Ajm/fix 2585 ignore missing lexical

[amorton]

What this PR does:

If the user does not explicit (by using $lexcial) request a lexical leg for findAndRerank and the collection does not have a lexical index do not return an error. We only return an error if the user actually asks for lexical and they do not have one.

Added unit tests, verified via API below:

Create collection with lexcial and rerank disabled:

{
    "createCollection": {
        "name": "rerank_no_lexical",
        "options": {
            "vector": {
                "metric": "cosine",
                "dimension": 1024,
                "service": {
                    "provider": "openai",
                    "modelName": "text-embedding-3-small"
                }
            },
            "lexical": {
                "enabled": false
            },
					"rerank": {
                "enabled": false
            }
        }
    }
}

Try findAndRerank without model override fails as expected:

{
    "findAndRerank": {
        "filter": {},
        "projection": {},
        "sort": {
            "$hybrid": "I like cheese!"
        },
        "options": {
            "limit": 20,
            "includeScores": true,
            "includeSortVector": false
        }
    }
}

{
	"errors": [
		{
			"id": "ebab6334-2f9a-4003-a2fe-c1f5f093f207",
			"family": "REQUEST",
			"scope": "SCHEMA",
			"errorCode": "RERANKING_FEATURE_NOT_ENABLED",
			"title": "Reranking feature not enabled",
			"message": "Reranking feature is not enabled for this database."
		}
	]
}

Then with a model override, the command tries to execute and sees it needs an embedding key (because open AI was used). This means it started running the command:

{
	"findAndRerank": {
		"filter": {},
		"projection": {},
		"sort": {
			"$hybrid": "I like cheese!"
		},
		"options": {
			"limit": 20,
			"includeScores": true,
			"includeSortVector": false,
			"rerank": {
				"provider": "nvidia",
				"modelName": "nvidia/llama-3.2-nv-rerankqa-1b-v2"
			}
		}
	}
}

{
	"errors": [
		{
			"id": "076fa39c-1d7b-480a-9d56-8657328799e9",
			"family": "SERVER",
			"scope": "EMBEDDING_PROVIDER",
			"errorCode": "EMBEDDING_PROVIDER_AUTHENTICATION_KEYS_NOT_PROVIDED",
			"title": "Authentication header(s) missing from embedding request",
			"message": "Missing authentication header(s) from embedding request (provider 'openai'): 'x-embedding-api-key' header is missing')."
		}
	]
}

In attached full trace running the command above that failed...

trace.json

Confirmed that the resolver only added one inner read, not 2:

"innerTaskGroup": {
	"TaskGroup": {
		"groupId": "e5d0c98a-9fa5-4254-9a40-0dbb00235a8e",
		"taskType": "IntermediateCollectionReadTask",
		"sequentialProcessing": false,
		"size": 1.0,
		"statusCount": "{READY=1}",
		"tasks": [
			{
				"IntermediateCollectionReadTask": {
					"position": 1.0,
					"status": "READY",
					"taskId": "5b846d15-162f-4f29-814e-eba48481e699",
					"schemaObject.type": "COLLECTION",
					"schemaObject.name": {
						"SchemaObjectIdentifier": {
							"tenant": {
								"Tenant": {
									"tenantId": "SINGLE-TENANT",
									"databaseType": "CASSANDRA",
									"region": "CASSANDRA_REGION"
								}
							},
							"type": "COLLECTION",
							"keyspace": "default_keyspace",
							"table": "rerank_no_lexical"
						}
					},

Which issue(s) this PR fixes:
Fixes #2585

Checklist

• Changes manually tested
• Automated Tests added/updated
• Documentation added/updated
• CLA Signed: DataStax CLA

[github-actions]

📈 Unit Test Coverage Delta vs Main Branch

Metric	Value
Main Branch	54.12%
This PR	54.56%
Delta	🟢 +0.44%
✅ Coverage improved!

[github-actions]

Unit Test Coverage Report

Overall Project	54.56%	🍏
Files changed	96.43%	🍏

File	Coverage
FindAndRerankSortClauseDeserializer.java	99.46%	🍏
FindAndRerankOperationBuilder.java	93.55% -0.26%	🍏
CommandFeatures.java	82.68%	🍏

[erichare]

One test that i believe needs to be updated, to address the DSE integration failure. Otherwise looks fantastic.

[Hazel-Datastax]

lgtm

[erichare]

LGTM

[github-actions]

📈 Integration Test Coverage Delta vs Main Branch (dse69-it)

Metric	Value
Main Branch	71.99%
This PR	72.03%
Delta	🟢 +0.04%
✅ Coverage improved!

[github-actions]

Integration Test Coverage Report (dse69-it)

Overall Project	72.03%	🍏
Files changed	91.07%	🍏

File	Coverage
FindAndRerankOperationBuilder.java	88.29% -0.66%	🍏
CommandFeatures.java	73.23%	🍏
FindAndRerankSortClauseDeserializer.java	57.91%	🍏

[github-actions]

📈 Integration Test Coverage Delta vs Main Branch (hcd-it)

Metric	Value
Main Branch	73.26%
This PR	73.27%
Delta	🟢 +0.02%
✅ Coverage improved!

[github-actions]

Integration Test Coverage Report (hcd-it)

Overall Project	73.27%	🍏
Files changed	91.07%	🍏

File	Coverage
FindAndRerankOperationBuilder.java	91.84% -0.66%	🍏
CommandFeatures.java	73.23%	🍏
FindAndRerankSortClauseDeserializer.java	57.91%	🍏