[Cosmos] Fix pkranges fetch: use container name for URL, RID for cache key

[tvaron3]

Summary

Fixes #4031 — the pkranges fetch was using the collection RID in a name-based URL hierarchy (dbs/perfdb/colls/<RID>/pkranges), which Cosmos DB rejects with 404 because mixed name/RID addressing is not supported.

The previous fix (#4041) corrected URL encoding (.item() → .item_by_rid()) but did not fix the fundamental mixed-addressing issue. This PR resolves it by passing the container name for URL construction while keeping the RID as the cache key and request context value.

Root Cause

PR #4005 changed container_connection.rs::send() to pass self.container_ref.rid() to pk_range_cache.try_lookup(). The cache used this RID to build the pkranges URL:

dbs/perfdb/colls/pLLZAIuPigw=/pkranges
     ^^^^^^       ^^^^^^^^^^^^^
     NAME          RID  ← mixed addressing → 404

All other SDK and driver operations use name-based URLs. The pkranges fetch was the only code path using a RID in a name-based link hierarchy.

Impact (observed on continuous benchmarks)

• 1.8M 404 requests/hour from failed pkranges fetches
• Errors silently swallowed by try_lookup → Ok(routing_map.ok())
• Errors not cached → retried on every request (write lock contention on AsyncCache)
• Loss of client-side partition key routing → gateway must route all requests
• Throughput regression from ~110M to ~4.2M requests/hour

Changes

partition_key_range_cache.rs

• Added collection_name: &str parameter to try_lookup, get_routing_map_for_collection, resolve_partition_key_range_by_id, and resolve_overlapping_ranges
• Changed .item_by_rid(collection_rid) → .item(collection_name) for pkranges URL construction
• Cache key remains the RID (collection_rid.to_string())
• resource_id on the request remains the RID
• Updated tracing::warn! to include both collection_name and collection_rid
• Replaced 3 RID-encoding unit tests with 2 tests verifying name-based URL construction

container_connection.rs

• Extracted collection_name from self.container_ref.name() alongside existing collection_rid
• Passes collection_name to all pk_range_cache method calls
• resolved_collection_rid on request context still uses the RID (unchanged)

cosmos_fault_injection.rs

• Added fault_injection_pkrange_readfeed_is_exercised integration test
• Injects a transient error on MetadataPartitionKeyRanges ReadFeed with hit_limit=1
• Verifies the fault rule is hit (proving pkrange fetch code path executes)
• Verifies subsequent item operations succeed (proving end-to-end pkrange resolution works)

Test Results

• ✅ 31 unit tests pass (including 2 new)
• ✅ Build succeeds
• Integration test requires emulator (will run in CI)

[github-actions]

API Change Check

APIView identified API level changes in this PR and created the following API reviews

azure_data_cosmos

[Copilot]

Pull request overview

Fixes Cosmos partition-key-ranges (pkranges) fetch failures caused by mixed name/RID addressing by using the container name for URL construction while continuing to use the container RID for cache keys and request context.

Changes:

• Updates PartitionKeyRangeCache APIs to accept collection_name for building name-based pkranges URLs while keeping RID-based cache keys.
• Updates ContainerConnection to pass both container name and RID into pk-range cache lookups.
• Extends fault injection to support “spy” passthrough status recording and adds an emulator test to assert the pkranges path is exercised and succeeds.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
sdk/cosmos/azure_data_cosmos/src/routing/partition_key_range_cache.rs	Build pkranges links with container name (not RID) while keeping RID as cache key/context; update unit tests accordingly.
sdk/cosmos/azure_data_cosmos/src/handler/container_connection.rs	Pass container name + RID into pk-range cache calls during request routing.
sdk/cosmos/azure_data_cosmos/src/fault_injection/rule.rs	Add storage/access for passthrough response status codes on matched “spy” rules.
sdk/cosmos/azure_data_cosmos/src/fault_injection/http_client.rs	Record real service response status codes for matched passthrough (spy) rules.
sdk/cosmos/azure_data_cosmos/tests/emulator_tests/cosmos_fault_injection.rs	Add emulator test covering the pkranges readfeed path via a spy rule and validating it returns 200.