HttpSplitClientsModule - Revision history

Willybarro: /* Examples */

2013-01-02T18:01:49Z

‎Examples

Willybarro: /* Basic configuration: */

2013-01-02T17:43:02Z

‎Basic configuration:

Willybarro: /* Sending a query string variable to 51% of clients (to PHP scripts) */

2013-01-02T17:42:11Z

‎Sending a query string variable to 51% of clients (to PHP scripts)

Willybarro: Explaining how the murmurhash2 integer is used to determine which variable value shall be set.

2012-12-11T14:03:42Z

Explaining how the murmurhash2 integer is used to determine which variable value shall be set.

Willybarro: Murmurhash to Murmurhash2

2012-11-23T17:54:29Z

Murmurhash to Murmurhash2

Willybarro: Add quotes to improve readability. Remove "-" directive as it's not accepted anymore. Overview about how the percentage calculation works. Example of how to add a query string based on split clients.

2012-11-23T17:50:58Z

Add quotes to improve readability. Remove "-" directive as it's not accepted anymore. Overview about how the percentage calculation works. Example of how to add a query string based on split clients.

Admin: /* split_clients */

2012-05-02T19:38:36Z

‎split_clients

Admin: /* split_clients */

2012-04-30T17:45:46Z

‎split_clients

VBart: /* References */ Added link to the original documentation

2012-04-21T15:39:53Z

‎References: Added link to the original documentation

Ensiferous: Fixed underscore instead of dash in directive names.

2011-08-20T00:09:17Z

Fixed underscore instead of dash in directive names.

New page

= Synopsis =

ngx_http_split_clients_module is used to split clients based on some conditions(e.g ip addresses, headers, cookies, etc).

Example configuration:
<geshi lang="nginx">
http {
split_clients "${remote_addr}AAA" $variant {
0.5% .one;
2.0% .two;
- "";
}

server {
location / {
index index${variant}.html;
</geshi>

$cookie_..., etc, may be used as a source for splitting. The source string is hashed using MurmurHash2 (as of 1.0.1; previously CRC32) and the percent of the hash is used as source value.

= Directives =

== split_clients ==
'''syntax:''' ''split_clients $variable { ... } ''

'''default:''' ''none''

'''context:''' ''http''

= References =

* [http://www.ruby-forum.com/topic/209653 Naming convention discussion]

@@ Line 24: / Line 24: @@
 * Hash values from 0 to 1739461754 (40.5%) will set the $variant variable with the value ".one" and will try to load the file "index.one.html";
 * Hash values from 1739461755 to 4294967295 (59.5%) will set the $variant variable with the value ".two" and will try to load the file "index.two.html";
 == Sending a query string variable to 51% of clients (to PHP scripts) ==
@@ Line 47: / Line 40: @@
+     }
 </geshi>
 = Directives =

@@ Line 22: / Line 22: @@
 On the sample configuration above, the input for calculating the percentage is the variable plus string ('''"${remote_addr}AAA"'''). The value of this string is hashed using MurmurHash2 (which will generate a 32bit integer).
 In the example given:
-* Hash values from 0 to 1739461754 (40.5%) will set the $variant variable with the value ".one";
+* Hash values from 0 to 1739461754 (40.5%) will set the $variant variable with the value ".one" and will try to load the file "index.one.html";
-* Hash values from 1739461755 to 4294967295 (59.5%) will set the $variant variable with the value ".two";
+* Hash values from 1739461755 to 4294967295 (59.5%) will set the $variant variable with the value ".two" and will try to load the file "index.two.html";
 == Appendix ==

@@ Line 42: / Line 42: @@
      server {
          location ~ \.php$ {
-             set $args "${query_string}&${$additionalQsVariable}";
+             set $args "${query_string}&${additionalQsVariable}";
              [...]
+         }

@@ Line 20: / Line 20: @@
 </geshi>
-On the example configuration above, the input for calculating the percentage is the variable plus string ('''"${remote_addr}AAA"'''). This string will be converted into a percentage value using ''MurmurHash2'', the result will be compared to the directives and fill the $variant variable with the value just after the percentage in the configuration directives.
+On the sample configuration above, the input for calculating the percentage is the variable plus string ('''"${remote_addr}AAA"'''). The value of this string is hashed using MurmurHash2 (which will generate a 32bit integer).
-Instead of '''${remote_addr}''', one could use '''${cookie}''', '''${args}''' or another [http://wiki.nginx.org/HttpCoreModule#Variables, nginx variable]. You may also add a salt (arbitrary string) if needed.
+== Appendix ==
 * Keep in mind that if you use a variable like '''${remote_addr}''' (user IP), the hash (and percentage) will always be the same as long as the user/client keep the same IP. In other words, the '''$variant''' value will always be the same for the same IP.

@@ Line 25: / Line 25: @@
 * Keep in mind that if you use a variable like '''${remote_addr}''' (user IP), the hash (and percentage) will always be the same as long as the user/client keep the same IP. In other words, the '''$variant''' value will always be the same for the same IP.
-* Hashing algorithm is MurmurHash since version 1.0.1; Previously CRC32.
+* Hashing algorithm is MurmurHash2 since version 1.0.1; Previously CRC32.
 == Sending a query string variable to 51% of clients (to PHP scripts) ==

@@ Line 3: / Line 3: @@
 ngx_http_split_clients_module is used to split clients based on some conditions(e.g ip addresses, headers, cookies, etc).
-Example configuration:
+= Examples =
 <geshi lang="nginx">
 http {
      split_clients "${remote_addr}AAA" $variant {
-.5% .one;
+.5% ".one";
-.0% .two;
+.5% ".two";
-        - "";
+     }
@@ Line 15: / Line 16: @@
          location / {
               index index${variant}.html;
 </geshi>
-$cookie_..., etc, may be used as a source for splitting. The source string is hashed using MurmurHash2 (as of 1.0.1; previously CRC32) and the percent of the hash is used as source value.
+On the example configuration above, the input for calculating the percentage is the variable plus string ('''"${remote_addr}AAA"'''). This string will be converted into a percentage value using ''MurmurHash2'', the result will be compared to the directives and fill the $variant variable with the value just after the percentage in the configuration directives.
 = Directives =

@@ Line 22: / Line 22: @@
 == split_clients ==
-<include wikitext nopre src="http://wiki.nginx.org/nginx.org/ngx_http_split_clients_module/split_clients.txt" />
+<include wikitext nopre src="http://wiki.nginx.org/nginx.org/http/ngx_http_split_clients_module/split_clients.txt" />
 = References =

← Older revision		Revision as of 15:39, 21 April 2012
Line 30:		Line 30:
	= References =		= References =

		+	* [http://nginx.org/en/docs/http/ngx_http_split_clients_module.html Original Documentation]
	* [http://www.ruby-forum.com/topic/209653 Naming convention discussion]		* [http://www.ruby-forum.com/topic/209653 Naming convention discussion]