================================================================
=== PKP Preservation Network Plugin for OJS
=== Version: (see version.xml)
=== Author: Chris MacDonald <[email protected]>
=== Author: Michael Joyce <[email protected]>
=== Author: Dimitris Efstathiou <[email protected]>
================================================================

About
-----
This plugin provides a means for OJS to preserve content in the PKP
Preservation Network (PKP|PN). The plugin checks for new and modified content
and provided the PN's terms of use are met, will communicate with the PN's
staging server to preserve your published content automatically.

License
-------
This plugin is licensed under the GNU General Public License v3. See the
file LICENSE for the complete terms of this license.

System Requirements
-------------------
- OJS 3.2.1-x.
- CURL support for PHP.
- ZipArchive support for PHP.

Note
----
The primary difference between this plugin and the existing LOCKSS preservation
mechanism present in OJS is the PN requires no registration or involvement with
the network - as long as you agree with the network's terms of use, you can
preserve your journal's content.

Contact/Support
---------------
Please use the PKP support forum (http://forum.pkp.sfu.ca/), PKP issue
tracker (https://github.com/pkp/pkp-lib/issues) or email the authors for
support, bugfixes, or comments.

Setting a default
-----------------
By default, the PLN plugin deposits to http://pkp-pln.lib.sfu.ca. Journal
managers can change the URL on the plugin settings page. The default URL can
also be set in the OJS config.inc.php file by adding this configuration:

; Change the default PLN
[lockss]
pln_url = http://example.com

You will need to clear the data caches after adding or changing this setting.
There is a link to clear the caches at
Site Administration > Administrative Functions

Version History
---------------
-1.0	- Initial Release
-1.0.1	- Make upgraded plugins use default settings
-1.0.2	- Bug fixes, add terms of use acceptance to the gateway, add setting for
          default network URL. 
-2.0.x	- Porting PLN Plugin to OJS 3.x

Installation Instructions
-------------------------
We recommend installing this plugin using the Plugin Gallery within OJS. Log in
with administrator privileges, navigate to Settings > Journal > Plugins, and
choose the Plugin Gallery. Find the PLN plugin there and follow the
instructions to install it.

Build Instructions
------------------
(These instructions are only necessary if you are working with the plugin
manually. If you are installing the plugin using the Plugin Gallery, they are
not necessary.)

The plugin depends on the BagIt component
(https://packagist.org/packages/scholarslab/bagit) and it incorporates it as a
Composer (https://getcomposer.org/) module. Please make sure you have Composer
installed before installing the plugin.

- Clone the repository containing the code.
- Run OJS's "php tools/upgrade.php upgrade"
- Execute "composer install" from console, being in the cloned pln folder.
  (This process is going to produce a "vendor" folder containing the depending
  library.)
- Enable Acron plugin and change config.inc.php variable scheduled_tasks = On
- Enable the pln plugin

Other useful hints / Troubleshooting hints
------------------------------------------------
- The pln plugin depends on 2 database tables, namely the 'pln_deposits' and
  'pln_deposit_objects' tables. If those tables are not in your database, you
  may not have installed the plugin properly.

- The 'plugins.generic.pln.classes.tasks.Depositor' task must be inside the
  'scheduled_tasks' database table. If not, try 'Reload Scheduled Tasks' from
  the Plugins gallery area, under the Acron plugin.

- Search the plugin's logs in the 'scheduledTaskLogs' folder within the OJS
  files directory. Files named 'PKPPLNDepositorTask-*id*-*datestamp*' should
  be found there.

- In the scheduled task log files, if an entry like '[*date time*] [Notice] Task
  process stopped.' is found, then the process seems to have exited as it
  should. Otherwise please check the PHP logs for more info/errors.

- If an issue fails to be packaged, it may be useful to try and export the issue
  from the native import/export plugin. Possible export problems may cause the
  PLN Plugin to fail to send the failed content, and the native import/export
  plugin may display some hints on why the failure occured.