feat(nestjs): add nestjs interceptor

Author: ecyrbe

README.md

@@ -41,7 +41,7 @@ or
 yarn add stalier
 ```
 
-## USAGE
+## USAGE : Express
 
 Stalier do not provide a cache on it's own, nor does it provide a logger. But you provide them both in the constructor.
 
@@ -119,6 +119,28 @@ app.use(stalier({
 }));
 ```
 
+## USAGE : NestJS
+
+Stalier uses the `NestJsInterceptor` to intercept the request and response, and uses the Cache Module to cache the response.
+
+```typescript
+// declare a fake controller to test the interceptor
+@UseStalierInterceptor({ appName: 'myApp' })
+@Controller()
+class MyAppController {
+  @Get('/default-kay')
+  getDefaultKey() {
+    return { hello: 'world' };
+  }
+
+  @UseCacheKeyGen(() => 'test')
+  @Get('/custom-key')
+  getCustomKey() {
+    return { hello: 'world' };
+  }
+}
+```
+
 ## Header `x-stalier-cache-control` params
 
 Stalier is using the `x-stalier-cache-control` header to control the cache behaviour.

package.json

@@ -28,20 +28,29 @@
     "test": "jest --coverage"
   },
   "devDependencies": {
+    "@nestjs/common": "9.0.7",
+    "@nestjs/core": "9.0.7",
+    "@nestjs/platform-express": "^9.0.7",
+    "@nestjs/testing": "9.0.7",
+    "@types/cache-manager": "^4.0.1",
     "@types/express": "4.17.13",
     "@types/jest": "28.1.6",
     "@types/node": "18.0.1",
     "@types/supertest": "2.0.12",
     "@typescript-eslint/eslint-plugin": "5.31.0",
     "@typescript-eslint/parser": "5.31.0",
+    "cache-manager": "^4.1.0",
     "eslint": "8.20.0",
     "eslint-config-prettier": "8.5.0",
     "express": "4.18.1",
     "jest": "28.1.3",
     "prettier": "2.7.1",
+    "reflect-metadata": "0.1.13",
+    "rxjs": "7.5.6",
     "supertest": "6.2.4",
     "ts-jest": "28.0.7",
     "ts-node": "10.9.1",
     "typescript": "4.7.4"
-  }
+  },
+  "dependencies": {}
 }

src/common/constants.ts

@@ -1,3 +1,5 @@
 export const STALIER_HEADER_KEY = 'X-Stalier-Cache-Control';
+export const STALIER_APP_NAME = 'STALIER_APP_NAME';
+export const STALIER_CACHE_KEY_GEN = 'STALIER_CACHE_KEY_GEN';
 
 export const MATCH_HEADER = /s-maxage=([0-9]+)(\s*,\s*(stale-while-revalidate=([0-9]+)))?/;

src/common/utils.ts

@@ -4,5 +4,5 @@ import { Request } from 'express';
  * default cache key generator
  */
 export const defaultKeyGenerator = (name: string) => (req: Request) => {
-  return `${name}-${req.method}-${req.originalUrl}`;
+  return `${name}-${req.method}-${req.originalUrl.replace(/[._~:/?#[\]@!$&'()*+,;=]/g, '')}`;
 };

src/nestjs/decorators.ts

@@ -0,0 +1,13 @@
+import { applyDecorators, UseInterceptors, SetMetadata } from '@nestjs/common';
+import { Request } from 'express';
+import { STALIER_APP_NAME, STALIER_CACHE_KEY_GEN } from '../common/constants';
+import { StalierInterceptor } from './interceptor';
+
+export const UseStalierInterceptor = (options: { appName: string; cacheKeyGen?: (req: Request) => string }) =>
+  applyDecorators(
+    SetMetadata(STALIER_APP_NAME, options.appName),
+    SetMetadata(STALIER_CACHE_KEY_GEN, options.cacheKeyGen),
+    UseInterceptors(StalierInterceptor),
+  );
+
+export const UseCacheKeyGen = (keyGen: (req: Request) => string) => SetMetadata(STALIER_CACHE_KEY_GEN, keyGen);