tag_condition_map - A schema to make checking for completeness of accessibility OSM-Data easier

This repository contains the file delfi_attributes.json, which can be used to check if accessibility-related OSM-Data on public transport stops is complete. It uses the DELFI-Handbook as the basis for what objects are checked for which attributes. Simply explained, it contains a list of conditions that connect objects that do have certain OSM-Tags (e.g. tags that mark an object as a public transport information office) to tags that these objects should have to be in compliance with DELFI (e.g. tags that mark an object as wheelchair accessible).

Schema

This section explains the schema according to which the delfi_attributes.json file is built and should be parsed.

The file is a List [] of Dictionaries {}. Each dictionary represents one DELFI-attribute that is checked for.

Every Dictionary must contain the following attributes:

DELFI_ID

An integer that represents the DELFI-ID of the attribute that is checked by this dictionary.

LABEL

A string that resembles the label as it is displayed in the DELFI-Handbook.

CONDITION

This describes preconditions that must be met before an element is checked for the presence of the actual values defined under TAGS.

The value can either be a CONDITION-dicionary or a list of CONDITION-dictionarys. In case of a list only one of the supplied CONDITION-dicionaries has to evaluate to true.

CONDITION-dictionary

A condition dictionary is a dictionary that can contain a number of keys. The value for those keys need ALL evaluate to true for the condition dictionary as a whole to be true. The keys are:

• osm_tags: A dictionary of OpenStreetMap-Keys and -values that all must be present for this sub-condition to be true. The keys are the OSM-Keys and the values are the OSM-Values. The values can be either a string, a list of strings, true or false. If the value is a list, the condition is true if any of the values in the list is present. If the value is true, the mere existence of the key is enough for the condition to be true. If the value is false, the condition is true if the key is not present.
• osm_element: A string that can be either Node, OpenWay, ClosedWay, Relation or a list of those strings. The condition is true if the element is of the type specified in the value. If the value is a list, the condition is true if the element is of any of the types specified in the list. If osm_element is not present, the condition is true for all element types.

TAGS

TAGS is a dictionary with OpenStreetMap-Keys as keys. Each key corresponds to a list of strings representing the expected values. If an empty list is supplied, the exact value of the key is indeterminate. If TAGS is empty, the mere existence of an element that was selected by the CONDITION is enough to pass the test.