Merge pull request #123 from IKatsuba/feature/express-cache

Feature/express cache

apps/rickandmorty/server.ts

@@ -8,13 +8,11 @@ import { join } from 'path';
 import { AppServerModule } from './src/main.server';
 import { APP_BASE_HREF } from '@angular/common';
 import { existsSync } from 'fs';
-import { Request } from 'express';
 import { LRUCache } from '@ngx-ssr/cache';
+import { withCache } from '@ngx-ssr/cache/express';
 
 // The Express app is exported so that it can be used by serverless Functions.
 export function app(): express.Express {
-  const cache = new LRUCache({ maxAge: 10 * 60_000, maxSize: 100 });
-
   const server = express();
   const distFolder = join(process.cwd(), 'dist/apps/rickandmorty/browser');
   const indexHtml = existsSync(join(distFolder, 'index.original.html'))
@@ -24,30 +22,12 @@ export function app(): express.Express {
   // Our Universal express-engine (found @ https://github.com/angular/universal/tree/master/modules/express-engine)
   server.engine(
     'html',
-    async (
-      filePath: string,
-      options: { req: Request },
-      callback: (
-        err?: Error | null | undefined,
-        html?: string | undefined
-      ) => void
-    ) => {
-      const fromCache = await cache.get(options.req.originalUrl).toPromise();
-
-      if (fromCache) {
-        callback(null, fromCache);
-      } else {
-        ngExpressEngine({
-          bootstrap: AppServerModule,
-        })(filePath, options, async (err, html) => {
-          if (!err) {
-            await cache.set(options.req.originalUrl, html).toPromise();
-          }
-
-          callback(err, html);
-        });
-      }
-    }
+    withCache(
+      new LRUCache({ maxAge: 10 * 60_000, maxSize: 100 }),
+      ngExpressEngine({
+        bootstrap: AppServerModule,
+      })
+    )
   );
 
   server.set('view engine', 'html');

libs/ngx-ssr/cache/express/index.ts

@@ -0,0 +1,54 @@
+import { CacheController } from '@ngx-ssr/cache';
+
+export type ExpressRenderEngine = (
+  filePath: string,
+  options: { req: { originalUrl: string }; [key: string]: any },
+  callback: (err?: Error | null | undefined, html?: string | undefined) => void
+) => void;
+
+export function withCache(
+  cache: CacheController,
+  engine: ExpressRenderEngine
+): ExpressRenderEngine {
+  return (
+    filePath: string,
+    options: { req: { originalUrl: string }; [key: string]: any },
+    callback: (
+      err?: Error | null | undefined,
+      html?: string | undefined
+    ) => void
+  ) => {
+    function runEngine() {
+      engine(filePath, options, async (err, html) => {
+        if (!err && originalUrl) {
+          try {
+            await cache.set(originalUrl, html).toPromise();
+          } catch (e) {
+            console.error(`Setting cache for url ${originalUrl} is failed`, e);
+          }
+        }
+
+        callback(err, html);
+      });
+    }
+
+    const originalUrl = options.req?.originalUrl;
+
+    if (!originalUrl) {
+      runEngine();
+      return;
+    }
+
+    cache
+      .get(originalUrl)
+      .toPromise()
+      .then((fromCache) => {
+        if (fromCache) {
+          callback(null, fromCache);
+        } else {
+          runEngine();
+        }
+      })
+      .catch(runEngine);
+  };
+}

libs/ngx-ssr/cache/express/ng-package.json

@@ -0,0 +1,5 @@
+{
+  "lib": {
+    "entryFile": "index.ts"
+  }
+}

libs/ngx-ssr/cache/jest.config.js

@@ -1,7 +1,7 @@
 module.exports = {
   displayName: 'ngx-ssr-cache',
   preset: '../../../jest.preset.js',
-  setupFilesAfterEnv: ['<rootDir>/src/test-setup.ts'],
+  setupFilesAfterEnv: ['<rootDir>/test-setup.ts'],
   globals: {
     'ts-jest': {
       tsConfig: '<rootDir>/tsconfig.spec.json',

libs/ngx-ssr/cache/tsconfig.lib.json

@@ -14,6 +14,7 @@
     "strictMetadataEmit": true,
     "enableResourceInlining": true
   },
-  "exclude": ["src/test-setup.ts", "**/*.spec.ts"],
+  "exclude": [
+    "test-setup.ts", "**/*.spec.ts"],
   "include": ["**/*.ts"]
 }

libs/ngx-ssr/cache/tsconfig.spec.json

@@ -5,6 +5,8 @@
     "module": "commonjs",
     "types": ["jest", "node"]
   },
-  "files": ["src/test-setup.ts"],
+  "files": [
+    "test-setup.ts"
+  ],
   "include": ["**/*.spec.ts", "**/*.d.ts"]
 }

tsconfig.base.json

@@ -16,6 +16,7 @@
     "baseUrl": ".",
     "paths": {
       "@ngx-ssr/cache": ["libs/ngx-ssr/cache/src/index.ts"],
+      "@ngx-ssr/cache/*": ["libs/ngx-ssr/cache/*"],
       "ngx-rickandmorty": ["libs/rickandmorty/api/src/index.ts"],
       "@ngx-ssr/rickandmorty/utils": ["libs/rickandmorty/utils/src/index.ts"],
       "@ngx-ssr/timeout": ["libs/ngx-ssr/timeout/src/index.ts"],