dns_cache Module

This module is an implementation of a cache system designed for DNS records. For successful DNS queries of all types, the module will store in a cache/db backend the mappings, for TTL number of seconds received in the DNS answer. Failed DNS queries will also be stored in the back-end, with a TTL that can be specified by the user. The module uses the Key-Value interface exported from the core.

1.2. Dependencies

1.2.1. OpenSIPS Modules

A cachedb_* type module must be loaded before loading the dns_cache module.

1.3. Exported Parameters

1.3.1. `cachedb_url` (string)

The url of the key-value back-end that will be used for storing the DNS records.

Example 1.1. Set cachedb_url parameter

...
#use internal cachedb_local module
modparam("dns_cache", "cachedb_url","local://")
#use cachedb_memcached module with memcached server at 192.168.2.130
modparam("dns_cache", "cachedb_url","memcached://192.168.2.130:8888/")
...

1.3.2. `blacklist_timeout` (int)

The number of seconds that a failed DNS query will be kept in cache. Default is 3600.

Example 1.2. Set blacklist_timeout parameter

...
modparam("dns_cache", "blacklist_timeout",7200) # 2 hours
...

1.4. Exported Functions

The module does not export functions to be used in configuration script.

Chapter 2. Contributors

2.1. By Commit Statistics

Table 2.1. Top contributors by DevScore⁽¹⁾, authored commits⁽²⁾ and lines added/removed⁽³⁾

	Name	DevScore	Commits	Lines ++	Lines --
1.	Vlad Paiu (@vladpaiu)	15	5	1006	3
2.	Liviu Chircu (@liviuchircu)	13	11	50	48
3.	Razvan Crainea (@razvancrainea)	11	9	12	14
4.	Bogdan-Andrei Iancu (@bogdan-iancu)	8	6	16	7
5.	Maksym Sobolyev (@sobomax)	3	1	2	2
6.	Peter Lemenkov (@lemenkov)	3	1	1	1
7.	Vlad Patrascu (@rvlad-patrascu)	2	1	1	0

(1) DevScore = author_commits + author_lines_added / (project_lines_added / project_commits) + author_lines_deleted / (project_lines_deleted / project_commits)

(2) including any documentation-related commits, excluding merge commits. Regarding imported patches/code, we do our best to count the work on behalf of the proper owner, as per the "fix_authors" and "mod_renames" arrays in opensips/doc/build-contrib.sh. If you identify any patches/commits which do not get properly attributed to you, please submit a pull request which extends "fix_authors" and/or "mod_renames".

(3) ignoring whitespace edits, renamed files and auto-generated files

2.2. By Commit Activity

Table 2.2. Most recently active contributors⁽¹⁾ to this module

	Name	Commit Activity
1.	Maksym Sobolyev (@sobomax)	Feb 2023 - Feb 2023
2.	Liviu Chircu (@liviuchircu)	Mar 2014 - Apr 2021
3.	Bogdan-Andrei Iancu (@bogdan-iancu)	Jun 2012 - Mar 2020
4.	Razvan Crainea (@razvancrainea)	Feb 2012 - Sep 2019
5.	Peter Lemenkov (@lemenkov)	Jun 2018 - Jun 2018
6.	Vlad Patrascu (@rvlad-patrascu)	May 2017 - May 2017
7.	Vlad Paiu (@vladpaiu)	Feb 2012 - Oct 2012

(1) including any documentation-related commits, excluding merge commits

Chapter 3. Documentation

3.1. Contributors

Last edited by: Razvan Crainea (@razvancrainea), Peter Lemenkov (@lemenkov), Liviu Chircu (@liviuchircu), Bogdan-Andrei Iancu (@bogdan-iancu), Vlad Paiu (@vladpaiu).