GeorepositoryClient

class geodetic_engine.georepository.GeorepositoryClient

Bases: object

Reads objects from a Georepository instance.

Example

>>> client = GeorepositoryClient(config)
>>> systems = list(
...     client.iter_collection("GeodeticCoordRefSystem")
... )

__init__(config, *, credential=None, transport=None)

close()

Close the HTTP connection pools.

Return type:

None

get_object(url)

Fetch a single object by absolute URL, caching the result.

Scope, extent, unit and method objects are referenced by many parents; without caching the same object is refetched hundreds of times.

Parameters:

url (str) – Absolute URL, typically taken from a Links or href field.

Return type:

dict[str, Any]

Returns:

The decoded JSON object.

resolve(link)

Follow a ChildLink-shaped reference.

Parameters:

link (dict[str, Any] | None) – A mapping with an href key, or None.

Return type:

dict[str, Any]

Returns:

The referenced object, or an empty mapping when there is no link. An empty mapping is returned only for an absent link; a link that cannot be fetched raises.

self_href(item)

Return the canonical URL of an object, if it advertises one.

Parameters:

item (dict[str, Any]) – An object as returned by the API, with a Links array.

Return type:

str | None

Returns:

The self link, else the first link, else None.

aliases(item)

Fetch the alias records of an object.

Every object type exposes {object}/alias. The detail representation sometimes carries an inline Alias array as well; that is preferred when present to avoid a round trip.

Parameters:

item (dict[str, Any]) – A detail object carrying Links and possibly Alias.

Return type:

list[dict[str, Any]]

Returns:

Details-shaped alias records, each with Alias and NamingSystem. An empty list when the object has no aliases.

detail(item)

Fetch the full object behind a search result.

Collection endpoints return summaries; the fields needed to build a proj.db row only appear on the detail representation.

Parameters:

item (dict[str, Any]) – A search result carrying a Links array.

Return type:

dict[str, Any]

Returns:

The full object, or the input unchanged when it carries no link.

wkt(item)

Export an object as WKT2.

The register’s own rendering is used rather than one rebuilt from the object’s fields, so that a CRS this workflow does not model in full still reaches PROJ exactly as the authority stated it.

Parameters:

item (dict[str, Any]) – A detail object carrying Links.

Return type:

str | None

Returns:

The WKT string, or None when the object advertises no link or the instance returns an empty body.

Raises:

GeorepositoryApiError – If the export request fails. A bound CRS is one such case: the endpoint exists but answers HTTP 501.

Example

>>> client.wkt(client.detail(item))
'GEOGCRS["ED50",DATUM[...'

iter_collection(endpoint, *, authorities=None)

Yield every object in a collection endpoint, page by page.

Parameters:

• endpoint (str) – Endpoint name such as Transformation.

• authorities (frozenset[str] | None, default: None) – If given, only yield objects whose DataSource matches one of these names, compared case-insensitively. The API offers no server-side equivalent.

Yields:

Search result objects in server order.

Raises:

PaginationTruncatedError – If the server advertises more results than were collected, or repeats a page, which indicates the page parameter was ignored.

versions(*, custom_authority=None)

The newest version of each dataset the register keeps.

A register versions two things separately and reports both on its own landing page: the EPSG dataset it carries, and the objects it defines itself. A version history entry states no DataSource, so the two series are told apart by code, EPSG’s running up from 1 and the register’s own from a fixed floor well above EPSG’s range.

Only the collection summaries are read, never the detail of each entry: there are hundreds of them, and a build needs this answer before it can decide anything else.

Parameters:

custom_authority (str | None, default: None) – Name to report the register’s own series under. Defaults to custom, since the register does not name it.

Return type:

dict[str, str]

Returns:

Version by dataset, such as {"EPSG" -- "12.053", "Example": "1.103"}. Empty when the instance exposes no version history.

latest_version()

Return the newest Georepository version name, for provenance.

Return type:

str | None

Returns:

The Name of the most recent version history entry, or None when the instance exposes no version history.