Editing Simplified HTTPS Configuration (section)

== Issues and Troubleshooting ==
Inevitably you may still encounter issues even if you use one of the configurations above, so it is advised you test this on a development or pre-production instance of your repository to check you get the behaviour you expect.

=== Search Engine Indexing ===
It has been observed in the past that some items may briefly disappear from the Google search index when switching to [[Simplified_HTTPS_Configuration#HTTPS_Only | HTTPS Only]].  There is no way to guarantee this will not happen.  One way to try to mitigate and keep on top of this is to setup a Google Webmaster account and register your repository's hostname.  After a couple of days this should get populated with all the pages indexed for your repositories, if there are any missing you can submit these to Google to be re-added.

=== IRStats2 Blip in Downloads ===
It has also been observed that repositories see a brief drop in downloads (and views) when switching to [[Simplified_HTTPS_Configuration#HTTPS_Only | HTTPS Only]].  This may be partially due to search engine indexing but is most likely affected by the fact that bots and crawlers (including GoogleBot) will not follow redirects (i.e. from the HTTP URL they already had to the new HTTPS version) and therefore this will not count as a download.  [https://eprints.github.io/irstats2/ IRStats2] has multifarious ways of detecting bots but it is likely a large percentage of downloads will still be due to bots.  Therefore, in some ways the blip may actually give a more accurate picture of the amount of downloads from your repository.  However, looking a raw statistic is generally a bad idea, [https://eprints.github.io/irstats2/ IRStats2] is intended to show usage trends and differences more than absolute downloads or views.

=== Bazaar Plugins ===
Effort has been taken to resolve any issues as a result of <tt>$c->{host}</tt> no longer being defined if you want to use HTTPS everywhere (with HTTPS redirects).  However, this can only be done to the extent of the core codebase.  Some [https://bazaar.eprints.org/ Bazaar] plugins may rely on <tt>$c->{host}</tt> being defined.  Below are the Bazaar plugins we are aware have issues.  This list is not exhaustive.

==== [http://bazaar.eprints.org/379/ Repository Links Plugin] ====
The Repository Links plugin uses the EPrints URL to lookup where it is used on other repositories.  If your repository is configured as one of the remote repositories, then the master repository will have been storing your repository URLs as HTTP up to the point you switch over to [[Simplified_HTTPS_Configuration#HTTPS_Only | HTTPS Only]].  When you do this it will start recording these URLs as HTTPS.

This creates two problems.  '''$c->{host}''' will not longer be set and this will prevent both the related links box for Repository Links being displayed on your repository's abstract pages but also the same box being displayed for the abstract pages for items on the master repository.  To fix this you will need to update '''$c->{host}''' to '''$c->{securehost}''' in '''/cgi/get_repo_links''' so the hostname will not be set in the request sent to the master repository.

Also. the protocol itself needs to be updated to '''https''' from '''http''' in the text that proceeds '''$c->{host}'''  in the same file.  This will ensure that it looks for https URLs which will now be stored on the master repository.  However, the master repository will still be storing http URLs for old items, so they will need to update all the URLs for your reposotory to https URLs to make the Repository Links related links box work on your repository, although the first change you fix the missing related links box on the master repository.

It is also probably worth updating the protocol used for making HTTP requests to the master repository to use https as well, assuming it is configured to support HTTPS.

It is unclear if and what changes would be necessary if your repository is the master repository for the Repository Links plugin.  However, as a minimum you should make the changes described above and check any other Repository Link plugin files for the use of '''$c->{host}''' to '''$c->{securehost}''' and ensure the https is used as the protocol wherever http is currently being used.

=== EPrint URI Change ===
When an EPrint made live it will acquire a URI in the form

 <nowiki>http://example.eprints.org/eprint/id/1234</nowiki>

If you switch over to [[Simplified_HTTPS_Configuration#HTTPS_Only | HTTPS Only]] the above URI will be updated (if you refresh abstracts) to

 <nowiki>https://example.eprints.org/eprint/id/1234</nowiki>

For most repositories this will not be an issue but if your repository is harvested by a third party application, it may rely on the URI as a unique identifier and if this changes it may that all the EPrints are new as none of the URIs are the same as before.

For third party applications that integrate through the [http://bazaar.eprints.org Bazaar] (EThoS, PIRUS, Symplectic Repository Tools, etc.) no problems relating to this have been identified.  However, if your repository has a bespoke third party application this may be affected and is something you should test beforehand if possible but as soon as you go live with the new configuration otherwise.

If you need to ensure your EPrint URIs do not change you can add the <code>uri_url</code> configuration option at the end of your archive's <code>10_core.pl</code> configuration as follows:

 $c->{uri_url} = "http://" . $c->{securehost};

OAI-PMH (e.g. <nowiki>http://example.eprints.org/cgi/oai2</nowiki> and <nowiki>https://example.eprints.org/cgi/oai2</nowiki>) provide different relations (http or https) for a publication but the OAI identifier is protocol independent and therefore stays the same.  Therefore, third party applications that make use of OAI-PMH should not be affected if they harvest as the protocol specifies.