feat: RefreshKeys helper extension of popular implementations

Author: paveltiunov

packages/cubejs-schema-compiler/compiler/PrepareCompiler.js

@@ -9,6 +9,7 @@ const ContextEvaluator = require('./ContextEvaluator');
 const DashboardTemplateEvaluator = require('./DashboardTemplateEvaluator');
 const JoinGraph = require('./JoinGraph');
 const Funnels = require('../extensions/Funnels');
+const RefreshKeys = require('../extensions/RefreshKeys');
 const CubeToMetaTransformer = require('./CubeToMetaTransformer');
 
 exports.compile = (repo, options) => {
@@ -36,7 +37,8 @@ exports.prepareCompiler = (repo, options) => {
     dashboardTemplateCompilers: [dashboardTemplateEvaluator],
     cubeFactory: cubeSymbols.createCube.bind(cubeSymbols),
     extensions: {
-      Funnels
+      Funnels,
+      RefreshKeys
     }
   }, options));
   return {

packages/cubejs-schema-compiler/extensions/RefreshKeys.js

@@ -0,0 +1,24 @@
+class RefreshKeys {
+  constructor(cubeFactory, compiler) {
+    this.cubeFactory = cubeFactory;
+    this.compiler = compiler;
+    this.immutablePartitionedRollupKey = this.immutablePartitionedRollupKey.bind(this);
+  }
+
+  immutablePartitionedRollupKey(scalarValue) {
+    return {
+      sql: (FILTER_PARAMS) => `SELECT ${this.compiler.contextQuery().caseWhenStatement([{
+        sql: FILTER_PARAMS[
+          this.compiler.contextQuery().timeDimensions[0].path()[0]
+        ][
+          this.compiler.contextQuery().timeDimensions[0].path()[1]
+        ].filter(
+          (from, to) => `${this.compiler.contextQuery().nowTimestampSql()} < ${this.compiler.contextQuery().timeStampCast(to)}`
+        ),
+        label: scalarValue
+      }])}`
+    };
+  }
+}
+
+module.exports = RefreshKeys;