/// <summary>
        /// Synchronously creates a <see cref="PublisherClient"/>, applying defaults for all unspecified settings.
        /// </summary>
        /// <param name="endpoint">Optional <see cref="ServiceEndpoint"/>.</param>
        /// <param name="settings">Optional <see cref="PublisherSettings"/>.</param>
        /// <param name="credentials">Optional <see cref="ChannelCredentials"/>.</param>
        /// <returns>The created <see cref="PublisherClient"/>.</returns>
        public static PublisherClient Create(
            ServiceEndpoint endpoint       = null,
            PublisherSettings settings     = null,
            ChannelCredentials credentials = null)
        {
            Channel channel = ClientHelper.CreateChannel(endpoint ?? DefaultEndpoint, credentials);

            Publisher.PublisherClient grpcClient = new Publisher.PublisherClient(channel);
            return(new PublisherClientImpl(grpcClient, settings));
        }
        // Note: we could have parameterless overloads of Create and CreateAsync,
        // documented to just use the default endpoint, settings and credentials.
        // Pros:
        // - Might be more reassuring on first use
        // - Allows method group conversions
        // Con: overloads!

        /// <summary>
        /// Asynchronously creates a <see cref="PublisherClient"/>, applying defaults for all unspecified settings.
        /// </summary>
        /// <param name="endpoint">Optional <see cref="ServiceEndpoint"/>.</param>
        /// <param name="settings">Optional <see cref="PublisherSettings"/>.</param>
        /// <param name="credentials">Optional <see cref="ChannelCredentials"/>.</param>
        /// <returns>The task representing the created <see cref="PublisherClient"/>.</returns>
        public static async Task <PublisherClient> CreateAsync(
            ServiceEndpoint endpoint       = null,
            PublisherSettings settings     = null,
            ChannelCredentials credentials = null)
        {
            Channel channel = await ClientHelper.CreateChannelAsync(endpoint ?? DefaultEndpoint, credentials).ConfigureAwait(false);

            Publisher.PublisherClient grpcClient = new Publisher.PublisherClient(channel);
            return(new PublisherClientImpl(grpcClient, settings));
        }