chore: metaOnly flag in pre-aggregations api (#9461)

Author: RusovDmitriy

packages/cubejs-api-gateway/src/gateway.ts

@@ -440,6 +440,7 @@ class ApiGateway {
       app.get('/cubejs-system/v1/pre-aggregations', systemMiddlewares, systemAsyncHandler(async (req, res) => {
         await this.getPreAggregations({
           cacheOnly: !!req.query.cacheOnly,
+          metaOnly: !!req.query.metaOnly,
           context: req.context,
           res: this.resToResultFn(res)
         });
@@ -619,7 +620,7 @@ class ApiGateway {
     }
   }
 
-  public async getPreAggregations({ cacheOnly, context, res }: { cacheOnly?: boolean, context: RequestContext, res: ResponseResultFn }) {
+  public async getPreAggregations({ cacheOnly, metaOnly, context, res }: { cacheOnly?: boolean, metaOnly?: boolean, context: RequestContext, res: ResponseResultFn }) {
     const requestStarted = new Date();
     try {
       const compilerApi = await this.getCompilerApi(context);
@@ -634,6 +635,7 @@ class ApiGateway {
               preAggregations: preAggregations.map(p => ({
                 id: p.id,
                 cacheOnly,
+                metaOnly
               }))
             },
           )

packages/cubejs-api-gateway/src/query.js

@@ -280,6 +280,7 @@ const queryPreAggregationsSchema = Joi.object().keys({
   preAggregations: Joi.array().items(Joi.object().keys({
     id: Joi.string().required(),
     cacheOnly: Joi.boolean(),
+    metaOnly: Joi.boolean(),
     partitions: Joi.array().items(Joi.string()),
     refreshRange: Joi.array().items(Joi.string()).length(2), // TODO: Deprecate after cloud changes
   }))

packages/cubejs-server-core/src/core/RefreshScheduler.ts

@@ -33,6 +33,7 @@ type PreAggregationsQueryingOptions = {
   preAggregations: {
     id: string,
     cacheOnly?: boolean,
+    metaOnly?: boolean,
     partitions?: string[]
   }[],
   forceBuildPreAggregations?: boolean,
@@ -391,7 +392,17 @@ export class RefreshScheduler {
 
     return Promise.all(preAggregations.map(preAggregation => async () => {
       const { timezones } = queryingOptions;
-      const { partitions: partitionsFilter, cacheOnly } = preAggregationsQueryingOptions[preAggregation.id] || {};
+      const { partitions: partitionsFilter, cacheOnly, metaOnly } = preAggregationsQueryingOptions[preAggregation.id] || {};
+
+      if (metaOnly) {
+        return {
+          timezones,
+          preAggregation,
+          partitions: [],
+          errors: [],
+          partitionsWithDependencies: []
+        };
+      }
 
       const type = preAggregation?.preAggregation?.type;
       const isEphemeralPreAggregation = type === 'rollupJoin' || type === 'rollupLambda';