# ListLogTypeSchemas parity mapping

Supported in:

This guide details the request and response mapping specifications and property parity analysis for migrating from the legacy Backstory Feed Management API (**`ListLogTypeSchemas`** ) to the modern Chronicle API (**`ListLogTypeSchemas`**).

## Protocol and mapping overview

| Feature | Legacy API (`ListLogTypeSchemas`) | Modern Chronicle API (`ListLogTypeSchemas`) |
|---|---|---|
| **HTTP method** | `GET` | `GET` |
| **Permissions** | Partner token or legacy API keys | `chronicle.googleapis.com/logTypeSchemas.list` |

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## Request payload field-by-field parity

The modern Chronicle API `ListLogTypeSchemasRequest` requires parent scoping.

| Legacy field (`ListLogTypeSchemasRequest`) | Modern field (`ListLogTypeSchemasRequest`) | Field type | Parity and migration notes |
|---|---|---|---|
| `parent` *(in HTTP path)* | `parent` *(in HTTP path)* | `string` | **Google Cloud scoping context:** Scopes the target under standard parent project instance folder bindings. Pattern: `projects/{project}/locations/{location}/instances/{instance_uuid}/feedSourceTypeSchemas/{feed_source_type}`. |
| `page_size` | `page_size` | `int32` | **Parity mapped:** Pagination page size limits (default 5000, max 10000). Rename to `pageSize` in JSON payloads. |
| `page_token` | `page_token` | `string` | **Parity mapped:** Paging resumption token. Rename to `pageToken` in JSON payloads. |

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## Response payload field-by-field parity

Both the legacy Backstory Feed Management API (`ListLogTypeSchemas`) and the modern Chronicle API (`ListLogTypeSchemas`) return pagination results with matching schema models. In the modern Chronicle API, returned log schemas are fully populated with field definitions.

| Legacy field (`ListLogTypeSchemasResponse` message) | Modern field (`ListLogTypeSchemasResponse` message) | Field type | Parity and migration notes |
|---|---|---|---|
| `log_type_schemas` | `log_type_schemas` | `repeated LogTypeSchema` | **Parity mapped / enriched:** Array list of log type schema definitions. In the modern API, this returns full schemas including details field alternatives. Rename to `logTypeSchemas` in JSON. |
| `next_page_token` | `next_page_token` | `string` | **Parity mapped:** Next page resumption token. Rename to `nextPageToken` in JSON. |

### Nested LogTypeSchema field parity

The fields mapping inside individual LogTypeSchema items is as follows:

| Legacy field (`FeedSchema.LogTypeSchema` message) | Modern field (`LogTypeSchema` message) | Field type | Parity and migration notes |
|---|---|---|---|
| `name` | `name` | `string` | Contains canonical Google Cloud resource path: `projects/{pr}/locations/{loc}/instances/{in}/feedSourceTypeSchemas/{st}/logTypeSchemas/{log_type}`. |
| `display_name` | `display_name` | `string` | Rename to `displayName` in JSON responses. |
| `log_type` | `log_type` | `string` | Rename to `logType` in JSON responses. |
| `read_only` | `read_only` | `bool` | Rename to `readOnly` in JSON. |
| `supporting_documentation` | `supporting_documentation` | `string` | Rename to `supportingDocumentation` in JSON. |
| `details_field_schemas` | `details_field_schemas` | `repeated DetailsFieldSchema` | Direct mapping of compatible field properties. In legacy list responses, this was empty/attenuated; in modern list responses, it is fully populated. Rename to `detailsFieldSchemas` in JSON. |
| `details_field_schema_alternatives` | `details_field_schema_alternatives` | `repeated DetailsFieldSchemaAlternative` | Direct mapping of alternative schema sets. In legacy list responses, this was empty/attenuated; in modern list responses, it is fully populated. Rename to `detailsFieldSchemaAlternatives` in JSON. |

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## Key differences between the Backstory and Chronicle APIs

- **Google Cloud project scoping integration:**
  - Scoped natively under parent project instance folder bindings.
- **Full vs. attenuated schema returns:**
  - In legacy backstory, `ListLogTypeSchemas` returned attenuated schemas (with empty field definitions), requiring a secondary call to `GetLogTypeSchema` to get details. In the modern Chronicle API, because `GetLogTypeSchema` was retired, `ListLogTypeSchemas` returns full, comprehensive schema descriptions directly.
- **Explicit paging token behavior:**
  - The Chronicle API provides standard Google Cloud paging checkpoint logic.