fix(VastAICompute): use iso country code in offer

Author: DragonStuff

src/dstack/_internal/core/backends/vastai/compute.py

@@ -56,12 +56,46 @@ def __init__(self, config: VastAIConfig):
     def get_offers_by_requirements(
         self, requirements: Requirements
     ) -> List[InstanceOfferWithAvailability]:
+        def spot_filter(offer):
+            return not offer.instance.resources.spot
+
+        extra_filter = spot_filter
+
+        configured_regions = self.config.regions or []
+        if configured_regions:
+            normalized_exact_regions = {
+                r.strip() for r in configured_regions if isinstance(r, str) and r.strip()
+            }
+            iso_country_codes = {
+                r.strip().upper()
+                for r in configured_regions
+                if isinstance(r, str) and len(r.strip()) == 2 and r.strip().isalpha()
+            }
+
+            def region_accepts(offer):
+                region_value = (offer.region or "").strip()
+                if not region_value:
+                    return False
+                if region_value in normalized_exact_regions:
+                    return True
+                if "," in region_value:
+                    trailing_code = region_value.split(",")[-1].strip().upper()
+                    if trailing_code in iso_country_codes:
+                        return True
+                if len(region_value) == 2 and region_value.isalpha() and region_value.upper() in iso_country_codes:
+                    return True
+                return False
+
+            def combined_filter(offer):
+                return spot_filter(offer) and region_accepts(offer)
+
+            extra_filter = combined_filter
+
         offers = get_catalog_offers(
             backend=BackendType.VASTAI,
-            locations=self.config.regions or None,
             requirements=requirements,
             # TODO(egor-s): spots currently not supported
-            extra_filter=lambda offer: not offer.instance.resources.spot,
+            extra_filter=extra_filter,
             catalog=self.catalog,
         )
         offers = [