Filters.md

Each category can define a list of filters. This is an additional JSON value with the key "filter", e.g.:

{
    "query": {
        "13": "nwr[amenity]"
    },
    "filter": {
        "type": {
            "name": "{{ keyTrans('amenity') }}",
            "type": "select",
            "values": {
                "bar": {
                    "nwr[
                },
        }
    }
}

This defines a filter with the ID 'type' and the translated name of the key 'amenity'. It's of type 'select' and has several possible values.

Each filter can define the following values:

• name: Name of the filter. String, which can make use of twig functions, e.g. keyTrans as in the above example.
• type: A form type, e.g. 'text', 'select', 'radio', 'checkbox'
• values: Possible values. Can either be an array, an object or a html string with several <option> tags (even for radio and checkbox). See below for more information.
• valueName: if the values do not have names (resp. an <option> without text content), use this twig template to create a each name. Use {{ value }} for the current value.
• query: A twig template which builds a query from the selected value (if the value has not a query defined), e.g. nwr[amenity={{ value }}]. If not defined the query will be built from key (or the filter ID), op and the selected value.
• sort: Sort values by their name. Possible values: 'natsort' (default), false.
• key: If not overridden by query, use this key for searching. If not defined, use the filter's ID. Can also be an array with a list of keys. You can use wildcards too, e.g. "name:*" to query all localized name tags.
• op: operator to use (if not overridden by query):
  • '=' exact match (default)
  • '!=' any value but this
  • '~' regular expression, case sensitive
  • '~i' regular expression, case insensitive
  • '!~', '!~i' regular expression, negated
  • 'has' query in semicolon-separated lists like cuisine=kebap;noodles
  • 'has_key_value' query object with a tag with this key
  • 'strsearch' query string parts (e.g. "kai keb" would match "Kaiser Kebap") and query character variants (e.g. "cafe" would match "café").
• show_default: if true, this filter will be shown by default, others need to be added via the select box.
• placeholder: a text which is shown as placeholder (Twig enabled)
• emptyQuery: A Overpass filter query which is added, when no value is selected.

Values

Array

Values can either be an array, e.g.

[ "bar", "restaurant", ... ]

Object

Values can be an object, e.g.

{ "bar":
    {
        "name": "Bar",
        "query": "nwr[amenity=bar]"
    }
}

• Name is optional and can be created via valueName.
• Query is optional, it can be created from key (or filter id), op and the value.

Twig template

Values can be a twig template (string). It has access to the const part of the category. It can create a list of options:

{% for k in const %}
<option value="{{ k }}"></option>
{% endfor %}
<option value="restaurant" query="nwr[amenity=restaurant]">Restaurant</option>

• Name is generated from text content. If it is empty, it can be created via valueName.
• Query is optional, it can be created from key (or filter id), op and the value.