versions
go 1.17
github.com/gin-contrib/cors v1.3.1
github.com/gin-gonic/gin v1.7.7
problem
I run gin REST API server in my subdomain.
React app placed in main domain access to the API server with GET method and POST method, but get cors policy error Access to XMLHttpRequest at 'https://<subdomain>.<domain>.xxx/api/v1/users' from origin 'https://<domain>.xxx' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource..
在网络搜索中，我发现了同样的问题和一些解决方案，但它们在我的情况下不起作用.
Code
所有这些程序都收到了相同的错误.
case 1
package gateway
import (
"log"
"github.com/gin-contrib/cors"
"github.com/gin-gonic/gin"
)
func RunServer() {
r := gin.Default()
r.Use(cors.Default())
api := r.Group("/api")
v1 := api.Group("/v1")
userRouters(v1)
err := r.Run()
if err != nil {
log.Printf("failed to run gateway: %v", err)
}
}
case 2
package gateway
import (
"log"
"time"
"github.com/gin-contrib/cors"
"github.com/gin-gonic/gin"
)
func RunServer() {
r := gin.Default()
r.Use(cors.New(cors.Config{
AllowOrigins: []string{"*"},
AllowMethods: []string{"GET", "POST", "PUT", "DELETE"},
AllowHeaders: []string{"Content-Type"},
AllowCredentials: false,
MaxAge: 12 * time.Hour,
}))
api := r.Group("/api")
v1 := api.Group("/v1")
userRouters(v1)
err := r.Run()
if err != nil {
log.Printf("failed to run gateway: %v", err)
}
}
case 3
Missing Access-Control-Allow-Origin in response header. · Issue #29 · gin-contrib/cors个
package gateway
import (
"log"
"github.com/gin-gonic/gin"
)
func CORS() gin.HandlerFunc {
return func(c *gin.Context) {
c.Writer.Header().Set("Access-Control-Allow-Origin", "*")
c.Writer.Header().Set("Access-Control-Allow-Credentials", "true")
c.Writer.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization, accept, origin, Cache-Control, X-Requested-With")
c.Writer.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS, GET, PUT, DELETE")
if c.Request.Method == "OPTIONS" {
c.AbortWithStatus(204)
return
}
c.Next()
}
}
func RunServer() {
r := gin.Default()
r.Use(CORS())
api := r.Group("/api")
v1 := api.Group("/v1")
userRouters(v1)
err := r.Run()
if err != nil {
log.Printf("failed to run gateway: %v", err)
}
}
preflight from terminal
> curl 'https://alb.skhole.club/api/v1/authz' \
-X 'OPTIONS' \
-H 'authority: alb.skhole.club' \
-H 'accept: */*' \
-H 'accept-language: ja,en-US;q=0.9,en;q=0.8' \
-H 'access-control-request-headers: content-type' \
-H 'access-control-request-method: POST' \
-H 'cache-control: no-cache' \
-H 'origin: https://skhole.club' \
-H 'pragma: no-cache' \
-H 'referer: https://skhole.club/' \
-H 'sec-fetch-dest: empty' \
-H 'sec-fetch-mode: cors' \
-H 'sec-fetch-site: same-site' \
-H 'user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36' \
--compressed -i
HTTP/2 502
server: awselb/2.0
date: Wed, 05 Apr 2023 04:04:13 GMT
content-type: text/html
content-length: 524
<html>
<head><title>502 Bad Gateway</title></head>
<body>
<center><h1>502 Bad Gateway</h1></center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
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<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
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Solved
This is caused by the aws_lb_target_group settings.
I set the protocol HTTPS in the target group even though I gave ACM certificates to only Route 53 and ALB.
I replaced HTTPS with HTTP, and now it works.
