Merge branch 'blam/react-router' of github.com:spotify/backstage into blam/react-router

* 'blam/react-router' of github.com:spotify/backstage:
  chore(catalog/swr): Removing superfluous import for useEffect
  feat(catalog/swr): simplify the code significantly. now we are talking. this library is the nutz
  feat(catalog/swr): Added a nice stale-while-revalidate pattern for fetching data
  chore(swr): Updating the yarn.lock

plugins/catalog/package.json

@@ -30,12 +30,12 @@
     "@material-ui/core": "^4.9.1",
     "@material-ui/icons": "^4.9.1",
     "@material-ui/lab": "4.0.0-alpha.45",
-    "node-cache": "^5.1.1",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",
     "react-router": "^6.0.0-alpha.5",
     "react-router-dom": "^6.0.0-alpha.5",
-    "react-use": "^14.2.0"
+    "react-use": "^14.2.0",
+    "swr": "^0.2.2"
   },
   "devDependencies": {
     "@backstage/cli": "^0.1.1-alpha.7",

plugins/catalog/src/api/CatalogClient.ts

@@ -19,14 +19,9 @@ import {
   Location,
   LOCATION_ANNOTATION,
 } from '@backstage/catalog-model';
-import Cache from 'node-cache';
 import { CatalogApi, EntityCompoundName } from './types';
 
 export class CatalogClient implements CatalogApi {
-  // TODO(blam): This cache is just temporary until we have GraphQL.
-  // And client side caching using things like React Apollo or Relay.
-  // There's a lot of loading states that cause flickering around the app which aren't needed.
-  private cache: Cache;
   private apiOrigin: string;
   private basePath: string;
 
@@ -39,7 +34,6 @@ export class CatalogClient implements CatalogApi {
   }) {
     this.apiOrigin = apiOrigin;
     this.basePath = basePath;
-    this.cache = new Cache({ stdTTL: 10 });
   }
 
   private async getRequired(path: string): Promise<any> {
@@ -79,11 +73,6 @@ export class CatalogClient implements CatalogApi {
   async getEntities(
     filter?: Record<string, string | string[]>,
   ): Promise<Entity[]> {
-    const cachedValue = this.cache.get<Entity[]>(
-      `get:${JSON.stringify(filter)}`,
-    );
-    if (cachedValue) return cachedValue;
-
     let path = `/entities`;
     if (filter) {
       const params = new URLSearchParams();

plugins/catalog/src/components/CatalogPage/CatalogPage.tsx

@@ -35,7 +35,6 @@ import Star from '@material-ui/icons/Star';
 import StarOutline from '@material-ui/icons/StarBorder';
 import React, { FC, useCallback, useState } from 'react';
 import { Link as RouterLink } from 'react-router-dom';
-import { useAsync } from 'react-use';
 import { catalogApiRef } from '../..';
 import { defaultFilter, entityFilters, filterGroups } from '../../data/filters';
 import { findLocationForEntityMeta } from '../../data/utils';
@@ -45,6 +44,7 @@ import {
   CatalogFilterItem,
 } from '../CatalogFilter/CatalogFilter';
 import { CatalogTable } from '../CatalogTable/CatalogTable';
+import useStaleWhileRevalidate from 'swr';
 
 const useStyles = makeStyles(theme => ({
   contentWrapper: {
@@ -61,20 +61,21 @@ const useStyles = makeStyles(theme => ({
 
 export const CatalogPage: FC<{}> = () => {
   const catalogApi = useApi(catalogApiRef);
-  const {
-    starredEntities,
-    toggleStarredEntity,
-    isStarredEntity,
-  } = useStarredEntities();
+  const { toggleStarredEntity, isStarredEntity } = useStarredEntities();
+
   const [selectedFilter, setSelectedFilter] = useState<CatalogFilterItem>(
     defaultFilter,
   );
 
