[inference] propagate connector config to underlying adapter (elastic…

…#207202)

## Summary

Related to elastic#206710

Attach the `configuration` from the stack connector to the internal
`InferenceConnector` structure we're passing down to inference adapters.

This will allow the adapters to retrieve information from the stack
connector, which will be useful to introduce more provider specific
logic (for example, automatically detect if the underlying provider
supports native function calling or not).

This is also a requirement for the langchain bridge, as the chatModel
will need to know which type of provider is used under the hood.

x-pack/platform/packages/shared/ai-infra/inference-common/src/connectors.ts

@@ -19,10 +19,21 @@ export const COMPLETION_TASK_TYPE = 'chat_completion';
 
 const allSupportedConnectorTypes = Object.values(InferenceConnectorType);
 
+/**
+ * Represents a stack connector that can be used for inference.
+ */
 export interface InferenceConnector {
+  /** the type of the connector, see {@link InferenceConnectorType} */
   type: InferenceConnectorType;
+  /** the name of the connector */
   name: string;
+  /** the id of the connector */
   connectorId: string;
+  /**
+   * configuration (without secrets) of the connector.
+   * the list of properties depends on the connector type (and subtype for inference)
+   */
+  config: Record<string, string>;
 }
 
 /**

x-pack/platform/plugins/shared/inference/server/chat_complete/utils/inference_executor.test.ts

@@ -17,6 +17,7 @@ describe('createInferenceExecutor', () => {
     connectorId: 'foo',
     name: 'My Connector',
     type: InferenceConnectorType.OpenAI,
+    config: {},
   };
 
   beforeEach(() => {

x-pack/platform/plugins/shared/inference/server/routes/connectors.ts

@@ -49,6 +49,7 @@ export function registerConnectorsRoute({
             connectorId: connector.id,
             name: connector.name,
             type: connector.actionTypeId as InferenceConnectorType,
+            config: connector.config ?? {},
           };
         });
 

x-pack/platform/plugins/shared/inference/server/test_utils/inference_connector.ts

@@ -14,6 +14,7 @@ export const createInferenceConnectorMock = (
     type: InferenceConnectorType.OpenAI,
     name: 'Inference connector',
     connectorId: 'connector-id',
+    config: {},
     ...parts,
   };
 };

x-pack/platform/plugins/shared/inference/server/util/get_connector_by_id.test.ts

@@ -78,6 +78,10 @@ describe('getConnectorById', () => {
         id: 'my-id',
         name: 'My Name',
         actionTypeId: InferenceConnectorType.OpenAI,
+        config: {
+          propA: 'foo',
+          propB: 42,
+        },
       })
     );
 
@@ -87,6 +91,10 @@ describe('getConnectorById', () => {
       connectorId: 'my-id',
       name: 'My Name',
       type: InferenceConnectorType.OpenAI,
+      config: {
+        propA: 'foo',
+        propB: 42,
+      },
     });
   });
 });

x-pack/platform/plugins/shared/inference/server/util/get_connector_by_id.ts

@@ -43,5 +43,6 @@ export const getConnectorById = async ({
     connectorId: connector.id,
     name: connector.name,
     type: connector.actionTypeId,
+    config: connector.config ?? {},
   };
 };