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.. include:: ../../../common.defs

.. default-domain:: c

TSHttpTxnServerIntercept
************************

Intercept origin server requests.

Synopsis
========

`#include <ts/ts.h>`

.. function:: void TSHttpTxnServerIntercept(TSCont contp, TSHttpTxn txnp)

Description
===========

:func:`TSHttpTxnServerIntercept` allows a plugin take over the
servicing of the request as though it was the origin server. In the
event a request needs to be made to the server for transaction
:arg:`txnp`, :arg:`contp` will be sent a :data:`TS_EVENT_NET_ACCEPT`
event. The :arg:`edata` passed with :data:`TS_NET_EVENT_ACCEPT` is
an :type:`TSVConn` just as it would be for a normal accept. The
plugin must act as if it is an HTTP server and read the HTTP request
and body from the :type:`TSVConn` and send an HTTP response header
and body.

:func:`TSHttpTxnServerIntercept` must be not be called after the
connection to the server has taken place. This means that the last
hook that it can be called from is
:data:`TS_HTTP_READ_CACHE_HDR_HOOK`. If a connection to the server
is not necessary, the continuation :arg:`contp` will be sent a
:data:`TS_EVENT_NET_ACCEPT_FAILED` event when the transaction
completes.

The response from the plugin is cached subject to standard and
configured HTTP caching rules. Should the plugin wish the response
not be cached, the plugin must use appropriate HTTP response headers
to prevent caching. The primary purpose of :func:`TSHttpTxnServerIntercept`
is allow plugins to provide gateways to other protocols or to allow
to plugin to its own transport for the next hop to the server.
:func:`TSHttpTxnServerIntercept` overrides parent cache configuration.

:func:`TSHttpTxnServerIntercept` must only be called once per
transaction. The continuation :arg:`contp` must have been created
with a valid :type:`TSMutex`.

See Also
========

:manpage:`TSAPI(3ts)`
