After scratching my head a bit, the literal only way I've found to silence these messages is to intercept the log output from the http server: https://play.golang.org/p/v66AEQjrG4H

I don't think this is a reasonable approach to the issue though.

cc @FiloSottile

cc @neild also

@FiloSottile @neild

Just giving this a bump -- is there any plan to remove the log message in the future?

I'm happy to do any leg work, but it's not clear what an acceptable path forward is

I second this, the warning must be dismissable.

I have found a workaround that works imho slightly better than filtering the log message out of the log

type semicolonKey struct{}

func storeRawQuery(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if strings.Contains(r.URL.RawQuery, ";") {
			r2 := r.WithContext(context.WithValue(r.Context(), semicolonKey{}, r.URL.RawQuery))
			h.ServeHTTP(w, r2)
			return
		}
		h.ServeHTTP(w, r)
	})
}

func restoreRawQuery(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		q, ok := r.Context().Value(semicolonKey{}).(string)
		if !ok {
			h.ServeHTTP(w, r)
			return
		}

		r2 := new(http.Request)
		*r2 = *r
		r2.URL = new(url.URL)
		*r2.URL = *r.URL
		r2.URL.RawQuery = q
		h.ServeHTTP(w, r2)
	})
}

func allowQuerySemicolons(h http.Handler) http.Handler {
         h = restoreRawQuery(h)
         h = http.AllowQuerySemicolons(h)
         h = storeRawQuery(h)
	return h
}

see here: https://go.dev/play/p/BcGLSVItJqU

Note this completely circumvents http.AllowQuerySemicolons -- except that it will disable the log message. Use with caution.

In my case, it's currently desirable because replacing ; with & is incredibly undesirable for me, but so is that log message. To give a sense of scope, I have to handle several hundred thousand requests per day containing semicolons...that log message is quite intrusive.

Please allow to disable this warning. In the use case of a proxy server we MUST keep semicolons untouched as they act as delimiters for parameters in ad requests sent to a third-party ad server. If we move to latest Go versions, this would result in billion of warnings flooding our log service provider and reaching our allowed quota.

This was a generally unfortunate situation with no perfect tradeoff. We opted for a log line as there was real potential of breaking people's applications by dropping query parameters and we didn't want to do so silently. It has now been long enough that anyone who needed to be alerted of it has learned about it, or doesn't care. We should just remove the log line.

Change https://go.dev/cl/470315 mentions this issue: net/http: remove warning when parsing a query containing a semicolon

This warning has outlived its usefulness. Let's drop it.

I am curious if this change has been incorporated into a release. I am not exactly sure how to determine if it has made it yet. I am on go1.20.2 and still see the warning.

This change is not yet in any release. It will be in the upcoming 1.21 release.

it's already released and it's existing in Go1.21
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