Nginx映射本地json文件，配置解决浏览器跨域问题，提供前端get请求模拟数据

场景

网络接口返回json格式数据，可以直接在浏览器中访问。

可以在页面上右键另存为json格式文件

怎样在本地使用nginx配置，模拟get接口返回该json文件，使前端使用ajax请求数据时，可以返回该json数据，

并且浏览器还不提示跨域。

注：

博客：
https://blog.csdn.net/badao_liumang_qizhi
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实现

1、下载nginx

http://nginx.org/en/download.html

下载对应的版本并解压，找到conf下的配置文件

2、修改配置文件

修改如下几个地方

修改默认类型为json

http {
    include       mime.types;
    default_type  application/json;

配置别名访问

        location /json/ {
   default_type application/json;
   alias D:/jsonData/;
        }

这个配置的意思是先设置响应的内容格式为application/json;

这里的alias配置方式是请求替代的方式，即/json/的请求就去对应D:/jsonData/目录下去找。

配置跨域问题

  add_header Access-Control-Allow-Origin *;
  add_header Access-Control-Allow-Methods 'GET, POST, OPTIONS';
  add_header Access-Control-Allow-Headers 'DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization';
 
  if ($request_method = 'OPTIONS') {
   return 204;
  }

3、完整示例nginx配置

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/json;

    #log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
    #                  '$status $body_bytes_sent "$http_referer" '
    #                  '"$http_user_agent" "$http_x_forwarded_for"';

    #access_log  logs/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    server {
  add_header Access-Control-Allow-Origin *;
  add_header Access-Control-Allow-Methods 'GET, POST, OPTIONS';
  add_header Access-Control-Allow-Headers 'DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization';
 
  if ($request_method = 'OPTIONS') {
   return 204;
  }
        listen       3000;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location /json/ {
   default_type application/json;
   alias D:/jsonData/;
        }

        #error_page  404              /404.html;

        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }

        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ \.php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ \.php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000;
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #    deny  all;
        #}
    }


    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl;
    #    server_name  localhost;

    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_cache    shared:SSL:1m;
    #    ssl_session_timeout  5m;

    #    ssl_ciphers  HIGH:!aNULL:!MD5;
    #    ssl_prefer_server_ciphers  on;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}

}

4、启动nginx，浏览器中访问

http://localhost:3000/json/migration.json

5、前端jquery发起ajax请求示例

        $.ajax({
            url: 'http://localhost:3000/json/migration.json',
            type: "get",
            dataType: 'json',
            success: function (data) {

            }
        });

6、前端请求效果