Elektra
0.8.17
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Following the elektra keyname convention application configurations are stored under /sw/org/myapp/#
and /sw/org/myapp/#0/current
is the profile to be used. The profile
plugin provides an easy way to switch configuration profiles.
The key /sw/org/myapp/#0/profile
defines what profile should be used as current
, e.g. /sw/org/myapp/#0/profile = myprofile
. If a key /sw/org/myapp/#0/myprofile/key
is found and no key /sw/org/myapp/#0/current/key
exists an override key will be created linking /sw/org/myapp/#0/currrent/key
to /sw/org/myapp/#0/myapp/key
If neither /sw/org/myapp/#0/current/key
nor /sw/org/myapp/#0/myprofile/key
is found, but /sw/org/myapp/#0/%/key
, /sw/org/myapp/#0/current/key
will be linked to /sw/org/myapp/#0/%/key
.
So a cascading lookup will automatically implement following preferences (next to the namespace preferences):
current
profile
%
fallback profileSuppose we have the configuration file profile.ini in ~/.config:
% cat profile.ini ``` [] profile = myprofile
[current] key2 = will win
[myprofile] key1 = test1 key2 = test2
[%] key2 = failed? key3 = test3 ```
Then we simply mount it without the profile plugin:
% kdb mount profile.ini /sw/org/myapp/#0 ini
But we have to make sure that the profile plugin is mounted globally:
% kdb global-mount profile
Then we can access /sw/org/myapp/#0 in a profile-aware way:
% kdb ls /sw ``` spec/sw/org/myapp/#0/current/key1 spec/sw/org/myapp/#0/current/key3 user/sw/org/myapp/#0 user/sw/org/myapp/#0/% user/sw/org/myapp/#0/%/key2 user/sw/org/myapp/#0/%/key3 user/sw/org/myapp/#0/current user/sw/org/myapp/#0/current/key2 user/sw/org/myapp/#0/profile user/sw/org/myapp/#0/myprofile user/sw/org/myapp/#0/myprofile/key1 user/sw/org/myapp/#0/myprofile/key2 ```
As we can see with the -v
option, we will fetch keys from our myprofile
even though we request current
:
% kdb get -v /sw/org/myapp/#0/current/key1 ``` got 25 keys searching spec/sw/org/myapp/#0/current/key1, found: spec/sw/org/myapp/#0/current/key1, options: KDB_O_CALLBACK The resulting keyname is user/sw/org/myapp/#0/myprofile/key1 test1 ```
To switch profile we simply have to set one key: ``` kdb set user/sw/org/myapp/#0/profile newprofile ```
Usually, this will be done via commandline by setting proc/sw/org/myapp/#0/profile
.