nginx returns Chinese json

The project uses nginx as a proxy. If we encounter a project upgrade, we need to inform the mobile client that the current service is unavailable, and we don't want to create a special project to do this.

Here you can use the nginx configuration to solve this.

location ^~/api/{
    default_type application/json;return200'{"ret":"-1","msg":"request later plz"}';}

When the requested path starts with /api, it will be handled by this.

There may be garbled characters in Chinese in the returned json, and charset and charset_types need to be added.

location ^~/api/{
    charset utf-8;
    charset_types application/json;
    default_type application/json;return200'{"ret":"-1","msg":"系统升级,请稍后访问"}';}