我正在将我的应用迁移到AWS EC2实例上,之前它是托管在Hostgator上,并且一切都运行良好,但现在我已经成功地将其迁移,却遇到了CORS错误的问题。
我的应用程序是一个使用Angular 6构建的前端应用,我使用nginx进行部署。后端托管在Heroku上,是一个NodeJs 8.0的Restful API。
经过多次研究,我发现我需要更改我的应用程序的serve文件。
一开始它是这样的,除了CORS错误之外,一切都正常运行:
server {
listen 80;
listen [::]:80;
server_name http://your-site-name.com;
root /var/www/app-name;
server_tokens off;
index index.html index.htm;
location / {
# First attempt to server request as file, then
# as directory, then fall back to displaying a 404.
try_files $uri $uri/ /index.html =404;
}
}
然后我尝试了一个我发现的解决方案
location / {
if ($request_method = 'OPTIONS') {
add_header 'Access-Control-Allow-Origin' '*';
add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
add_header 'Access-Control-Max-Age' 1728000;
add_header 'Content-Type' 'text/plain; charset=utf-8';
add_header 'Content-Length' 0;
return 204;
}
if ($request_method = 'POST') {
add_header 'Access-Control-Allow-Origin' '*';
add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
}
if ($request_method = 'GET') {
add_header 'Access-Control-Allow-Origin' '*';
add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
}
}
这个方法不起作用,重新加载页面后我收到了一个404未找到nginx错误。下一个解决方案也是同样的情况:
location / {
# Simple requests
if ($request_method ~* "(GET|POST)") {
add_header "Access-Control-Allow-Origin" *;
}
# Preflighted requests
if ($request_method = OPTIONS ) {
add_header "Access-Control-Allow-Origin" *;
add_header "Access-Control-Allow-Methods" "GET, POST, OPTIONS, HEAD";
add_header "Access-Control-Allow-Headers" "Authorization, Origin, X-Requested-With, Content-Type, Accept";
return 200;
}
....
# Handle request
....
最后我尝试了这个:
location / {
dav_methods PUT DELETE MKCOL COPY MOVE;
# Preflighted requestis
if ($request_method = OPTIONS) {
add_header "Access-Control-Allow-Origin" *;
add_header "Access-Control-Allow-Methods" "GET, POST, OPTIONS, HEAD, DELETE";
add_header "Access-Control-Allow-Headers" "Authorization, Origin, X-Requested-With, Content-Type, Accept";
return 200;
}
# CORS WHITELIST EVERYTHING
# This is allowing everything because I am running
# locally so there should be no security issues.
if ($request_method = (GET|POST|OPTIONS|HEAD|DELETE)) {
add_header "Access-Control-Allow-Origin" *;
add_header "Access-Control-Allow-Headers" "Authorization, Origin, X-Requested-With, Content-Type, Accept";
}
try_files $uri $uri/ /index.html$is_args$args;
}
这个最后的解决方案运行良好(即我的应用程序正在加载,且没有出现404错误),但仍然给了我CORS错误。
是的,我在后端启用了CORS,这是我的server.js文件:
require('./config/config.js');
//Requires
const express = require('express')
const colors = require('colors')
const bodyParser = require('body-parser')
const app = express();
//Enable cors
app.use(function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With,
Content-Type, Accept, token");
res.header("Access-Control-Allow-Methods", "POST, GET, PUT, DELETE, OPTIONS");
next();
});
// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
app.use(require("./routes/index"));
//serve
app.listen(process.env.PORT, () => {
console.log(`Listening ${process.env.PORT}. Status:`, 'online'.green)
});
这是我在浏览器控制台中遇到的错误
Access to XMLHttpRequest at
'https://backend.herokuapp.com/inventory/most_sold' from origin
'http://front-end-ip' has been blocked by CORS policy: No 'Access-Control-
Allow-Origin' header is present on the requested resource.
我希望有些人能给我一点指导。
提前感谢。