Add Support for Custom Filters

[JettChenT]

#551

[milesmcc]

This is very exciting! Looking forward to getting this merged. Some small issues I encountered while testing:

• It seems like filtering for unset attributes (at least in Incident Type) does not work correctly (a lot of incidents should be showing up in the screenshot below
• In the screenshot above, also note that the label in the list is None, but it shows up as [Unset] in the filter listing; could we unify these? (Of course, we need to also allow for filtering where the actual value is None or Unset; tricky design problem!)
• Right now, when you select a filter in the list, it'll show up as a tag when it is no longer selected regardless of whether you enter a value or not. That might confuse users. Could we instead make it so either 1) the tag does not show up if the user does not enter a value, or 2) the tag shows up the moment the user clicks the value in the filter list?
• Could we add a placeholder to the geolocation input that says Latitude, longitude?
• When no filters match the search, could we display a message that says "No filters found"? Gray text, either text-xl or text-sm based on whatever you think looks better.
• Let's be sure to use String.to_existing_atom everywhere; using String.to_atom can allow for DOS. For more info, see https://nietaki.com/2018/12/04/string-to-existing-atom-is-a-double-edged-sword/

[JettChenT]

Thanks for the review!

• For the different naming of [Unset] and None, it seems like it is set on purpose for the tag attribute at:

  atlos/platform/assets/js/app.js

  Line 267 in 9f2df58

  let name = data.text == "[Unset]" ? "None" : data.text;

  . Should I change "None" to "Unset" here?
• Applied the other suggestions in the main comment

[milesmcc]

Ah, I see, the [Unset]/none was not something you introduced. Can we update the way we initialize TomSelect so that it displays the [Unset] tag as None (not set)? If not, then perhaps we remove this special case and just display the value as [Unset] in both the dropdown and in the tag list. Seeing None in the dropdown and [Unset] in the tag list was a bad product decision.

You can also ofc keep that out of scope for this PR and make no change, as long as filtering to unset values functions properly.

[milesmcc]

So so close! Some small things:

When compiling, I get these errors:

warning: function input_validations/3 required by protocol Phoenix.HTML.FormData is not implemented (in module Phoenix.HTML.FormData.Platform.Material.GenericSet)
  lib/platform/material/generic_set.ex:19: Phoenix.HTML.FormData.Platform.Material.GenericSet (module)

warning: function to_form/4 required by protocol Phoenix.HTML.FormData is not implemented (in module Phoenix.HTML.FormData.Platform.Material.GenericSet)
  lib/platform/material/generic_set.ex:19: Phoenix.HTML.FormData.Platform.Material.GenericSet (module)

Could we resolve these?

Also, when I try to filter based on the date, I'm running into an issue where the date filter doesn't pop up after I select.

Once we get these resolved, I think we'll be able to merge! Thank you again for all your work.

[JettChenT]

Thanks for the review! Addressed the issues in the latest commit.

P.S. love the updated date entry UI!

[milesmcc]

I think we're good to go! I'll officially merge after our next release (should be within the next week or so) because this is a big PR and I want to make sure we don't accidentally break anything.

[JettChenT]

Awesome! Learned a lot working on this PR