-  if (id.endsWith('.json')) {
-    id = id.substring(0, id.length - '.json'.length);
-  }
+  id = id.replace(/\.(json|yaml)$/, '');
   return id;
 }
 
@@ -110,6 +108,40 @@ function encodeResourcePath(id: string): string {
   return id.split('/').map(encodeURIComponent).join('/');
 }
 
+// Fetches a file by its full repository path, falling back from .yaml to .json for legacy servers.
+// Pass `path` (including extension) when known from a listing response to skip the fallback round-trip.
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+type FetchFn = (arg: string | FetchArgs) => any;
+
+async function fetchYamlOrJson(
+  group: string,
+  basePath: string,
+  fetchWithBQ: FetchFn,
+  knownPath?: string,
+): Promise<{ data: FileContentDto } | { error: FetchBaseQueryError }> {
+  if (knownPath) {
+    const direct = await fetchWithBQ(
+      `/api/v1/projects/${XDS_PROJECT}/repos/${group}/contents${knownPath}?revision=head`,
+    );
+    if (!direct.error) return { data: direct.data as FileContentDto };
+    if ((direct.error as FetchBaseQueryError).status !== 404) {
+      return { error: direct.error as FetchBaseQueryError };
+    }
+  }
+  const yamlResult = await fetchWithBQ(
+    `/api/v1/projects/${XDS_PROJECT}/repos/${group}/contents${basePath}.yaml?revision=head`,
+  );
+  if (!yamlResult.error) return { data: yamlResult.data as FileContentDto };
+  if ((yamlResult.error as FetchBaseQueryError).status !== 404) {
+    return { error: yamlResult.error as FetchBaseQueryError };
+  }
+  const jsonResult = await fetchWithBQ(
+    `/api/v1/projects/${XDS_PROJECT}/repos/${group}/contents${basePath}.json?revision=head`,
+  );
+  if (jsonResult.error) return { error: jsonResult.error as FetchBaseQueryError };
+  return { data: jsonResult.data as FileContentDto };
+}
+
 export const xdsApiSlice = createApi({
   reducerPath: 'xdsApi',
   // The login page is in the main web app at the server root (outside the '/xds' basePath), so navigate out
@@ -168,7 +200,7 @@ export const xdsApiSlice = createApi({
             // clean id. They are flagged read-only by their path in the UI.
             id:
               type === 'endpoints' && file.path.startsWith('/k8s/endpoints/')
-                ? file.path.slice('/k8s/endpoints/'.length).replace(/\.json$/, '')
+                ? file.path.slice('/k8s/endpoints/'.length).replace(/\.(json|yaml)$/, '')
                 : idFromPath(file.path, type),
             path: file.path,
             revision: file.revision,
@@ -181,12 +213,17 @@ export const xdsApiSlice = createApi({
       // Endpoints (EDS) are not access-controlled, so they are read through a dedicated ungated API instead
       // of the generic content API which requires the READ repository role. k8s-aggregator-generated endpoints
       // live under '/k8s/endpoints/' and are read via their own path.
-      query: ({ group, type, id, k8s }) =>
-        type === 'endpoints'
-          ? k8s
+      async queryFn({ group, type, id, k8s, path }, _queryApi, _extraOptions, fetchWithBQ) {
+        if (type === 'endpoints') {
+          const url = k8s
             ? `/api/v1/xds/groups/${group}/k8s/endpoints/${id}`
-            : `/api/v1/xds/groups/${group}/endpoints/${id}`
-          : `/api/v1/projects/${XDS_PROJECT}/repos/${group}/contents/${type}/${id}.json?revision=head`,
+            : `/api/v1/xds/groups/${group}/endpoints/${id}`;
+          const result = await fetchWithBQ(url);
+          if (result.error) return { error: result.error as FetchBaseQueryError };
+          return { data: result.data as FileContentDto };
+        }
+        return fetchYamlOrJson(group, `/${type}/${id}`, fetchWithBQ, path);
+      },
       providesTags: ['Resource'],
     }),
     createResource: builder.mutation<unknown, CreateResourceArg>({
@@ -240,9 +277,10 @@ export const xdsApiSlice = createApi({
       },
       providesTags: ['K8sAggregator'],
     }),
-    getK8sAggregator: builder.query<FileContentDto, { group: string; id: string }>({
-      query: ({ group, id }) =>
-        `/api/v1/projects/${XDS_PROJECT}/repos/${group}/contents/k8s/endpointAggregators/${id}.json?revision=head`,
+    getK8sAggregator: builder.query<FileContentDto, { group: string; id: string; path?: string }>({
+      async queryFn({ group, id, path }, _queryApi, _extraOptions, fetchWithBQ) {
+        return fetchYamlOrJson(group, `/k8s/endpointAggregators/${id}`, fetchWithBQ, path);
+      },
       providesTags: ['K8sAggregator'],
     }),
     // Dry-run preview: resolves the aggregator's watchers against Kubernetes and returns the
@@ -394,7 +432,7 @@ export const xdsApiSlice = createApi({
 
         const idOf = (type: XdsResourceType, path: string): string =>
           type === 'endpoints' && path.startsWith('/k8s/endpoints/')
-            ? path.slice('/k8s/endpoints/'.length).replace(/\.json$/, '')
+            ? path.slice('/k8s/endpoints/'.length).replace(/\.(json|yaml)$/, '')
             : idFromPath(path, type);
 
         const nodes: XdsGraphNode[] = [];

@@ -78,8 +78,8 @@ public void createCluster(CreateClusterRequest request, StreamObserver<Cluster>
                          // can be set to false via the update API.
                          .setRespectDnsTtl(true)
                          .build();
-        xdsResourceManager.push(responseObserver, group, clusterName, CLUSTERS_DIRECTORY + clusterId + ".json",
-                                "Create cluster: " + clusterName, cluster, currentAuthor(), true);
+        xdsResourceManager.push(responseObserver, group, clusterName, CLUSTERS_DIRECTORY + clusterId + ".yaml",
+                                "Create cluster: " + clusterName, cluster, currentAuthor());
     }
 
     @Override

@@ -78,7 +78,7 @@ public void createEndpoint(CreateEndpointRequest request,
                                                       .setClusterName(clusterName)
                                                       .build();
         xdsResourceManager.push(responseObserver, group, clusterName, fileName(endpointId),
-                                "Create endpoint: " + clusterName, endpoint, currentAuthor(), true);
+                                "Create endpoint: " + clusterName, endpoint, currentAuthor());
     }
 
     private static String clusterName(String parent, String endpointId) {
@@ -125,7 +125,7 @@ private static Matcher checkEndpointName(String endpointName) {
     }
 
     private static String fileName(String endpointId) {
-        return ENDPOINTS_DIRECTORY + endpointId + ".json";
+        return ENDPOINTS_DIRECTORY + endpointId + ".yaml";
     }
 
     @Override