CZML Format

Read and write Cesium CZML documents as one JSON packet per record.

Overview

Property	Value
Format id	czml
Class	CZMLIterable
Extensions	.czml
Read	Yes
Write	Yes
Extra	none (ijson optional for streaming arrays)
Maturity	experimental

Record shape

Each packet is a dict (document header, entities, etc.):

{"id": "document", "version": "1.0"}
{"id": "point-1", "position": {"cartographicDegrees": [...]}}

A bare JSON object is treated as a single-packet document. Writes emit a JSON array of packets.

Usage

from iterable import open_iterable

with open_iterable("scene.czml") as source:
    for packet in source:
        print(packet.get("id"))

with open_iterable("out.czml", mode="w", format="czml") as dest:
    dest.write({"id": "document", "version": "1.0"})
    dest.write({"id": "entity-1", "name": "Sample"})

Error Handling

• Missing dependency: optional libraries raise ImportError with an install hint (pip install 'iterabledata[<extra>]' when an extra exists).
• Write mode: read-only formats raise WriteNotSupportedError or ValueError when opened with mode="w".
• Bad or unsupported input: may raise ValueError, OSError, or library-specific errors.
• See Troubleshooting for decoding, detection, and engine issues.

See also

• GeoJSON — geospatial features
• KML — Keyhole Markup Language
• Supported formats

Parameters

Parameter	Type	Default	Required	Description
encoding	str	'utf-8'	No	Passed via iterableargs.