can't connect to browser using go-rod/rod client #1208
Description
Not specifically gomcp issue, but trying to reach Lightpanda Cloud Go support team for go client connection demo code instead.
We tried both chromedp and go-rod, both failed after exhausted trials. Here's only the Go-Rod trial parts.
Support Request: Connecting Go-Rod Client to Lightpanda WSS Endpoint
We are attempting to connect a Go application using the github.com/go-rod/rod library to the Lightpanda Cloud endpoint for browser automation. We are consistently encountering a 400 Bad Request panic during the initial WebSocket handshake, suggesting the authentication token is not being accepted in the expected format.
Environment & Goal
-
Client Library:
github.com/go-rod/rod(Version assumed to be v0.116.2 or recent) -
Target Endpoint:
wss://euwest.cloud.lightpanda.io/ws -
Authentication: Environment variable
LPD_TOKENis set and used. -
Goal: Successfully connect
rod.New().MustConnect()to the endpoint to begin automation.
Error Encountered
The panic is:
panic: websocket bad handshake: 400 Bad request. <html><body><h1>400 Bad request</h1> Your browser sent an invalid request.
</body></html>
This strongly indicates the server is rejecting the connection based on an invalid URL or missing/malformed authentication header.
Full final test code:
package main
import (
"log"
"os"
"time"
"github.com/go-rod/rod"
"github.com/go-rod/rod/lib/launcher"
)
func main() {
// --- 1. Connection Setup ---
lpdToken := os.Getenv("LPD_TOKEN")
if lpdToken == "" {
log.Fatal("LPD_TOKEN environment variable is not set. Please set it.")
}
// Use the WSS URL with the token as the query parameter.
wsURL := "wss://euwest.cloud.lightpanda.io/ws?token=" + lpdToken
log.Printf("Attempting connection via ControlURL: %s", wsURL)
// 2. Resolve the URL string using a standard launcher utility.
// This function is often used to ensure the URL is correctly structured for rod's network client.
u := launcher.MustResolveURL(wsURL)
// 3. Create a rod browser instance using the resolved URL string.
browser := rod.New().
ControlURL(u). // Provide the resolved URL string
Timeout(20 * time.Second).
MustConnect()
defer browser.MustClose()
// --- 4. Automation Task ---
page := browser.MustPage("").MustWaitLoad()
defer page.MustClose()
page.MustNavigate("https://example.com")
title := page.MustInfo().Title
// --- 5. Output the result ---
log.Printf("Successfully connected to Lightpanda Cloud using rod.")
log.Printf("Page Title: %s", title)
}Exhaustive Connection Attempts Made (All Failed)
We have attempted every standard and low-level method provided by the go-rod library, but all resulted in the 400 Bad Request or an "undefined" function error due to package export issues in our installed version.
| Attempt # | Method Used | Code Pattern | Result | Hypothesis/Reason for Failure |
|---|---|---|---|---|
| 1 (Standard) | Token via Query Param | rod.New().ControlURL("wss://.../ws?token=%s").MustConnect() |
400 Bad Request |
Server rejects token in query parameter format. |
| 2 (Low-Level) | External WebSocket (gorilla/websocket) |
Attempted to use websocket.Dial to inject Authorization: Bearer header, then pass to rod.New().Client(conn) |
rod.Client missing required Call method. |
Interface mismatch: *websocket.Conn does not implement rod.CDPClient. |
| 3 (Public API) | Core launcher utilities |
Attempted to use launcher.MustResolveURL or launcher.MustConnectRemote |
Undefined function (MustResolveURL, MustConnectRemote) |
Functions are not publicly exported in the installed go-rod version. |
| 4 (Final Public API) | Core rod functions |
Attempted to use rod.WebSocket(url).Connect() and client.Dial(url) |
Undefined function (rod.WebSocket, client.Dial) |
Functions are not publicly exported in the installed go-rod version. |
Request for Assistance
Since the required low-level API functions in go-rod are not publicly available in our version, and the high-level method is rejected by your server, we require the exact, working Go code snippet for establishing the go-rod connection, specifically handling the authentication for the Lightpanda WSS endpoint.
Please confirm:
-
Should the token be passed as a URL Query Parameter (e.g.,
?token=...)? -
Should the token be passed as an HTTP Header (e.g.,
Authorization: Bearer <token>)? -
If a header is required, what is the exact key and format (e.g.,
Token: <token>orAuthorization: Bearer <token>)?
Thank you for your help in resolving this handshake failure.