补充一下亚历山大的答案。

默认情况下，NGINX对每个文件的上传限制为1mb。通过限制上传的文件大小，可以防止某些类型的拒绝服务(DOS)攻击和许多其他问题。

因此，当您尝试上传超过1MB限制的文件时，您将遇到413错误。

通过编辑“client_max_body_size”，可以调整上传文件的大小。使用http、server或location块编辑client_max_body_size。

server {
  server_name example.com;

  location / {
    proxy_set_header HOST $host;
    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    proxy_pass http://127.0.0.1:8080;
    client_max_body_size 20M;
  }

    listen [::]:443 ssl ipv6only=on; # managed by Certbot
    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/infohob.com/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/infohob.com/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

参考:在NGINX限制文件上传大小

我正在使用multer上传文件到AWS s3。 对于我来说，在添加client_max_body_size 100M之后;导入nginx文件， 误差是400。(但是413错误消失了，这意味着它成功地通过nginx到达了你的服务器)

解决方案如下: https://stackoverflow.com/a/71240419/15477963

我的app.js文件不需要改变，保持如下所示:

const express = require('express');
const bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));

此问题在两种情况下发生:

请求体太大，服务器无法处理这么大的数据。这个就可以了

app.use(express.json({limit: '50mb'}));

2- req.cookies is too large. When testing different next.js applications on the same browser, each time each app was starting on a different port if there were running some apps. Same app might end up starting at port 3000-3005 range. That means if your app saves cookie, that cookie will be saved for each port. Let's say you started 5 different apps at localhost:3000, and each one saved a cookie. If you make a request, all the cookies will be attached to the request object, in this case you will not able to process even small size of post.body. Solution is you have to delete all the cookies

我也有同样的问题

使用快捷4.+ 我的代码看起来像这样，经过两天的广泛测试，它工作得很好。

var url         = require('url'),
    homePath    = __dirname + '/../',
    apiV1       = require(homePath + 'api/v1/start'),
    bodyParser  = require('body-parser').json({limit:'100mb'});

module.exports = function(app){
    app.get('/', function (req, res) {
        res.render( homePath + 'public/template/index');
    });

    app.get('/api/v1/', function (req, res) {
        var query = url.parse(req.url).query;
        if ( !query ) {
            res.redirect('/');
        }
        apiV1( 'GET', query, function (response) {
            res.json(response);
        });
    });

    app.get('*', function (req,res) {
        res.redirect('/');
    });

    app.post('/api/v1/', bodyParser, function (req, res) {
        if ( !req.body ) {
            res.json({
                status: 'error',
                response: 'No data to parse'
            });
        }
        apiV1( 'POST', req.body, function (response) {
            res.json(response);
        });
    });
};

补充一下亚历山大的答案。

默认情况下，NGINX对每个文件的上传限制为1mb。通过限制上传的文件大小，可以防止某些类型的拒绝服务(DOS)攻击和许多其他问题。

因此，当您尝试上传超过1MB限制的文件时，您将遇到413错误。

通过编辑“client_max_body_size”，可以调整上传文件的大小。使用http、server或location块编辑client_max_body_size。

server {
  server_name example.com;

  location / {
    proxy_set_header HOST $host;
    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    proxy_pass http://127.0.0.1:8080;
    client_max_body_size 20M;
  }

    listen [::]:443 ssl ipv6only=on; # managed by Certbot
    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/infohob.com/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/infohob.com/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

参考:在NGINX限制文件上传大小

更好的使用方法是，你可以指定文件大小的限制，如下所示:

app.use(bodyParser.json({limit: '10mb', extended: true}))
app.use(bodyParser.urlencoded({limit: '10mb', extended: true}))

您也可以在node-modules body-parser中更改默认设置，然后在lib文件夹中，有JSON和文本文件。然后改变这里的极限。实际上，如果你没有在给定的行中传递limit参数，这个条件就会通过 app.use (bodyParser。Json ({limit: '10mb'， extended: true}))。