grpc/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs

#region Copyright notice and license

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// modification, are permitted provided that the following conditions are
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//
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//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
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#endregion

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

using Grpc.Core.Internal;
using Grpc.Core.Utils;

namespace Grpc.Core
{
    /// <summary>
    /// Asynchronous authentication interceptor for <see cref="CallCredentials"/>.
    /// </summary>
    /// <param name="context">The interceptor context.</param>
    /// <param name="metadata">Metadata to populate with entries that will be added to outgoing call's headers.</param>
    /// <returns></returns>
    public delegate Task AsyncAuthInterceptor(AuthInterceptorContext context, Metadata metadata);

    /// <summary>
    /// Context for an RPC being intercepted by <see cref="AsyncAuthInterceptor"/>.
    /// </summary>
    public class AuthInterceptorContext
    {
        readonly string serviceUrl;
        readonly string methodName;

        /// <summary>
        /// Initializes a new instance of <c>AuthInterceptorContext</c>.
        /// </summary>
        public AuthInterceptorContext(string serviceUrl, string methodName)
        {
            this.serviceUrl = Preconditions.CheckNotNull(serviceUrl);
            this.methodName = Preconditions.CheckNotNull(methodName);
        }

        /// <summary>
        /// The fully qualified service URL for the RPC being called.
        /// </summary>
        public string ServiceUrl
        {
            get { return serviceUrl; }
        }

        /// <summary>
        /// The method name of the RPC being called.
        /// </summary>
        public string MethodName
        {
            get { return methodName; }
        }
    }
}