谁能解释一下为什么 "curl: (7) Failed to connect to 127.0.0.1 port 2000: Connection refused"？

Question

我不明白为什么说 "curl: (7) Failed to connect to 127.0.0.1 port 2000: Connection refused" :

curl -X POST -F 'first_name=pinco' -F 'last_name=pallo' -F 'company_name=Company' -F 
'email=pinco.pallo@company.com' -F 'tel=111111111' 127.0.0.1:2000/puser/add curl: (7) Failed
to connect to 127.0.0.1 port 2000: Connection refused.

在服务器中-gorillamux.go：

CONN_PORT = "2000"

在 /etc/nginx/conf.d/default.conf :

upstream golang-webserver {
    ip_hash;
    server 127.0.0.1:2000;
}

server {
    #listen 2999;
    server_name ggc.world;

    root /puser/add; // Is this correct?

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers EECDH+CHACHA20:EECDH+CHACHA20-draft:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DES:!MD5;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:50m;

    location / {
        #proxy_pass http://127.0.0.1:8080;
        proxy_pass http://golang-webserver;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        #proxy_set_header Host $host;
    }
}

这是 ggc/goServer/server-gorillamux.go :

package main

import (
        "encoding/json"
        "github.com/gorilla/mux"
        "log"
        "net/http"
)

const (
        CONN_HOST = "192.168.1.7"
        CONN_PORT = "2000"
)

type Puser struct {
        first_name   string `json:"first_name"`
        last_name    string `json:"last_name"`
        country      string `json:"country"`
        company_name string `json:"company_name"`
        email        string `json:"email"`
        tel          string `json:"tel"`
}

type Pusers []Puser
var pusers []Puser

type Route struct {
        Name        string
        Method      string
        Pattern     string
        HandlerFunc http.HandlerFunc
}

type Routes []Route

var routes = Routes{
        Route{
                "getPusers",
                "GET",
                "/pusers",
                getPusers,
        },
        Route{
                "addPuser",
                "POST",
                "/puser/add",
                addPuser,
        },
}


func getPusers(w http.ResponseWriter, r *http.Request) {
        json.NewEncoder(w).Encode(pusers)
}

func addPuser(w http.ResponseWriter, r *http.Request) {
        puser := Puser{}
        err := json.NewDecoder(r.Body).Decode(&puser)
        if err != nil {
                log.Print("error occured while decoding puser data 
:: ", err)
        }
        log.Printf("adding puser id :: % s with firstName ass :: %s 
and lastName as :: %s ", puser.first_name, puser.last_name)
        pusers = append(pusers, Puser{first_name: puser.first_name,
            last_name: puser.last_name, country: puser.country, 
company_name: puser.company_name,
                email: puser.email, tel: puser.tel})
        json.NewEncoder(w).Encode(pusers)
}

func AddRoutes(router *mux.Router) *mux.Router {
        for _, route := range routes {
                router.
                        Methods(route.Method).
                        Path(route.Pattern).
                        Name(route.Name).
                        Handler(route.HandlerFunc)
        }
        return router
}

func main() {
        muxRouter := mux.NewRouter().StrictSlash(true)
        router := AddRoutes(muxRouter)
        router.PathPrefix("/").Handler(http.FileServer(http.Dir("..
/src/components/auth/Forms.vue"))) 

        err := http.ListenAndServe(CONN_HOST+":"+CONN_PORT, router)
        if err != nil {
                log.Fatal("error starting http server :: ", err)
                return
        }
}

这是完整的 /etc/nginx/conf.d/default.conf :

server {
    listen 443 ssl http2 default_server;
    server_name ggc.world;
    ssl_certificate /etc/letsencrypt/live/ggc.world-
0002/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/ggc.world-   
0002/privkey.pem; # managed by Certbot

    ssl_trusted_certificate /etc/letsencrypt/live/ggc.world
/chain.pem;

    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by 
Certbot

    ssl_session_timeout 5m;
    #ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers EECDH+CHACHA20:EECDH+CHACHA20-
draft:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DE
S:!MD5;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:50m;
    #ssl_stapling on;
    #ssl_stapling_verify on;

    access_log /var/log/nginx/ggcworld-access.log combined;

    add_header Strict-Transport-Security "max-age=31536000";
    location = /favicon.ico { access_log off; log_not_found off; }

    location / {
        proxy_pass http://127.0.0.1:8080;
        #proxy_pass http://127.0.0.1:2000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        #proxy_set_header Host $host;
    }

    location /weights {
      #sendfile on;
      #tcp_nopush on;
      try_files $uri $uri/ /home/marco/webMatters/vueMatters
/ggc/src/components/auth/weights/;
      proxy_pass http://127.0.0.1:9091/weights/;
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header Host $host;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      # Following is necessary for Websocket support
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection "upgrade";
    }

