# IRPCVault.GetMetadataStructureVersion

Location: [gRPC API](https://developer.m-files.com/APIs/gRPC-API/index.md) > [Vault API](https://developer.m-files.com/APIs/gRPC-API/vault/index.md) > [Vault information](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/index.md)

HTML version: https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureVersion/

Badges: `Vault API / core` `read` `session or assertion` `idempotent`

Gets the version numbers of the vault's metadata structure and of its property definitions.

- **Service:** [Vault information](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/index.md) `MFiles.IRPCVault`
- **gRPC method:** `/MFiles.IRPCVault/GetMetadataStructureVersion`
- **HTTP (mf-http-grpc):** `POST /grpc/v1/get-metadata-structure-version`
- **Request:** [`GetMetadataStructureVersionRequest`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureVersion/index.md#request)
- **Response:** [`GetMetadataStructureVersionResponse`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureVersion/index.md#response)
- **Book and level:** Vault API, core
- **Kind:** read
- **Session:** Required: a session (mfiles-session-id-bin metadata) or a session assertion (x-mf-session-assertion metadata).
- **Idempotent:** yes
- **Returns metadata structure version:** no
- **Streaming:** none (unary)

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## Remarks

A cheap check for structure changes. `metadata_structure_version` is the same number that other
methods return in the `mfiles-metadata-version-bin` trailer. This method itself sends no
trailer.

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## Request: GetMetadataStructureVersionRequest

No fields.

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## Response: GetMetadataStructureVersionResponse

A structure that specifies the response type for the GetMetadataStructureVersion method.

> Nested message fields are expanded to depth 3; follow a type link for deeper levels and for the type's own page.

| Field | Type | Description |
|---|---|---|
| `metadata_structure_version` | `int32` | The vault's metadata structure version. When it differs from the value your cache was built with, refresh cached structure data. |
| `property_defs_version` | `int32` | The version of the vault's property definitions. |

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## Related methods

- [GetMetadataStructure](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructure/index.md): Gets the vault's real object types (not value lists), with icons, in one call.