Feat(medusa, medusa-js, medusa-react): Include sales channels in related queries as an optional expand parameter (#1816)

**What**
- Add `transformQuery` to get endpoints for product, order and cart
  - ensure that the default relations (when getting a singular entity) includes sales channels when enabled
- Add `EmptyQueryParams` class in common types to prevent query parameters while using `transformQuery`
- update product-, order- and cartFactory to include sales channels if provided
- remove `packages/medusa/src/controllers/products/admin-list-products.ts`

**Testing** 
- expands sales channel for single order
- expands sales channels for orders with expand parameter 
- returns single product with sales channel 
- expands sales channels for products with expand parameter
- returns cart with sales channel for single cart

Fixes CORE-293

Co-authored-by: Sebastian Rindom <7554214+srindom@users.noreply.github.com>
Co-authored-by: Adrien de Peretti <25098370+adrien2p@users.noreply.github.com>

packages/medusa/src/utils/feature-flag-decorators.ts

@@ -1,40 +1,59 @@
-import { getConfigFile } from "medusa-core-utils"
+ import { getConfigFile } from "medusa-core-utils"
 import { Column, ColumnOptions, Entity, EntityOptions } from "typeorm"
 import featureFlagsLoader from "../loaders/feature-flags"
 import path from "path"
 import { ConfigModule } from "../types/global"
 import { FlagRouter } from "./flag-router"
 
+ /**
+  * If that file is required in a non node environment then the setImmediate timer does not exists.
+  * This can happen when a client package require a server based package and that one of the import
+  * require to import that file which is using the setImmediate.
+  * In order to take care of those cases, the setImmediate timer will use the one provided by the api (node)
+  * if possible and will provide a mock in a browser like environment.
+  */
+let setImmediate_
+try {
+  setImmediate_ = setImmediate
+} catch (e) {
+  console.warn(
+    "[feature-flag-decorator.ts] setImmediate will use a mock, this happen when this file is required in a browser environment and should not impact you"
+  )
+  setImmediate_ = ((callback: () => void | Promise<void>) => callback())
+}
+
 export function FeatureFlagColumn(
   featureFlag: string,
   columnOptions: ColumnOptions = {}
 ): PropertyDecorator {
-  const featureFlagRouter = getFeatureFlagRouter()
+  return function (target, propertyName) {
+    setImmediate_((): any => {
+      const featureFlagRouter = getFeatureFlagRouter()
 
-  if (!featureFlagRouter.isFeatureEnabled(featureFlag)) {
-    return (): void => {
-      // noop
-    }
+      if (!featureFlagRouter.isFeatureEnabled(featureFlag)) {
+        return
+      }
+
+      Column(columnOptions)(target, propertyName)
+    })
   }
-
-  return Column(columnOptions)
 }
 
 export function FeatureFlagDecorators(
   featureFlag: string,
   decorators: PropertyDecorator[]
 ): PropertyDecorator {
-  const featureFlagRouter = getFeatureFlagRouter()
+  return function (target, propertyName) {
+    setImmediate_((): any => {
+      const featureFlagRouter = getFeatureFlagRouter()
 
-  if (!featureFlagRouter.isFeatureEnabled(featureFlag)) {
-    return (): void => {
-      // noop
-    }
-  }
-  // eslint-disable-next-line @typescript-eslint/ban-types
-  return (target: Object, propertyKey: string | symbol): void => {
-    decorators.forEach((decorator) => {
-      decorator(target, propertyKey)
+      if (!featureFlagRouter.isFeatureEnabled(featureFlag)) {
+        return
+      }
+
+      decorators.forEach((decorator: PropertyDecorator) => {
+        decorator(target, propertyName)
+      })
     })
   }
 }
@@ -44,12 +63,10 @@ export function FeatureFlagEntity(
   name?: string,
   options?: EntityOptions
 ): ClassDecorator {
-  // eslint-disable-next-line @typescript-eslint/ban-types
   return function (target: Function): void {
     target["isFeatureEnabled"] = function (): boolean {
       const featureFlagRouter = getFeatureFlagRouter()
 
-      // const featureFlagRouter = featureFlagsLoader(configModule)
       return featureFlagRouter.isFeatureEnabled(featureFlag)
     }
     Entity(name, options)(target)

packages/medusa/src/utils/get-query-config.ts

@@ -27,14 +27,14 @@ export function getRetrieveConfig<TModel extends BaseEntity>(
 ): FindConfig<TModel> {
   let includeFields: (keyof TModel)[] = []
   if (typeof fields !== "undefined") {
-    includeFields = Array
-      .from(new Set([...fields, "id"]))
-      .map(field => (typeof field === "string") ? field.trim() : field) as (keyof TModel)[]
+    includeFields = Array.from(new Set([...fields, "id"])).map((field) =>
+      typeof field === "string" ? field.trim() : field
+    ) as (keyof TModel)[]
   }
 
   let expandFields: string[] = []
   if (typeof expand !== "undefined") {
-    expandFields = expand.map(expandRelation => expandRelation.trim())
+    expandFields = expand.map((expandRelation) => expandRelation.trim())
   }
 
   return {
@@ -106,7 +106,10 @@ export function prepareListQuery<
       orderBy = { [order]: "ASC" }
     }
 
-    if (queryConfig?.allowedFields?.length && !queryConfig?.allowedFields.includes(orderField)) {
+    if (
+      queryConfig?.allowedFields?.length &&
+      !queryConfig?.allowedFields.includes(orderField)
+    ) {
       throw new MedusaError(
         MedusaError.Types.INVALID_DATA,
         `Order field ${orderField} is not valid`