Some reasoning for some of the technical decisions:

• I took very little inspiration from the shortener gem, mostly just for the URL identifier length and format
• I decided to take a slightly different approach solving this issue, i.e. storing all needed information about the link target rather than storing only the path to link to
  • I figured that if at some point Decidim URL formats change, that might cause a problem for the old short URLs, this should also work after such refactor
• I wanted to make the API as easy to use as possible, so take a look at the meetings directory and meetings index pages on how to create the short link

In short, if you want to create short links in any view:

• Add the following in the controller: helper Decidim::ShortLinkHelper
• Add the following to the view:

<p>Link to the current component (when within a component):</p>
<p><%= short_url %></p>
<p>Link to custom resource route with parameters:</p>
<p><%= short_url(route_name: "custom_route", params: { decidim: "is", pretty: "neat" }) %></p>

Both keyword arguments are optional and have the following meanings:

• route_name (optional) - If the route is something else than the current view, e.g. in this case calendar_url instead of meetings_url, provide this information in the route_name parameter without the _url suffix.
• params (optional) - Any extra parameters that you want to append to the end of the target URL, such as /custom_route?decidim=is&pretty=neat

If you don't provide the route_name parameter, the URL will be generated to one of the following resources in this order:

1. Current component when within a current component
2. Current participatory space when within a current participatory space
3. Current organization when within a current organization
4. The main application when none of the above conditions match

If you want to create a short URL to a specific resource in Decidim, such as a static page, a meeting, etc. you can also do that as follows:

# Link to a Decidim::StaticPage
static_page_short_url = Decidim::ShortLink.to(Decidim::StaticPage.first, "decidim").short_url
# Link to a Decidim::Meetings::Meeting within a participatory space
meeting = Decidim::Meetings::Meeting.first
meeting_short_url = Decidim::ShortLink.to(meeting, meeting.component.mounted_engine).short_url

Or alternatively, you could do the following from within the view:

<p>Link to a static page (from the static page itself):</p>
<p><%= short_url(route_name: "static_page", params: { id: @page.slug }) %></p>

<p>Link to a meeting (from the single meeting page):</p>
<p><%= short_url(route_name: "meeting", params: { id: meeting.id }) %></p>

<p>Link to the meetings calendar URL (from the meetings component):</p>
<p><%= short_url(route_name: "calendar", params: { filter: { some: "filter" } }) %></p>

@andreslucena This is ready for review.

Regarding the labels, this is a weird case where for fixing a bug we needed to implement a new feature, so I though "why no both?" 🤷🏽‍♂️

@andreslucena Thanks for the review, typos fixed in the code comments.