Quicktour¶

Installation¶

pip install ccsds-ndm-py

cargo add ccsds-ndm

Parsing Messages¶

Constructing Messages

Build a small complete message from explicit metadata and caller data, then generate valid output. Generation validates the complete message before writing.

import ccsds_ndm
from ccsds_ndm import OdmHeader, Opm, OpmData, OpmMetadata, OpmSegment, StateVector

header = OdmHeader("2023-01-01T00:00:00", "TEST")
meta = OpmMetadata(
    object_name="SAT1",
    object_id="2023-001A",
    center_name="EARTH",
    ref_frame="GCRF",
    time_system="UTC",
)
state = StateVector(
    epoch="2023-01-01T00:00:00",
    x=7000.0, y=0.0, z=0.0, x_dot=0.0, y_dot=7.5, z_dot=0.0,
    comment=None,
)
opm = Opm(
    header=header,
    segment=OpmSegment(metadata=meta, data=OpmData(state_vector=state, comment=[])),
)
opm.to_file("output.opm", "kvn")

use ccsds_ndm::messages::opm::{Opm, OpmBody, OpmData, OpmMetadata, OpmSegment};

// See ccsds-ndm/examples/builder_demo.rs for a minimal state-vector OPM
// built with public builders, then validated generation with to_kvn()/to_xml().

Generic Parsing

Use the top-level functions when you want to handle any message type dynamically.

import ccsds_ndm

# Returns an Oem, Opm, etc.
ndm = ccsds_ndm.from_file("example.oem")

use ccsds_ndm::from_file;

let ndm = from_file("example.oem")?;

Type-Specific Parsing

If you know the file type (e.g., OPM), you can parse it directly into the struct.

import ccsds_ndm
from ccsds_ndm import Opm

# Returns an Opm object directly
opm = Opm.from_file("example.opm")

use ccsds_ndm::messages::opm::Opm;
use ccsds_ndm::Ndm;
use std::fs;

let text = fs::read_to_string("example.opm")?;
// Parses strict KVN for OPM
let opm = Opm::from_kvn(&text)?;

Data Access¶

Once parsed, you can access the nested data structures.

# Assuming 'ndm' is an Oem object
for segment in ndm.segments:
    meta = segment.metadata
    print(f"Object: {meta.object_name} ({meta.object_id})")

    # State vectors are in segment.data.state_vector
    for sv in segment.data.state_vector:
        print(f"Epoch: {sv.epoch}, X: {sv.x}")

use ccsds_ndm::Message;

if let Message::Oem(oem) = ndm {
    for segment in oem.body.segment {
        let meta = segment.metadata;
        println!("Object: {} ({})", meta.object_name, meta.object_id);

        // State vectors are in segment.data.state_vector
        for sv in segment.data.state_vector {
            println!("Epoch: {}, X: {}", sv.epoch, sv.x);
        }
    }
}

Writing Messages¶

You can convert the in-memory structures back to KVN or XML.

# Convert to XML string
xml_string = ndm.to_str("xml")

# Write to KVN file
ndm.to_file("output.kvn", "kvn")

// Convert to XML string
let xml_string = ndm.to_xml()?;

// Write to KVN file
ndm.to_kvn_file("output.kvn")?;