webperl/mdfiles/config.md

Configuration

The webperl framework includes a basic configuration file reader and writer in the form of the ConfigMicro class. The ConfigMicro class provides methods for loading simple '.ini style' configuration files, supporting sections and key-value pairs, eg:

[sectionA]
keyA = valueA
keyB = valueB

[sectionB]
keyC = valueC

When using the Application class as the basis of a web application, you need to provide a configuration file (the name of which defaults to 'config/site.cfg', but you can change this via the config argument to Application::new()) containing, minimally, the following:

[database]
database = DBI:mysql:DATABASE
username = USERNAME
password = PASSWORD

# Standard webperl tables
auth_methods   = rev_auth_methods
auth_params    = rev_auth_methods_params
blocks         = rev_blocks
keys           = rev_session_keys
modules        = rev_modules
sessions       = rev_sessions
settings       = rev_settings

the database section must be present in the configuration at some point - you may include other sections if you wish, but database must be present. The database section must include the keys database, username, and password providing the credentials that should be used to connect to the webapp's database. Most of the webperl code has only been tested with MySQL, other databases may or may not work well with it.

The database section should also contain the mapping from internal table names to actual table names, often this will be a matter of sticking on a prefix, as shown above, or possibly even straight duplication. Unfortunately there is no support currently for automatic generation of these aliases, so each table you use should have an entry in the database section.

Once the configuration has been loaded, and the connection to the database established, the contents of the settings table are loaded into the config section of the configuration object.

Blocks invoked via Application are passed the configuration in the "settings" reference, and can access the sections of the configuration using code like

$self -> {"settings"} -> {"database"} -> {"auth_methods"}
$self -> {"settings"} -> {"config"} -> {"base"}

If your code updates values in the config section values, you should use ConfigMicro::save_db_config() or ConfigMicro::set_db_config() to make your changes persistent.

As noted above, the configuration file may contain more sections than just the database section, so it is perfectly valid to do things like

[database]
... as above...

[foo]
bar  = wibble
quux = fred

And your blocks may access the additional section via, for example,

$self -> {"settings"} -> {"foo"} -> {"bar"}