-  const { value, error, loading } = useAsync(async () => {
-    const filter = entityFilters[selectedFilter.id];
-    const all = await catalogApi.getEntities();
-    return all.filter(e => filter(e, { isStarred: isStarredEntity(e) }));
-  }, [selectedFilter.id, starredEntities.size]);
+  const { data: entities, error } = useStaleWhileRevalidate(
+    ['catalog/all', entityFilters[selectedFilter.id]],
+    async () => catalogApi.getEntities(),
+  );
+
+  const data =
+    entities?.filter(e =>
+      entityFilters[selectedFilter.id](e, { isStarred: isStarredEntity(e) }),
+    ) ?? [];
 
   const onFilterSelected = useCallback(
     selected => setSelectedFilter(selected),
@@ -195,8 +196,8 @@ export const CatalogPage: FC<{}> = () => {
           </div>
           <CatalogTable
             titlePreamble={selectedFilter.label}
-            entities={value || []}
-            loading={loading}
+            entities={data || []}
+            loading={!data && !error}
             error={error}
             actions={actions}
           />

yarn.lock

@@ -6204,11 +6204,6 @@ clone-response@^1.0.2:
   dependencies:
     mimic-response "^1.0.0"
 
-clone@2.x:
-  version "2.1.2"
-  resolved "https://registry.npmjs.org/clone/-/clone-2.1.2.tgz#1b7f4b9f591f1e8f83670401600345a02887435f"
-  integrity sha1-G39Ln1kfHo+DZwQBYANFoCiHQ18=
-
 clone@^1.0.2:
   version "1.0.4"
   resolved "https://registry.npmjs.org/clone/-/clone-1.0.4.tgz#da309cc263df15994c688ca902179ca3c7cd7c7e"
@@ -13254,13 +13249,6 @@ nocache@2.1.0:
   resolved "https://registry.npmjs.org/nocache/-/nocache-2.1.0.tgz#120c9ffec43b5729b1d5de88cd71aa75a0ba491f"
   integrity sha512-0L9FvHG3nfnnmaEQPjT9xhfN4ISk0A8/2j4M37Np4mcDesJjHgEUfgPhdCyZuFI954tjokaIj/A3NdpFNdEh4Q==
 
-node-cache@^5.1.1:
-  version "5.1.1"
-  resolved "https://registry.npmjs.org/node-cache/-/node-cache-5.1.1.tgz#5fcc887176b23bdcd19cd1461b9544d2d501e786"
-  integrity sha512-bJ9nH25Z51HG2QIu66K4dMVyMs6o8bNQpviDnXzG+O/gfNxPU9IpIig0j4pzlO707GcGZ6QA4rWhlRxjJsjnZw==
-  dependencies:
-    clone "2.x"
-
 node-cleanup@^2.1.2:
   version "2.1.2"
   resolved "https://registry.npmjs.org/node-cleanup/-/node-cleanup-2.1.2.tgz#7ac19abd297e09a7f72a71545d951b517e4dde2c"
@@ -17706,6 +17694,13 @@ svgo@^1.0.0, svgo@^1.2.2:
     unquote "~1.1.1"
     util.promisify "~1.0.0"
 
+swr@^0.2.2:
+  version "0.2.2"
+  resolved "https://registry.npmjs.org/swr/-/swr-0.2.2.tgz#6e1b3e5c0e545c4fdb36ae3aa38cd94d0f9a88b7"
+  integrity sha512-D/z+PTUchZhoUA0tNC8TNJivf7Hc61WPxbUdXPi+VxRloddWYNP1ZicaEgyAph42ZnKl1L7twcZr4q6d0UMXcg==
+  dependencies:
+    fast-deep-equal "2.0.1"
+
 symbol-observable@^1.1.0, symbol-observable@^1.2.0:
   version "1.2.0"
   resolved "https://registry.npmjs.org/symbol-observable/-/symbol-observable-1.2.0.tgz#c22688aed4eab3cdc2dfeacbb561660560a00804"