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In summary, use the plugin command that ships with the IdP to install the plugin from either a local file pre-downloaded, or from a URL or by pluginId 4.2
Installation
C:>\opt\shibboleth-idp\bin\plugin.bat -I net.shibboleth.idp.plugin.oidc.whatever
or
$ /opt/shibboleth-idp/bin/plugin.sh -i <plugin.tar.gz>
or
C:>\opt\shibboleth-idp\bin\plugin.bat -i <plugin.zip>http://shibboleth.net/downloads/identity-provider/plugins/pluginName/version/URL
or
$ /opt/shibboleth-idp/bin/plugin.sh -i <plugin.tar.gz>
If installing from a local file, you need to ensure the GPG detached signature (e.g. the .asc file) is placed alongside the main plugin archive on disk.
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