1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
#-
# Copyright (c) 2010-2014 Varnish Software AS
# All rights reserved.
#
# Author: Poul-Henning Kamp <phk@FreeBSD.org>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
$Module std 3 Varnish Standard Module
DESCRIPTION
===========
Vmod_std contains basic functions which are part and parcel of Varnish,
but which for reasons of architecture fit better in a VMOD.
One particular class of functions in vmod_std is the conversions functions
which all have the form::
TYPE type(STRING, TYPE)
These functions attempt to convert STRING to the TYPE, and if that fails,
they return the second argument, which must have the given TYPE.
$Function STRING toupper(STRING_LIST)
Description
Converts the string *s* to upper case.
Example
set beresp.http.x-scream = std.toupper("yes!");
$Function STRING tolower(STRING_LIST)
Description
Converts the string *s* to lower case.
Example
set beresp.http.x-nice = std.tolower("VerY");
$Function VOID set_ip_tos(INT)
Description
Sets the Type-of-Service flag for the current session. Please
note that the TOS flag is not removed by the end of the
request so probably want to set it on every request should you
utilize it.
Example
| if (req.url ~ ^/slow/) {
| std.set_ip_tos(0x0);
| }
$Function REAL random(REAL, REAL)
Description
Returns a random REAL number between *a* and *b*.
Example
set beresp.http.x-random-number = std.random(1, 100);
$Function VOID log(STRING_LIST)
Description
Logs *string* to the shared memory log, using VSL tag *SLT_VCL_Log*.
Example
std.log("Something fishy is going on with the vhost " + req.host);
$Function VOID syslog(INT, STRING_LIST)
Description
Logs *string* to syslog marked with *priority*. See your
system's syslog.h file for the legal values of *priority*.
Example
std.syslog(8 + 1, "Something is wrong");
$Function STRING fileread(PRIV_CALL, STRING)
Description
Reads a file and returns a string with the content. Please
note that it is not recommended to send variables to this
function the caching in the function doesn't take this into
account. Also, files are not re-read.
Example
set beresp.http.x-served-by = std.fileread("/etc/hostname");
$Function VOID collect(HEADER)
Description
Collapses the header, joining the headers into one.
Example
std.collect(req.http.cookie);
This will collapse several Cookie: headers into one, long
cookie header.
$Function DURATION duration(STRING, DURATION)
Description
Converts the string *s* to seconds. *s* must be quantified
with ms (milliseconds), s (seconds), m (minutes), h (hours),
d (days), w (weeks) or y (years) units. If *s* fails to parse,
*fallback* will be returned.
Example
set beresp.ttl = std.duration("1w", 3600s);
$Function INT integer(STRING, INT)
Description
Converts the string *s* to an integer. If *s* fails to parse,
*fallback* will be returned.
Example
if (std.integer(beresp.http.x-foo, 0) > 5) { ... }
$Function IP ip(STRING, IP)
Description
Converts string *s* to the first IP number returned by
the system library function getaddrinfo(3). If conversion
fails, *fallback* will be returned.
Example
if (std.ip(req.http.X-forwarded-for, "0.0.0.0") ~ my_acl) { ... }
$Function REAL real(STRING, REAL)
Description
Converts the string *s* to a real. If *s* fails to parse,
*fallback* will be returned.
Example
set req.http.x-real = std.real(req.http.x-foo, 0.0);
$Function TIME real2time(REAL)
Description
Converts the real *r* to a time.
Example
set req.http.x-time = std.real2time(1140618699.00);
$Function INT time2integer(TIME)
Description
Converts the time *t* to a integer.
Example
set req.http.x-int = std.time2integer(now);
$Function REAL time2real(TIME)
Description
Converts the time *t* to a real.
Example
set req.http.x-real = std.time2real(now);
$Function BOOL healthy(BACKEND)
Description
Returns true if the backend is healthy.
$Function INT port(IP)
Description
Returns the port number of an IP address.
$Function VOID rollback(HTTP)
Description
Restore *h* HTTP headers to their original state.
Example
std.rollback(bereq);
$Function VOID timestamp(STRING)
Description
Introduces a timestamp in the log with the current time. Uses
the argument as the timespamp label. This is useful to time
the execution of lengthy VCL procedures, and makes the
timestamps inserted automatically by Varnish more accurate.
Example
std.timestamp("curl-request");
$Function STRING querysort(STRING)
Description
Sorts the querystring for cache normalization purposes.
Example
set req.url = std.querysort(req.url);
$Function STRING strstr(STRING, STRING)
Description
Returns the substring if the second string is a substring of the first
string. Note that the comparison is case sensitive. You can
use the tolower function on both strings if you want case
insensitivity.
If there is no match a NULL pointer is returned which would
evaluate to false in an if-test.
Example
if (std.strstr(req.url, req.http.x-restrict))
SEE ALSO
========
* vcl(7)
* varnishd(1)
HISTORY
=======
The Varnish standard module was released along with Varnish Cache 3.0.
This manual page was written by Per Buer with help from Martin Blix
Grydeland.
COPYRIGHT
=========
This document is licensed under the same licence as Varnish
itself. See LICENCE for details.
|
