1.1. Overview

Domain module implements checks that based on domain table determine if a host part of an URI is "local" or not. A "local" domain is one that the proxy is responsible for.

Domain module operates in caching or non-caching mode depending on value of module parameter db_mode. In caching mode domain module reads the contents of domain table into cache memory when the module is loaded. After that domain table is re-read only when module is given domain_reload fifo command. Any changes in domain table must thus be followed by domain_reload command in order to reflect them in module behavior. In non-caching mode domain module always queries domain table in the database.

Caching is implemented using a hash table. The size of the hash table is given by HASH_SIZE constant defined in domain_mod.h. Its "factory default" value is 128.

1.2. Dependencies

The module depends on the following modules (in the other words the listed modules must be loaded before this module):

• database -- Any database module

1.3. Exported Parameters

modparam("domain", "db_url", "mysql://ser:pass@db_host/ser")

modparam("domain", "db_mode", 1)   # Use caching

modparam("domain", "domain_table", "new_name")

modparam("domain", "domain_column", "domain_col")

1.4. Exported Functions

...
if (is_from_local()) {
	...
};
...
		

...
if (is_uri_host_local()) {
	...
};
...
		

1.5. FIFO Commands

1.6. Known Limitations

There is an unlikely race condition on domain list update. If a process uses a table, which is reloaded at the same time twice through FIFO, the second reload will delete the original table still in use by the process.