vmod_h2 - Module to control the built-in HTTP2 transport

          Copyright 2023 UPLEX - Nils Goroll Systemoptimierung
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          Author: Nils Goroll <nils.goroll@uplex.de>

          SPDX-License-Identifier: BSD-2-Clause

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                                                                                                      VMOD_H2(3)

       This VMOD contains functions to control the HTTP2 transport built into Varnish-Cache.

   BOOLis()
       Restricted to: client.

       Returns true when called on a session handled by the built-in HTTP2 transport.

   DURATIONrapid_reset([DURATIONthreshold])
       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.

   INTrapid_reset_limit([INTnumber])
       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.

   DURATIONrapid_reset_period([DURATIONduration])
       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.

   REALrapid_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.

       vmod_h2 - Module to control the built-in HTTP2 transport

       • varnishd(1)

       • vsl(7)

          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()