Tigerfell's diary

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Documenting the history of OpenStreetMap

Posted by Tigerfell on 30 January 2019 in English (English)

Did you ever come across wiki pages like Proposed Features/UUID or Yahoo! Aerial Imagery and wondered what to do with the information as the pages are not “current” any more?

As one could have guessed, there are basically two approaches on these cases. One approach is to store current information only and consequently delete information as soon as it becomes historic. The other approach aims at documenting the full history of all tagging and all applications ever used.

The strongest reason for the first approach is the argument that historic information might be confusing for the readers and might lead to “wrong” tagging or poor decidions regarding software deployment. Referring to my first example, one can see that the page features two red boxes. Both state that the proposed feature is abandoned. There are links to Query-to-map and Humanitarian OSM tags (marked as outdated itself), but a link to the general concept page Permanent ID featuring the background as well as an overview of the approaches is missing. On the other hand, this page serves as a documentation for the keys uuid:place and similar. This information might be lost if someone would delete the page or radically change its content (in the latter case you could still retrieve the content from the page’s history in case you know the page name).

Trash bin icon Trash or recycle? (Image CC0)

Secondly, some users argue that outdated pages (esp. proposals) lack unique and thought-through ideas and therefore the reason to be “worth” archiving. The analogy is an outdated technical guide describing steps for installation which can not be done any more because the systems necessary to run the installation are unavailable today as technology has advanced significantly and new APIs have emerged whilst other services have creased to exist. The other side argues that understanding the history helps understanding current OpenStreetMap. An illustrative example is provided by Yahoo! Aerial Imagery. Providing the means of armchair mapping, Yahoo’s imagery paved the way for a new mapping technique at its time. The step from Yahoo-provided imagery to current Bing’s services seems small compared to tracking GPS outside only and tracing aerial imagery at home.

Facing the challenge that outdated pages are marked differently and sometimes not at all, wiki users have come up with templates like Template:Archived proposal or (more recently) Template:Historic artifact start. The templates do not solve the dispute itself but hopefully avoid misunderstandings regarding currentness.

The decision what to include in the documentation of OpenStreetMap’s history has not been made yet. There are still reverts of edits in this case. A number of pages about former render software “Kosmos” is marked for deletion. I hope we will eventually find a solution together.

The following questions need to be assessed in my opinion:

  • Which pages should be kept in the wiki for documentation purposes?
  • Should they be changed to reflect their historical relevance? (How?)

I would like to discuss this in the forum: Please feel free to join.

Wiki: new "relation" template available, "area", "way", and "node" to come

Posted by Tigerfell on 30 September 2018 in English (English)

The rewrite of template relation is done. Almost all pages are changed. The template is currently the 47th most transcluded page with more than 5200 wiki pages using it.

Reflections on the work done

  • Writing on the template page to call the module (new Lua code for the template) was more of a struggle than I thought.
  • Parsing of longer pages is possible now (even though that was simplified as the parsing limits were increased while I was working on the template) (reference page
  • While working I figured out that this template has more functionalities. So, I eventually also included translations. That was not planned at the beginning.
  • Few users spoke up when I asked them for reviews. However, this was still helpful.
  • With all waiting for speak-up and coding, it took me 27 days to perform this change (on some days I did not work on it of course). I will speed up in future actions.

Work to do

  • Changing templates “area”, “way”, and “node”. You are again invited to suggest things and review my work. The basic goal is to align them to “relation” by using a common appearance and to increase usability on long pages.
  • Change the dropped features to a fixed wiki text: There used to be the option to use the template, without passing an ID to the template. This used to result in the template showing the text: “relation not defined yet”. The new template does not offer this ability. In order keep the old pages, I would like to edit the relevant wiki pages in a semi-automated process. I will request this separately (automated edits code of conduct) ideally after changing the other templates as well (for which I also plan to drop this functionality).

If you want to get a first glimpse of my plans, please refer to current documentation of the relation template. I am basically planning to do the same things on the other templates as well.

Rewriting a commonly used template for the wiki

Posted by Tigerfell on 4 September 2018 in English (English)

I am currently planning to rewrite the Relation template for the OpenStreetMap-Wiki. You can find the current version along with its documentation in the wiki. In the following text I would like to outline the objections behind my proposed rewrite and invite you to participate.

Purpose of the template

  • common appearance and functionality (general goal of templates)
  • maintainability as the wiki markup is just saved once, so if a tool is obsoleted, it can be removed from the template
  • referring to relations in wiki articles
  • creating links to tools automatically
  • often used to document the mapping status of relations in wikitables

Reasons for a rewrite

  • This template is commonly used and causes many pages to exceed their page limits. You can see the effects of this on the bottom of the wiki page about Beijing buses.
  • Some of the tools featured in the template are not accessible anymore.
  • The default settings cause all tool links to appear, but this is often not desired by the editors.
  • The template’s code is hard to maintain as it is currently written in wiki markup including parser functions, thus not allowing line breaks or additional white spaces.

My suggestion

  • Rewriting this template using Lua, based on a forum discussion.
  • Changing its defaults regarding the appearance of tool links.
  • Dropping uncommonly used features.

A documentation of my proposed changes is located at

Please feel free to comment your suggestions here or into the forum thread already used.