}

server {
    if ($host = ggc.world) {
        return 301 https://$host$request_uri;
    } # managed by Certbot


    listen 80 default_server;
    listen [::]:80 default_server;
    error_page 497 https://$host:$server_port$request_uri;
    server_name ggc.world;
    return 301 https://$server_name$request_uri;

    access_log /var/log/nginx/ggcworld-access.log combined;

    add_header Strict-Transport-Security "max-age=31536000";
    location = /favicon.ico { access_log off; log_not_found off; }

    location / {
        proxy_pass http://127.0.0.1:8080;
        #proxy_pass http://127.0.0.1:2000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        #proxy_set_header Host $host;
    }
}

upstream websocket {
    ip_hash;
    server localhost:3000;
}

server {
    listen 81;
    server_name ggc.world;

    location ~ ^/(websocket|websocket\/socket-io) {
        proxy_pass http://127.0.0.1:4201;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header X-Forwared-For $remote_addr;
        proxy_set_header Host $host;

        proxy_redirect off;
        proxy_set_header X-Real-IP $remote_addr;
    }
}

upstream golang-webserver {
    ip_hash;
    server 127.0.0.1:2000;
}

server {
    #listen 2999;
    server_name ggc.world;

    root /puser/add;

    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers EECDH+CHACHA20:EECDH+CHACHA20-
  draft:EECDH+AES128:RSA+AES128:EECDH+AES256:RSA+AES256:EECDH+3DES:RSA+3DE
S:!MD5;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:50m;

    location / {
        proxy_pass http://golang-webserver;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        #proxy_set_header Host $host;
    }
}

已在 Internet 服务提供商配置中为 TCP 和 UDP 打开端口 2000。

更新 1)

放入服务器后-gorillamux.go CONN_HOST = "127.0.0.1" 错误类型已更改：

curl -X POST -F 'first_name=pinco' -F 'last_name=pallo' -F   
'company_name=Company'  -F 'email=pinco.pallo@company.com' -F  
'tel=111111111' http://127.0.0.1:2000/puser/add
[{}]


go run ./server-gorillamux.go
2020/05/13 12:24:55 error occured while decoding puser data :: invalid
character '-' in numeric literal
2020/05/13 12:24:55 adding puser id ::  with firstName ass ::  and 
lastName as :: %!s(MISSING)

更新 2)

curl --verbose -X POST -d'{"first_name":"pinco", "last_name":"pallo", 
"company_name":"Company","email":"pinco.pallo@company.com","tel":"11111111
1"}' 127.0.0.1:2000/puser/add
Note: Unnecessary use of -X or --request, POST is already inferred.
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to 127.0.0.1 (127.0.0.1) port 2000 (#0)
> POST /puser/add HTTP/1.1
> Host: 127.0.0.1:2000
> User-Agent: curl/7.58.0
> Accept: */*
> Content-Length: 121
> Content-Type: application/x-www-form-urlencoded
> 
* upload completely sent off: 121 out of 121 bytes
< HTTP/1.1 200 OK
< Date: Wed, 13 May 2020 11:01:00 GMT
< Content-Length: 8
< Content-Type: text/plain; charset=utf-8
< 
[{},{}]
* Connection #0 to host 127.0.0.1 left intact

go run ./server-gorillamux.go
2020/05/13 13:01:00 adding puser id ::  with firstName ass ::  and 
lastName as :: %!s(MISSING)

更新 3：

将每个字段的首字母大写使 json 可以看到它们，但每个字段的值尚未导出。 addPuser 函数中必须有一些要修复的东西：

curl -X POST -F 'first_name=pinco' -F 'last_name=pallo' -F 
'company_name=Company'  -F 'email=pinco.pallo@company.com' -F  
'tel=111111111' http://127.0.0.1:2000/puser/add
    [{"First_name":"","Last_name":"","Country":"","Company_name":"","Email":""
,"Tel":""}]  o run ./server-gorillamux.go
2020/05/13 13:27:03 error occured while decoding puser data :: invalid
character '-' in numeric literal
2020/05/13 13:27:03 adding puser id ::  with firstName as :: , 
lastName as :: , country as :: $s,companyName as :: , email as :: , 
tel as::

期待您的帮助。马可

Answer 1

Purser 字段未导出，因此 JSON 解码器看不到它们，您需要将它们大写以解决此问题：

type Puser struct {
        FirstName    string `json:"first_name"`
        LastName     string `json:"last_name"`
        Country      string `json:"country"`
        CompanyName  string `json:"company_name"`
        Email        string `json:"email"`
        Tel          string `json:"tel"`
}

然后，你也发出了错误的请求，在表单数据中发送参数，而不是在请求正文中发送 JSON 对象，如下所示：

curl -X POST -d'{"first_name":"pinco", "last_name":"pallo", "company_name":"Company","email":"pinco.pallo@company.com","tel":"111111111"}' 127.0.0.1:2000/puser/add

谁能解释一下为什么 "curl: (7) Failed to connect to 127.0.0.1 port 2000: Connection refused"？

Can someone explain me why "curl: (7) Failed to connect to 127.0.0.1 port 2000: Connection refused"?

nginx

go

nginx-reverse-proxy

nginx-config