net::ERR_CONNECTION_CLOSED when Bearer token over 5260 characters.

Hi Team,

I’m using version 3.25. I get a strange issue for one of the users (unfortunately tester). When the user tries to execute API gets the result:

CODE: undocumented; Details: TypeError: Failed to fetch On console, we get: net::ERR_CONNECTION_CLOSED

We are using Bearer Token authorization. The only difference between working user cases and fail is the token. A user on with it fails have many roles stored in the token and the length of the header token is over 5260 chars.

Way to reproduce:

1. Create API with Header Bearer Token authorization.
2. Call API by setting token over 5260 chars length.

There is no issue when the user calls endpoint through curl command or postman.

Example API:

{
  "openapi": "3.0.1",
  "info": {
    "title": "Warehouse API",
    "version": "v1"
  },
  "paths": {
    "/api/test": {
      "get": {
        "tags": [
          "test"
        ],
        "parameters": [ ],
		"responses": {
			"200": {
				"description": "Success"
			}
		}
      },  
	},
  },
  "components": {
	"schemas": {},
    "securitySchemes": {
      "TST-Bearer": {
        "type": "apiKey",
        "description": "JWT Authorization header using the Bearer scheme. Example: \"TST-Authorization: Bearer {token}\"",
        "name": "TST-Authorization",
        "in": "header"
      }
    }
  },
  "security": [
    {
      "TST-Bearer": [
        "readAccess",
        "writeAccess"
      ]
    }
  ]
}

[chunyeow]

After a few round of digging and understanding the issue, this is not relevant to swagger UI instead due to the proxy in front of API server. In our case, we are deploying the ingress controller at Kubernetes cluster that have restriction of http2-max-header-size that causing the “long” request header to be rejected.

[GaetanoPiazzolla]

Nginx does not write anything. It seems that it’s blocked by the browser. Very strange behavior. Anyway with the configuration specified above everything works correctly.