docs/python-sdk/fastmcp-server-auth-providers-in_memory.mdx

---
title: in_memory
sidebarTitle: in_memory
---

# `fastmcp.server.auth.providers.in_memory`

## Classes

### `InMemoryOAuthProvider` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L31" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


An in-memory OAuth provider for testing purposes.
It simulates the OAuth 2.1 flow locally without external calls.


**Methods:**

#### `get_client` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L65" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
get_client(self, client_id: str) -> OAuthClientInformationFull | None
```

#### `register_client` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L68" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
register_client(self, client_info: OAuthClientInformationFull) -> None
```

#### `authorize` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L76" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
authorize(self, client: OAuthClientInformationFull, params: AuthorizationParams) -> str
```

Simulates user authorization and generates an authorization code.
Returns a redirect URI with the code and state.


#### `load_authorization_code` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L129" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
load_authorization_code(self, client: OAuthClientInformationFull, authorization_code: str) -> AuthorizationCode | None
```

#### `exchange_authorization_code` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L142" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
exchange_authorization_code(self, client: OAuthClientInformationFull, authorization_code: AuthorizationCode) -> OAuthToken
```

#### `load_refresh_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L193" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
load_refresh_token(self, client: OAuthClientInformationFull, refresh_token: str) -> RefreshToken | None
```

#### `exchange_refresh_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L208" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
exchange_refresh_token(self, client: OAuthClientInformationFull, refresh_token: RefreshToken, scopes: list[str]) -> OAuthToken
```

#### `load_access_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L263" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
load_access_token(self, token: str) -> AccessToken | None
```

#### `verify_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L274" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
verify_token(self, token: str) -> AccessToken | None
```

Verify a bearer token and return access info if valid.

This method implements the TokenVerifier protocol by delegating
to our existing load_access_token method.

**Args:**
- `token`: The token string to validate

**Returns:**
- AccessToken object if valid, None if invalid or expired


#### `revoke_token` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/providers/in_memory.py#L331" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
revoke_token(self, token: AccessToken | RefreshToken) -> None
```

Revokes an access or refresh token and its counterpart.