The STS API authenticates the user by verifying the JWT provided in the request. However access to object storage resources are controlled via named IAM policies defined in the MinIO instance. Once authenticated via the STS API, the MinIO server applies one or more IAM policies to the generated credentials. MinIO's AssumeRoleWithWebIdentity implementation supports specifying IAM policies in two ways:

## Prerequisites

Install Dex by following [Dex Getting Started Guide](https://dexidp.io/docs/getting-started/)

### Start Dex

```

    /**
     * Sets the URL stream handler factory for the environment. This
     * allows specification of the factory used in creating underlying
     * stream handlers. This can be called once per JVM instance.
     *
     * @param factory
     *            The URL stream handler factory.
     */
    public static void setURLStreamHandlerFactory(final URLStreamHandlerFactory factory) {

  }

  final void clear() {
    clearCache();
    backingMap.clear();
  }

  @Nullable V get(Object key) {
    checkNotNull(key);
    V value = getIfCached(key);
    // TODO(b/192579700): Use a ternary once it no longer confuses our nullness checker.
    if (value == null) {
      return getWithoutCaching(key);
    } else {
      return value;
    }
  }

  final @Nullable V getWithoutCaching(Object key) {

```

> NOTE: As MinIO needs to use a claim attribute in JWT for its policy, you should configure it in casdoor as well. Currently, casdoor uses `tag` as a workaround for configuring MinIO's policy.

Once successfully set restart the MinIO instance.

```
mc admin service restart myminio
```

### Using WebIdentiy API

              <groupId>org.codehaus.plexus</groupId>
              <artifactId>plexus-io</artifactId>
              <!-- We need at least 3.5.1 to avoid https://github.com/codehaus-plexus/plexus-io/issues/109. Once we upgrade maven-jar-plugin itself to a version new enough to depend on 3.5.1 or higher, we can remove this override. -->
              <version>3.5.1</version>
            </dependency>
          </dependencies>

              <groupId>org.codehaus.plexus</groupId>
              <artifactId>plexus-io</artifactId>
              <!-- We need at least 3.5.1 to avoid https://github.com/codehaus-plexus/plexus-io/issues/109. Once we upgrade maven-jar-plugin itself to a version new enough to depend on 3.5.1 or higher, we can remove this override. -->
              <version>3.5.1</version>
            </dependency>
          </dependencies>

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

/// tip

This same technique applies to `Query`, `Cookie`, and `Header`. 😎

///

   * outside the stated safe range. Subclasses should override this method to provide generalized
   * escaping for code points if required.
   *
   * <p>Note that arrays returned by this method must not be modified once they have been returned.
   * However it is acceptable to return the same array multiple times (even for different input
   * characters).
   *
   * @param cp the Unicode code point to escape

* `seek(offset)`: Goes to the byte position `offset` (`int`) in the file.
    * E.g., `await myfile.seek(0)` would go to the start of the file.
    * This is especially useful if you run `await myfile.read()` once and then need to read the contents again.
* `close()`: Closes the file.

As all these methods are `async` methods, you need to "await" them.