Future of the shadow list

[FriedrichFroebel]

The shadow list feature with not publicly shown duplicates on GC and OC has recently been disabled due to problems with the API endpoint provided by Opencaching.de, namely https://www.opencaching.de/api/gc2oc.php. The endpoint is currently returning empty files instead of valid GZip archives with the requested data.

It seems like the corresponding endpoint has been removed from the Opencaching.de code (development version) on 2020-01-12 (commit 1720ea5), so I assume that we will not be able to use this endpoint in the future anymore. According to a commit from 2016-01-18 (commit 89d813c) this endpoint had been introduced especially for cmanager, but as the original version does not further support Opencaching.de, some issues/functionalities have been discontinued there.

In fact there is an older API being an alternative to the OKAPI (in reality it probably is the predecessor) returning XML which should contain the manually set shadow entries as well. When performing a query for all caches and looking at the gccom and gccom2 attributes for the waypoints, they seemed to be identical for each entry. In fact sometimes the shadow entry gccom2 should have been different (when the gccom attribute is empty, which means that this GC code has not officially been set by the owner), but both attributes match in all cases. According to the commits, the XML API has been removed from the code (development version) on 2020-01-12 (commit e02ca45) as well.

We will have to monitor this and are probably safe to remove the corresponding code later on.

[FriedrichFroebel]

As already mentioned inside the comments on #21, I started maintaining an own mapping table with the data provided by the OKAPI. We should use a separate class for this translation table where one GC code can have multiple OC codes and replace the current references to the ShadowList class with this version (this is not a shadow list any more, but the official mapping as specified by the owners).

At the moment the actual data is not available to the public - if anyone wants to start working on this, feel free to drop me a message. As soon as this is implemented, the data will be published of course.

[FriedrichFroebel]

With the latest push to the live server the APIs removed in the development version mentioned above are not available anymore and respond with an error code 404.

[FriedrichFroebel]

Now once we rely on the OKAPI search functionality to skip own geocaches, we have to implement this manually for the shadow list revamp.