only allow first level properties to be promises

ardatan · Sep 29, 2021 · e619b78 · e619b78
1 parent 9aa2d88
commit e619b78
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Showing 2 changed files with 62 additions and 19 deletions.
diff --git a/packages/stitching-directives/src/properties.ts b/packages/stitching-directives/src/properties.ts
@@ -39,6 +39,31 @@ export function getProperty(object: Record<string, any>, path: Array<string>): a
   return getProperty(prop, newPath);
 }
 
+export function getProperties(object: Record<string, any>, propertyTree: PropertyTree): any {
+  if (object == null) {
+    return object;
+  }
+
+  const newObject = Object.create(null);
+
+  for (const key in propertyTree) {
+    const subKey = propertyTree[key];
+
+    if (subKey == null) {
+      newObject[key] = object[key];
+      continue;
+    }
+
+    const prop = object[key];
+
+    newObject[key] = deepMap(prop, function deepMapFn(item) {
+      return getProperties(item, subKey);
+    });
+  }
+
+  return newObject;
+}
+
 // c.f. https://github.com/graphql/graphql-js/blob/main/src/jsutils/promiseForObject.ts
 export function getResolvedPropertiesOrPromise(
   object: Record<string, any>,
@@ -60,13 +85,9 @@ export function getResolvedPropertiesOrPromise(
           return;
         }
 
-        return deepMap(value, function deepMapFn(item) {
-          return getResolvedPropertiesOrPromise(item, subKey).resolve();
-        })
-          .then(mappedValue => {
-            newObject[key] = mappedValue;
-          })
-          .resolve();
+        newObject[key] = deepMap(value, function deepMapFn(item) {
+          return getProperties(item, subKey);
+        });
       })
     )
   ).then(() => newObject);
@@ -80,16 +101,10 @@ export function propertyTreeFromPaths(paths: Array<Array<string>>): PropertyTree
   return propertyTree;
 }
 
-function deepMap(arrayOrItem: any, fn: (item: any) => any | Promise<any>): ValueOrPromise<any> {
+function deepMap(arrayOrItem: any, fn: (item: any) => any): any {
   if (Array.isArray(arrayOrItem)) {
-    return ValueOrPromise.all(
-      arrayOrItem.map(nestedArrayOrItem =>
-        new ValueOrPromise(() => nestedArrayOrItem).then(resolvedNestedArrayOrItem =>
-          deepMap(resolvedNestedArrayOrItem, fn).resolve()
-        )
-      )
-    );
+    return arrayOrItem.map(nestedArrayOrItem => deepMap(nestedArrayOrItem, fn));
   }
 
-  return new ValueOrPromise(() => fn(arrayOrItem));
+  return fn(arrayOrItem);
 }
diff --git a/packages/stitching-directives/tests/properties.test.ts b/packages/stitching-directives/tests/properties.test.ts
@@ -1,4 +1,4 @@
-import { addProperty, getResolvedPropertiesOrPromise } from "../src/properties";
+import { addProperty, getProperties, getResolvedPropertiesOrPromise } from "../src/properties";
 
 describe('addProperty', () => {
   test('can add a key to an object', () => {
@@ -28,13 +28,41 @@ describe('addProperty', () => {
   });
 });
 
+describe('getProperties', () => {
+  test('can getProperties', async () => {
+    const object = {
+      field1: 'value1',
+      field2: {
+        subfieldA: 'valueA',
+        subfieldB: 'valueB',
+      },
+    }
+
+    const extracted = getProperties(object, {
+      field1: null,
+      field2: {
+        subfieldA: null,
+      }
+    });
+
+    const expectedExtracted = {
+      field1: 'value1',
+      field2: {
+        subfieldA: 'valueA',
+      }
+    }
+
+    expect(extracted).toEqual(expectedExtracted);
+  });
+});
+
 describe('getResolvedPropertiesOrPromise', () => {
   test('can getResolvedPropertiesOrPromise', async () => {
     const object = {
       field1: 'value1',
       field2: Promise.resolve({
-        subfieldA: Promise.resolve('valueA'),
-        subfieldB: Promise.resolve('valueB'),
+        subfieldA: 'valueA',
+        subfieldB: 'valueB',
       }),
     }