Add filter unit conversion

[jwalgran]

Overview

Prior to this commit filters did not take instance unit preferences into account. I have added a "preprocessing" method that we can pass the filter object through which converts any values before the filter object is passed off to be converted into a query.

I have decided to implement this conversion on the server side to prevent having to change both mobile apps and the web client.

Connects https://github.com/OpenTreeMap/otm-clients/issues/399 Depends on https://github.com/OpenTreeMap/otm-tiler/pull/118

Testing Instructions

Setup

• Create a new instance with the url name unit-convert-test and select the green infrastructure addon http://localhost:6060/create/
• Edit the green infrastructure settings. Enable rain barrels. Save. http://localhost:6060/unit-convert-test/management/green-infrastructure/
• Add 4 trees with diameters 2, 4, 6, and 8. http://localhost:6060/unit-convert-test/map/?m=addTree
• Add a rain barrel with a capacity of 50 gallons http://localhost:6060/unit-convert-test/map/?m=addResource&t=RainBarrel
  • Edit the instance units. Set Tree Diameter to centimeters and Rain Barrel capacity to liters. Save http://localhost:6060/unit-convert-test/management/units/
• Edit the search fields. Enable Rain barrel capacity. Save. http://localhost:6060/unit-convert-test/management/search-configuration/

Test

• Verify that an advanced search for diameter < 5 returns no results

  

• Verify that an advanced search for diameter between 10 and 20 returns 2 results

  

• Verify that and advanced search for rain barrel capacity < 60 returns no results

  

• Verify that and advanced search for rain barrel capacity between 180 and 190 returns 1 result

  

[coveralls]

Coverage increased (+0.02%) to 83.858% when pulling 7f036c5c5fb596fce32682077041a6666ee3ee15 on jw/units-fix into 999c499139557c320483235262d15e614fe245df on hotfix/2.19.1.