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# Fetch Metadata Interceptor

## Description

Interceptor that implements Cross-Origin Embedder Policy on incoming requests.

COEP prevents the document from loading any framed documents which don’t opt-in by setting the COEP header. (`Cross-Origin-Embedder-Policy: require-corp`). This provides protection for documents that don’t restrict framing. A document that doesn’t set COEP cannot be framed by another document with COEP. All descendents of a document with COEP will also enforce the same restrictions.

COEP is now supported by all major browsers.

More information about COEP.

## Parameters

- `exemptedPaths` - Set of opt out endpoints that are meant to serve cross-site traffic. Paths should contain leading slashes and must be relative. This field is empty by default.
- `enforcingMode` - Boolean variable allowing the user to let COEP operate in `enforcing`, which blocks both resource and reports violations, or `report-only` mode, which only reports violations. Default value for field is `false`.
- `disabled` - Boolean variable disabling and enabling COEP. Default value for field is `false`.

## Examples

    <action  name="someAction" class="com.examples.SomeAction">
        <interceptor-ref name="defaultStack">
            <param name="coepInterceptor.exemptedPaths">/path1,/path2,/path3</param>
            <param name="coepInterceptor.enforcingMode">false</param>
            <param name="coepInterceptor.disabled">false</param>
        </interceptor-ref>
        <result name="success">good_result.ftl</result>
    </action>