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INKHttpTxnServerIntercept

Allows a plugin to intercept an HTTP request sent to an origin server and to serve the content in place of the origin server.

Prototype

INKReturnCode INKHttpTxnServerIntercept (INKCont contp, INKHttpTxn txnp)

Arguments

INKCont contp is the continuation that is called to accept the connection.

INKHttpTxn txnp is the current HTTP transaction the plugin wants to intercept.

Description

Enables a plugin to intercept an HTTP request sent to an origin server, and then serve the content in place of the origin server. The origin server is not contacted.

This API should be used in the INK_HTTP_READ_REQUEST_HDR_HOOK hook.

Once INKHttpTxnServerIntercept has been called, the handler of the continuation contp receives an event INK_EVENT_NET_ACCEPT. Note that the continuation passed should not have a NULL mutex; if it does, then an error is returned.

The void *data passed to the handler of the continuation contp is a data of type NetVConnection representing the connection.

Once the vconnection is established, you can use regular vconnection operations (INKVConnRead, INKVConnWrite, etc...).

A typical scenario when using INKHttpTxnServerIntercept is:

  • Call INKHttpTxnServerIntercept from hook INK_HTTP_READ_REQUEST_HDR_HOOK .

  • Get called back on the continuation's handler passed as argument to INKHttpTxnServerIntercept.

  • Get the VC from argument void *data.

  • Use INKVConnRead to get the HTTP header. Note that you will not receive an event INK_VCONN_READ_COMPLETE - you will only receive the event INK_VCONN_READ_READY because the number of characters to read is unknown. You should rely on INKTHttpParser to parse the request and return a status INK_PARSE_DONE when the request is fully-received (escape sequence \r\n\r\n read).

  • Use INKHttpParser to parse the request.

  • Use INKVConnWrite to write the HTTP response.

[Note] Note

The request and response go through the Traffic Server HTTP SM. The request and response can be cached; the request is logged in squid.log.

Returns

INK_SUCCESS if the API is called successfully.

INK_ERROR if an error occurs while calling the API or if an argument is invalid. This error is also returned if the continuation passed has a NULL mutex.