Basic example

The following example does a STAC search and returns usable Stac objects (Stac assets URLs are signed).

from pystac_client import Client
from teledetection import sign_inplace

api = Client.open('https://api.stac.teledetection.fr', modifier=sign_inplace)
res = api.search(datetime="2022-01-01/2022-12-25", collections=["spot-6-7-drs"])
items = res.item_collection()  # List of items with signed assets HREFs

Note that you can also sign objects only when needed, for instance here after a simple STAC search:

api = Client.open('https://api.stac.teledetection.fr')  # no modifier here!
res = api.search(...)  # same arguments as before
items = res.item_collection()  # Items assets HREFs are not signed yet
sign_inplace(items[0])  # Item 0 assets HREFs are now signed !
another_signed_item = sign(items[1])  # Another way to sign with copy

This should be the privileged way when you don't need to sign every single asset HREF of the STAC objects you are crawling, because the signing request will slow things down.

Info

teledetection.sign_inplace() can also be applied directly on a particular pystac.item, pystac.collection, pystac.asset or any URL as str, with the same outcome in term of expiry.

Signed URLs expiry

The signed URLs for STAC objects assets are valid during 8 hours after teledetection.sign_inplace or teledetection.sign is called. You can change this duration changing the environment variable TLD_URL_DURATION (in seconds, up to 8 days).