Plugin: multifile

• infos = Information about the multifile plugin is in keys below
• infos/author = Thomas thoma.nosp@m.s.wa.nosp@m.ser@l.nosp@m.ibel.nosp@m.ektra.nosp@m..org
• infos/licence = BSD
• infos/needs =
• infos/provides = resolver storage
• infos/recommends =
• infos/placements = getresolver setresolver commit rollback getstorage setstorage
• infos/status = compatible specific shelltest nodep configurable
• infos/metadata =
• infos/description = mounts multiple files within a directory

Introduction

For some applications it is beneficially to have multiple configuration files. One way to achieve this, is to mount different files for the application.

In some situations we are not able to specify every configuration file with separate mounts because new configuration files might be created any time. Instead we want to include every configuration file matching a given pattern.

The multifile-resolver does so by calling resolver and storage plugins for each file matching a given pattern.

Plugin Configuration

• recursive: If present, fts (3) will be used to traverse the directory tree and fnmatch to match pattern to the filename. If not present, glob (3) with pattern will be used on the directory
• pattern: The pattern to be used to match configuration files.
• storage: The storage plugin to use.
• resolver: The resolver plugin to use.
• 'child/<configname>': configuration passed to the child backends, child/ part gets removed.

Usage

kdb mount -R multifile -c storage="toml",pattern="*/*.toml",resolver="resolver" /path /mountpoint

kdb mount -R multifile -c storage="toml",pattern="*.toml",recursive=,resolver="resolver" /path /mountpoint

Examples

rm -rf $(dirname $(kdb file user:/))/multitest || $(exit 0)
mkdir -p $(dirname $(kdb file user:/))/multitest || $(exit 0)
 
cat > $(dirname $(kdb file user:/))/multitest/lo.toml << EOF \
[lo]\
addr = "127.0.0.1"\
encap = "Loopback"\
EOF
 
cat > $(dirname $(kdb file user:/))/multitest/lan.toml << EOF \
[eth0]\
addr = "192.168.1.216"\
encap = "Ethernet"\
EOF
 
cat > $(dirname $(kdb file user:/))/multitest/wlan.toml << EOF \
[wlan0]\
addr = "192.168.1.125"\
encap = "Ethernet"\
EOF
 
sudo kdb mount -R multifile -c storage="toml",pattern="*.toml",resolver="resolver" multitest user:/tests/multifile
 
kdb ls user:/tests/multifile
#> user:/tests/multifile/lan.toml/eth0
#> user:/tests/multifile/lan.toml/eth0/addr
#> user:/tests/multifile/lan.toml/eth0/encap
#> user:/tests/multifile/lo.toml/lo
#> user:/tests/multifile/lo.toml/lo/addr
#> user:/tests/multifile/lo.toml/lo/encap
#> user:/tests/multifile/wlan.toml/wlan0
#> user:/tests/multifile/wlan.toml/wlan0/addr
#> user:/tests/multifile/wlan.toml/wlan0/encap
 
kdb set user:/tests/multifile/lan.toml/eth0/addr 10.0.0.2
 
kdb get user:/tests/multifile/lan.toml/eth0/addr
#> 10.0.0.2
 
kdb get user:/tests/multifile/lan.toml/eth0/encap
#> Ethernet
 
cat > $(dirname $(kdb file user:/))/multitest/test.toml << EOF \
[testsection]\
key = "val"\
EOF
 
kdb ls user:/tests/multifile/test.toml
#> user:/tests/multifile/test.toml/testsection
#> user:/tests/multifile/test.toml/testsection/key
 
kdb ls user:/tests/multifile
#> user:/tests/multifile/lan.toml/eth0
#> user:/tests/multifile/lan.toml/eth0/addr
#> user:/tests/multifile/lan.toml/eth0/encap
#> user:/tests/multifile/lo.toml/lo
#> user:/tests/multifile/lo.toml/lo/addr
#> user:/tests/multifile/lo.toml/lo/encap
#> user:/tests/multifile/test.toml/testsection
#> user:/tests/multifile/test.toml/testsection/key
#> user:/tests/multifile/wlan.toml/wlan0
#> user:/tests/multifile/wlan.toml/wlan0/addr
#> user:/tests/multifile/wlan.toml/wlan0/encap
 
kdb rm -r user:/tests/multifile/test.toml
 
stat $(dirname $(kdb file user:/))/multifile/test.toml
# RET:1
 
sudo kdb umount user:/tests/multifile
rm -rf $(dirname $(kdb file user:/))/multitest || $(exit 0)

Limitations

• You cannot get rid of the configuration file name.
• You cannot create or delete configuration files.
• The resolving will always be done with the default resolver plugin, despite the configuration option.
• Not all file names are supported (see https://issues.libelektra.org/2124)
• Cannot handle conflicts (see https://issues.libelektra.org/2527)