vmod_bodyaccess

Varnish Bodyaccess Module

Author:	Arianna Aondio
Date:	2015-06-18
Version:	1.0

SYNOPSIS

import bodyaccess;

DESCRIPTION

Varnish vmod that lets you access the request body.

FUNCTIONS

len_req_body

Prototype

len_req_body()

Return value

INT

Description

Returns the request body length or -1 if an error occurs.

Note that the request body must be buffered.

Example

| std.cache_req_body(1KB);
| set req.http.x-len = bodyaccess.len_req_body();

hash_req_body

Prototype

hash_req_body()

Return value

VOID

Description

Adds available request body bytes to the lookup hash key. Note that this function can only be used in vcl_hash and the request body must be buffered.

Example

| sub vcl_recv {
|     std.cache_req_body(1KB);
| }
|
| sub vcl_hash{
|     bodyaccess.hash_req_body();
| }

rematch_req_body

Prototype

rematch_req_body(PRIV_CALL, STRING re)

Return value

INT

Description

Returns -1 if an error occurrs. Returns 0 if the request body doesn't contain the string re. Returns 1 if the request body contains the string re.

Note that the comparison is case sensitive and the request body must be buffered.

Example

| std.cache_req_body(1KB);
|
| if (bodyaccess.rematch_req_body("FOO") == 1) {
|    std.log("is true");
| }

req_body

Prototype

req_body()

Return value

STRING

Description

Return available request body to VCL. Note that this function can only be used in vcl_recv and the request body must already be in std buffer. Its intent is for a small body, workspace's storage is used.

Example

| sub vcl_recv {
|     std.cache_req_body(256B);
|
|     set req.http.body = regsub(bodyaccess.req_body(), "foo", "bar");
| }

Find more example in example.vcl.

N.B. The request body must be retrieved before doing any operations on it. It can be buffered using the cache_req_body() function from libvmod_std.

These functions applies only to standard REST methods. Caching is not allowed on PUT requests.

INSTALLATION

The source tree is based on autotools to configure the building, and does also have the necessary bits in place to do functional unit tests using the varnishtest tool.

Building requires the Varnish header files and uses pkg-config to find the necessary paths.

Usage:

./autogen.sh
./configure

If you have installed Varnish to a non-standard directory, call autogen.sh and configure with PKG_CONFIG_PATH pointing to the appropriate path. For example, when varnishd configure was called with --prefix=$PREFIX, use

PKG_CONFIG_PATH=${PREFIX}/lib/pkgconfig export PKG_CONFIG_PATH

Make targets:

• make - builds the vmod.
• make install - installs your vmod.
• make check - runs the unit tests in src/tests/*.vtc
• make distcheck - run check and prepare a tarball of the vmod.

COMMON PROBLEMS

• configure: error: Need varnish.m4 -- see README.rst

  Check if PKG_CONFIG_PATH has been set correctly before calling autogen.sh and configure