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VMOD_H2(3) Library Functions Manual VMOD_H2(3)

NAME

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(1)) 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(1)) 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(1)) 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
are met:
1. Redistributions of source code must retain the above copyright


   notice, this list of conditions and the following disclaimer.
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   notice, this list of conditions and the following disclaimer in the


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