# Source: https://gofastmcp.com/python-sdk/fastmcp-server-auth-redirect_validation.md

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# redirect_validation

# `fastmcp.server.auth.redirect_validation`

Utilities for validating client redirect URIs in OAuth flows.

## Functions

### `matches_allowed_pattern` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/redirect_validation.py#L8" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python  theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}}
matches_allowed_pattern(uri: str, pattern: str) -> bool
```

Check if a URI matches an allowed pattern with wildcard support.

Patterns support \* wildcard matching:

* [http://localhost](http://localhost):\* matches any localhost port
* [http://127.0.0.1](http://127.0.0.1):\* matches any 127.0.0.1 port
* https\://*.example.com/* matches any subdomain of example.com
* [https://app.example.com/auth/](https://app.example.com/auth/)\* matches any path under /auth/

**Args:**

* `uri`: The redirect URI to validate
* `pattern`: The allowed pattern (may contain wildcards)

**Returns:**

* True if the URI matches the pattern

### `validate_redirect_uri` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/auth/redirect_validation.py#L28" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python  theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}}
validate_redirect_uri(redirect_uri: str | AnyUrl | None, allowed_patterns: list[str] | None) -> bool
```

Validate a redirect URI against allowed patterns.

**Args:**

* `redirect_uri`: The redirect URI to validate
* `allowed_patterns`: List of allowed patterns. If None, all URIs are allowed (for DCR compatibility).
  If empty list, no URIs are allowed.
  To restrict to localhost only, explicitly pass DEFAULT\_LOCALHOST\_PATTERNS.

**Returns:**

* True if the redirect URI is allowed