From 7f27f649cca0e928a422aaa6182988087338e435 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9C=A8=E6=9D=89?= <zhmushan@qq.com>
Date: Thu, 12 Dec 2019 13:05:26 +0800
Subject: [PATCH] fix: file_server swallowing permission errors (#3467)

---
 std/http/file_server.ts      |  8 +++-----
 std/http/file_server_test.ts | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/std/http/file_server.ts b/std/http/file_server.ts
index 41aac5e451..e3caae882b 100755
--- a/std/http/file_server.ts
+++ b/std/http/file_server.ts
@@ -6,7 +6,7 @@
 // TODO Add tests like these:
 // https://github.com/indexzero/http-server/blob/master/test/http-server-test.js
 
-const { ErrorKind, cwd, args, stat, readDir, open } = Deno;
+const { ErrorKind, DenoError, cwd, args, stat, readDir, open } = Deno;
 import { posix } from "../path/mod.ts";
 import {
   listenAndServe,
@@ -142,10 +142,7 @@ async function serveDir(
 }
 
 async function serveFallback(req: ServerRequest, e: Error): Promise<Response> {
-  if (
-    e instanceof Deno.DenoError &&
-    (e as Deno.DenoError<Deno.ErrorKind.NotFound>).kind === ErrorKind.NotFound
-  ) {
+  if (e instanceof DenoError && e.kind === ErrorKind.NotFound) {
     return {
       status: 404,
       body: encoder.encode("Not found")
@@ -297,6 +294,7 @@ listenAndServe(
         response = await serveFile(req, fsPath);
       }
     } catch (e) {
+      console.error(e.message);
       response = await serveFallback(req, e);
     } finally {
       if (CORSEnabled) {
diff --git a/std/http/file_server_test.ts b/std/http/file_server_test.ts
index f725b32a20..85785d923e 100644
--- a/std/http/file_server_test.ts
+++ b/std/http/file_server_test.ts
@@ -93,3 +93,29 @@ test(async function serveFallback(): Promise<void> {
     killFileServer();
   }
 });
+
+test(async function servePermissionDenied(): Promise<void> {
+  const deniedServer = Deno.run({
+    args: [Deno.execPath(), "run", "--allow-net", "http/file_server.ts"],
+    stdout: "piped",
+    stderr: "piped"
+  });
+  const reader = new TextProtoReader(new BufReader(deniedServer.stdout!));
+  const errReader = new TextProtoReader(new BufReader(deniedServer.stderr!));
+  const s = await reader.readLine();
+  assert(s !== Deno.EOF && s.includes("server listening"));
+
+  try {
+    await fetch("http://localhost:4500/");
+    assertEquals(
+      await errReader.readLine(),
+      "run again with the --allow-read flag"
+    );
+  } catch (e) {
+    throw e;
+  } finally {
+    deniedServer.close();
+    deniedServer.stdout!.close();
+    deniedServer.stderr!.close();
+  }
+});