trustgraph/specs/api/paths/flow/objects.yaml

post:
  tags:
    - Flow Services
  summary: Objects query - GraphQL over knowledge graph
  description: |
    Query knowledge graph using GraphQL for object-oriented data access.

    ## Objects Query Overview

    GraphQL interface to knowledge graph:
    - **Schema-driven**: Predefined types and relationships
    - **Flexible queries**: Request exactly what you need
    - **Nested data**: Traverse relationships in single query
    - **Type-safe**: Strong typing with introspection

    Abstracts RDF triples into familiar object model.

    ## GraphQL Benefits

    Compared to triples query:
    - **Developer-friendly**: Objects instead of triples
    - **Efficient**: Get related data in one query
    - **Typed**: Schema defines available fields
    - **Discoverable**: Introspection for tooling

    ## Query Structure

    Standard GraphQL query format:
    ```graphql
    query OperationName($var: Type!) {
      fieldName(arg: $var) {
        subField1
        subField2
        nestedObject {
          nestedField
        }
      }
    }
    ```

    ## Variables

    Pass variables for parameterized queries:
    ```json
    {
      "query": "query GetPerson($id: ID!) { person(id: $id) { name } }",
      "variables": {"id": "https://example.com/person/alice"}
    }
    ```

    ## Error Handling

    GraphQL distinguishes:
    - **Field errors**: Invalid query, missing fields (in `errors` array)
    - **System errors**: Connection issues, timeouts (in `error` object)

    Partial data may be returned with field errors.

    ## Schema Definition

    Schema defines available types via config service.
    Use introspection query to discover schema.

  operationId: objectsQueryService
  security:
    - bearerAuth: []
  parameters:
    - name: flow
      in: path
      required: true
      schema:
        type: string
      description: Flow instance ID
      example: my-flow
  requestBody:
    required: true
    content:
      application/json:
        schema:
          $ref: '../../components/schemas/query/ObjectsQueryRequest.yaml'
        examples:
          simpleQuery:
            summary: Simple query
            value:
              query: |
                {
                  person(id: "https://example.com/person/alice") {
                    name
                    email
                  }
                }
              user: alice
              collection: research
          queryWithVariables:
            summary: Query with variables
            value:
              query: |
                query GetPerson($id: ID!) {
                  person(id: $id) {
                    name
                    email
                    knows {
                      name
                    }
                  }
                }
              variables:
                id: "https://example.com/person/alice"
              operation-name: GetPerson
          nestedQuery:
            summary: Nested relationship query
            value:
              query: |
                {
                  person(id: "https://example.com/person/alice") {
                    name
                    knows {
                      name
                      worksFor {
                        name
                        location
                      }
                    }
                  }
                }
  responses:
    '200':
      description: Successful response
      content:
        application/json:
          schema:
            $ref: '../../components/schemas/query/ObjectsQueryResponse.yaml'
          examples:
            successfulQuery:
              summary: Successful query
              value:
                data:
                  person:
                    name: Alice
                    email: alice@example.com
                    knows:
                      - name: Bob
                      - name: Carol
                extensions:
                  execution_time_ms: "42"
            queryWithFieldErrors:
              summary: Query with field errors
              value:
                data:
                  person:
                    name: Alice
                    email: null
                errors:
                  - message: Cannot query field 'nonexistent' on type 'Person'
                    path: ["person", "nonexistent"]
            systemError:
              summary: System error
              value:
                data: null
                error:
                  type: TIMEOUT_ERROR
                  message: Query execution timeout after 30s
    '401':
      $ref: '../../components/responses/Unauthorized.yaml'
    '500':
      $ref: '../../components/responses/Error.yaml'