VMOD h2 - Module to control the built-in HTTP2 transport¶
SYNOPSIS¶
import h2 [as name] [from "path"] BOOL is() DURATION rapid_reset([DURATION threshold]) INT rapid_reset_limit([INT number]) DURATION rapid_reset_period([DURATION duration]) REAL rapid_reset_budget()
DESCRIPTION¶
This VMOD contains functions to control the HTTP2 transport built into Varnish-Cache.
BOOL is()¶
Restricted to: client.
Returns true when called on a session handled by the built-in HTTP2 transport.
DURATION rapid_reset([DURATION threshold])¶
Restricted to: client.
Get and optionally set the h2_rapid_reset parameter (See
varnishd) for this HTTP2 session only.
Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.
If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.
INT rapid_reset_limit([INT number])¶
Restricted to: client.
Get and optionally set the h2_rapid_reset_limit parameter (See
varnishd) for this HTTP2 session only.
Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.
If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.
DURATION rapid_reset_period([DURATION duration])¶
Restricted to: client.
Get and optionally set the h2_rapid_reset_period parameter (See
varnishd) for this HTTP2 session only.
Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.
If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.
REAL rapid_reset_budget()¶
Restricted to: client.
Return how many RST frames classified as “rapid” the client is still allowed to send before the session is going to be closed.
SEE ALSO¶
COPYRIGHT¶
Copyright 2023 UPLEX - Nils Goroll Systemoptimierung
All rights reserved.
Author: Nils Goroll <nils.goroll@uplex.de>
SPDX-License-Identifier: BSD-2-Clause
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modification, are permitted provided that the following conditions
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notice, this list of conditions and the following disclaimer.
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