Feature Property JSON Null Replacement Tool

Description

Parse a properties object, record whether key exists as an own member, remove its old entry if present, and append the key with JSON null before serializing.

Feature properties and foreign members are JSON metadata, distinct from the geometry coordinates. Exact key operations and ID type checks can preserve useful distinctions, but do not independently authenticate records or validate an entire Feature.

Parse a properties object, record whether key exists as an own member, remove its old entry if present, and append the key with JSON null before serializing.

When to use this tool

Use Feature Property JSON Null Replacement when you need a literal GeoJSON metadata, identifier, or shallow-key operation.

How to use the tool and how it works

Enter propertiesJson, key. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read propertiesJson, existed. Inspect existed before interpreting the associated values.

Parse a properties object, record whether key exists as an own member, remove its old entry if present, and append the key with JSON null before serializing.^[1]

Input field	Meaning and units	Accepted input
propertiesJson	Properties Json	Required. Text; maximum UTF-16 length 8192.
key	Key	Required. Text; maximum UTF-16 length 8192.

Output field	Interpretation	Returned shape
propertiesJson	Properties Json	Required. Text; maximum UTF-16 length 8192.
existed	Existed	Required. Boolean.

json

{
  "input": {
    "propertiesJson": "{\"a\":1,\"b\":2}",
    "key": "a"
  },
  "output": {
    "propertiesJson": "{\"b\":2,\"a\":null}",
    "existed": true
  }
}

Limitations and assumptions

Null replaces the value rather than deleting the property. An absent key is added, nested values are untouched, and original byte formatting is not preserved.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.

Alternative or Complementary methods

Validate the complete Feature and its intended data model after editing. Preserve identifier precision and distinguish null values, absent members, collisions, and nested properties explicitly.

References

Calculation and input contract: geojson/feature-property-json-null-replacement — tool.io

Similar or alternative tools

Feature Property Empty State
Parse propertiesJson as null or a plain object.
Feature Properties Single Key Removal
Parse a properties object, test whether key exists as an own member, remove that exact top-level key if present, and serialize the remaining entries.