Product registry¶

The product registry provides declarative configuration for 23 final and rapid SP3/CLK products from 14 analysis centers (agency codes). Products are defined in TOML; no hardcoded URLs in the processing code. Every product was checked against the file listings of ESA GSSC and NASA CDDIS (2025-001 and 2026-244, checked 2026-10-05); just check-products repeats the check (see Checking the registry).

Product types¶

Final

Latency 14–21 days · Accuracy cm-level

Highest quality. Use for scientific research, reprocessing campaigns, and publication-quality VOD products.
Rapid

Latency 17–24 hours · Accuracy near-final (cm-level)

Available the following day. Use for near-real-time processing when final products have not yet been released.

Type	Latency	Orbit accuracy	Clock accuracy
Final	14–21 d	< 2.5 cm	< 75 ps
Rapid	17–24 h	< 2.5 cm	< 75 ps

Ultra-rapid, real-time and near-real-time products are not supported: they are issued several times a day, are partly predicted, and their file names carry the issue hour. The settings reject product_type: ultra-rapid.

Available products¶

Systems: G GPS, R GLONASS, E Galileo, C BeiDou, J QZSS, read from the SP3 header of 2026-09-01. A run drops the observations of satellites the product has no orbits for (warning sids_dropped_no_ephemeris, once per file), so those signals get no VOD: choose a product that covers the systems of your signal selection, or narrow the selection.

Code	Agency	Final	Rapid
COD	Center for Orbit Determination in Europe	GRECJ	GRE
EMR	Natural Resources Canada	G	GR
ESA	European Space Agency	GRECJ	GR
GFZ	GeoForschungsZentrum Potsdam	GRE	GRECJ
GRG	CNES	GEC	GEC
IAC	Information-Analytical Centre	GRECJ	–
IGS	International GNSS Service	G (NASA CDDIS only)	G
JAX	JAXA (multi-GNSS)	GRECJ	–
JGX	JAXA	GRE	GRE
JPL	Jet Propulsion Laboratory	GE	GE
MIT	Massachusetts Institute of Technology	GE	–
NGS	National Geodetic Survey	G, no clocks	–
SIO	Scripps Institution of Oceanography	G, no clocks	G, no clocks
USN	US Naval Observatory	–	G

canvod.auxiliary.list_products() lists them; the registry is the truth. The default, COD final, covers all five systems. Products without clock files can't be used with fetch_clock: true; a run, and canvodpy config validate, stops before any download if the configured product does not exist or has no clocks while fetch_clock is true, and names the closest products.

Several samplings per product

Agencies have changed the sampling of their files over the years (for example ESA rapid: 15 min SP3 and 5 min CLK in 2025, 5 min SP3 and 30 s CLK in 2026). The registry lists every sampling a product has been published with, and the readers try them in that order, locally and then on each server. The sampling of the file used is recorded in the sampling_rate attribute of the orbit dataset.

Servers and fallback

Products are downloaded from ESA GSSC (no account needed). NASA CDDIS is a fallback, tried when ESA fails, once credentials.nasa_earthdata_acc_mail holds the email of a free NASA Earthdata account. Products that only NASA CDDIS hosts need that account.

Usage¶

Look up a productIn a run

from canvod.auxiliary import get_product_spec

spec = get_product_spec("COD", "final")
spec.prefix  # "COD0MGXFIN"
spec.sp3_samplings  # ["05M"], tried in this order
spec.clk_samplings  # ["30S"]; [] if the product has no clocks
spec.systems  # "GRECJ"
spec.sp3_filenames("2025001")  # ["COD0MGXFIN_20250010000_01D_05M_ORB.SP3"]
[s.url for s in spec.ftp_servers]  # ESA first, then NASA CDDIS

Runs pick the product from the settings; no manual lookup is needed:

processing:
  aux_data:
    agency: COD
    product_type: final
    fetch_clock: false  # true: also CLK, which VOD does not use

To add satellite geometry to a dataset in your own code, use an ephemeris provider (see canvod-auxiliary).

Registry format¶

Products are declared in packages/canvod-auxiliary/src/canvod/auxiliary/products/products.toml, one [[products]] table each, with its servers in priority order:

[[products]]
agency = "COD"
type = "final"
prefix = "COD0MGXFIN"
sp3_sampling = ["05M"]
clk_sampling = ["30S"]
systems = "GRECJ"
description = "CODE final multi-GNSS"
ftp_path = "/gnss/products/{gps_week}/{file}"

[[products.ftp_servers]]
url = "ftp://gssc.esa.int"
priority = 1
description = "ESA GSSC"

[[products.ftp_servers]]
url = "ftps://gdc.cddis.eosdis.nasa.gov"
priority = 2
requires_auth = true
description = "NASA CDDIS"

type is final or rapid. Every file covers one day (01D).

Checking the registry¶

just check-products                    # 2025-001 and the day three weeks ago
just check-products 2025001 2026244    # chosen days (YYYYDOY)

The recipe lists each server's GPS-week directory once per day and looks up every product's SP3 file, and CLK file if it has clocks, under each of its samplings. It prints the file found per product and day, or, for a missing product, the files of that product the servers do have, and exits with 1 if any product is missing. NASA CDDIS is checked when the settings hold credentials.nasa_earthdata_acc_mail; otherwise products hosted only there are reported as skipped. Run it after editing products.toml, and from time to time: agencies rename products, change samplings, and stop publishing.

just test-network runs the same check for 2025-001 as tests, one per product, together with a real download of the COD final files and a run that downloads its own orbits and clocks (see Testing).