c# - 如何检查是否建立了与 Elasticsearch 的连接？

Question

我想检查与 Elasticsearch 数据库的连接是否正常。换句话说，我想 ping Elasticsearch。当我执行下面的代码时，抛出了一个异常。

    public async Task<HealthCheckResult> Execute()
    {
        if (_configuration.Nodes?.Length == 0)
        {
            await Task.Delay(1);
            return new HealthCheckResult("Connection Failed - Missing elasticsearch connection string")
            {
                ChildResults = new List<HealthCheckResult>() {new HealthCheckResult()}
            };
        }

        var node = new Uri(_configuration.Nodes.First());


        try
        {
            var connectionPool = new SniffingConnectionPool(new[] {node});
            var settings = new ConnectionConfiguration(connectionPool);
            var client = new ElasticLowLevelClient(settings);
            client.IndicesExists<string>("applications");
        }
        catch (Exception exception)
        {
            return new HealthCheckResult(exception.Message)
            {
                ChildResults = new List<HealthCheckResult>() { new HealthCheckResult() }
            };
        }

        return new HealthCheckResult("Connection Passed")
        {
            ChildResults = new List<HealthCheckResult>() { new HealthCheckResult() }
        };
    }

当我执行上面的方法时，异常被抛出并且我得到这个消息:

Failed sniffing cluster state.

如何检查是否已建立与 Elasticsearch 的连接？

Answer 1

Nest IElasticClient 接口(interface)为此提供了一个Ping 方法