refactor(rest): use on-finished module instead of hand-written solution

loopbackio · Feb 12, 2019 · 49aeac9 · 49aeac9
1 parent 914ad47
commit 49aeac9
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Showing 2 changed files with 11 additions and 6 deletions.
diff --git a/packages/rest/package.json b/packages/rest/package.json
@@ -30,6 +30,7 @@
     "@types/express": "^4.11.1",
     "@types/express-serve-static-core": "^4.16.0",
     "@types/http-errors": "^1.6.1",
+    "@types/on-finished": "^2.3.1",
     "@types/serve-static": "1.13.2",
     "@types/type-is": "^1.6.2",
     "ajv": "^6.5.1",
@@ -40,6 +41,7 @@
     "http-errors": "^1.6.3",
     "js-yaml": "^3.11.0",
     "lodash": "^4.17.11",
+    "on-finished": "^2.3.0",
     "openapi-schema-to-json-schema": "^2.1.0",
     "openapi3-ts": "^1.0.0",
     "path-to-regexp": "^3.0.0",

diff --git a/packages/rest/src/router/static-assets-route.ts b/packages/rest/src/router/static-assets-route.ts
@@ -5,10 +5,12 @@
 
 import {Context} from '@loopback/context';
 import {OperationObject, SchemasObject} from '@loopback/openapi-v3-types';
-import {Router, RequestHandler, static as serveStatic} from 'express';
+import {RequestHandler, Router, static as serveStatic} from 'express';
 import {PathParams} from 'express-serve-static-core';
 import * as HttpErrors from 'http-errors';
+import * as onFinished from 'on-finished';
 import {ServeStaticOptions} from 'serve-static';
+import {promisify} from 'util';
 import {RequestContext} from '../request-context';
 import {
   OperationArgs,
@@ -70,6 +72,8 @@ export class StaticAssetsRoute implements RouteEntry, ResolvedRoute {
   }
 }
 
+const onFinishedAsync = promisify(onFinished);
+
 /**
  * Execute an Express-style callback-based request handler.
  *
@@ -86,11 +90,9 @@ function executeRequestHandler(
   request: Request,
   response: Response,
 ): Promise<boolean> {
-  return new Promise((resolve, reject) => {
-    const onceFinished = () => resolve(true);
-    response.once('finish', onceFinished);
-    handler(request, response, (err: Error) => {
-      response.removeListener('finish', onceFinished);
+  const responseWritten = onFinishedAsync(response).then(() => true);
+  const handlerFinished = new Promise<boolean>((resolve, reject) => {
+    handler(request, response, err => {
       if (err) {
         reject(err);
       } else {
@@ -99,4 +101,5 @@ function executeRequestHandler(
       }
     });
   });
+  return Promise.race([handlerFinished, responseWritten]);
 }