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CORS pre-flight OPTIONS not working because of lowercase casting

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评估

难度
3/5
预计耗时
1-2 天
新手友好度
35/100
Issue 类型
缺陷
描述清晰度
基本清楚
活跃度
停滞
技术栈
aws, javascript, node.js
领域
api, backend, cloud

调研方向

首先,使用提供的 api.options("/*", ...) 路由重现 OPTIONS 请求,并检查 lambda-api 如何返回已配置的 CORS 标头。跟踪负责将响应标头转换为小写的处理逻辑,然后在 Chrome 中并使用 Postman 验证修正后的预检响应。

由索引模型根据 Issue 内容生成。

描述

Hi all,

I just picked up lambda-api, and seems like its the perfect solution for my project; however, I have been struggling for hours trying to get CORS to work.

My OPTIONS pre-flight request headers are being properly sent, but they're all lower case, and it's causing my web appl running in Google Chrome to not recognize it as Access-Control-Allow-Origin as this is the error I am receiving from it:

Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

I verified, with postman, that this is the headers coming back from the pre-flight OPTIONS request:

image

However, noticed that they're all lower case, and thus Google Chrome cannot find Access-Control-Allow-Origin

This is how it's getting received in Google Chrome:
image

This is how I am providing CORS in my Lambda:

// import AWS Lambda types
import { APIGatewayProxyEventV2, Context } from "aws-lambda";
// import Lambda API default function
import createAPI from "lambda-api";
import { Authorizer, Role } from "./authorizer";
import { ListProducts } from "./products/List";

// instantiate framework
const api = createAPI({});

// ************************************* CORS *************************************
api.options("/*", (req: any, res: any) => {
  // Add CORS headers
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Methods", "*");
  res.header("Access-Control-Allow-Headers", "Content-Type, Authorization, Content-Length, X-Requested-With");
  res.sendStatus(200);
});

Please suggest a workaround for current version of Chrome.

Thank you!

主要语言
JavaScript
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PR 合并指标
30 天内没有已合并 PR

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  3. Fork 仓库,在一个分支上完成修改。
  4. 提交 Pull Request,并在描述里引用这个 Issue 编号。

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