---
name: "vmod_bodyaccess"
section: "3"
platform: "linux"
package: "varnish-modules"
version: "0.25.0-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/vmod_bodyaccess"
---

# vmod\_bodyaccess(3)

Varnish Module for request body access

## NAME

vmod\_bodyaccess - Varnish Module for request body access

## SYNOPSIS

```
import bodyaccess [as name] [from "path"]
INT rematch_req_body(REGEX re)
VOID hash_req_body()
INT len_req_body()
VOID log_req_body(STRING prefix, INT length)
```

## DESCRIPTION

Varnish module that lets you access the request body.

VCL example:

```
vcl 4.0;
import std;
import bodyaccess;
backend default { .host = "192.0.2.11"; .port = "8080"; }
sub vcl_recv {
        if (req.method == "POST") {
                set req.http.x-method = req.method;
                if (std.cache_req_body(110KB)) {
                        set req.http.x-len = bodyaccess.len_req_body();
                        set req.http.x-re = bodyaccess.rematch_req_body("Regex");
                        bodyaccess.log_req_body("PREFIX:", 3);
                }
        }
return(hash);
}
sub vcl_hash {
        bodyaccess.hash_req_body();
        return (lookup);
}
sub vcl_backend_fetch {
        set bereq.method = bereq.http.x-method;
}
sub vcl_deliver {
        set resp.http.x-len = req.http.x-len;
        set resp.http.x-re = req.http.x-re;
}
```

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.

### INT rematch\_req\_body(REGEX re)

- **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");
  | }
  ```

### VOID hash\_req\_body()

- **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();
  | }
  ```

### INT len\_req\_body()

- **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();
  ```

### VOID log\_req\_body(STRING prefix="", INT length=200)

- **Description**

  Log the request body to the VSL, making it available for other components. When logging, it takes an optional prefix and a max line length, so the body could be split up across multiple lines as there is a limit to how large a single line can be.

- **Example**

  ```
  | std.cache_req_body(1KB);
  | bodyaccess.log_req_body("PREFIX:", 3);
  ```