Logs not writing to ElasticSearch from Xamarin Applications

[alexmartinezm]

Does this issue relate to a new feature or an existing bug?

• Bug
• New Feature

What version of Serilog.Sinks.Elasticsearch is affected? Please list the related NuGet package.
v5.5.0

What is the target framework and operating system? See target frameworks & net standard matrix.

• netCore 1.0
• netCore 2.0
• 4.5.x
• 4.6.x
• 4.7

This happens in Specific Platfom: Xamarin.Android and Xamarin.iOS.

Please describe the current behavior?
When I set the configuration from a Console Application project, this is the following code I use:

var logger = new LoggerConfiguration()
                .MinimumLevel.Is(level)
                .WriteTo.AndroidLog()
                .WriteTo.Elasticsearch(new ElasticsearchSinkOptions(new Uri(GlobalUrLs.ElasticUrl))
                {
                    IndexFormat = "mobile"
                })
                .CreateLogger();

Using the same NuGet versions, I use the same code for my Xamarin Application, but it does not send any log to my Elastic's Server.

Please describe the expected behavior?
It should send the logs to Elastic, as it is working with the Console Application.

If the current behavior is a bug, please provide the steps to reproduce the issue and if possible a minimal demo of the problem
Inside a Cross-Platform project, copy the code below (where GlobalUrLs.ElasticUrl is a valid IP, such 192.168.1.20:9200):

var logger = new LoggerConfiguration()
 .MinimumLevel.Is(level)
 .WriteTo.AndroidLog()
.WriteTo.Elasticsearch(new ElasticsearchSinkOptions(new Uri(GlobalUrLs.ElasticUrl))
{
 IndexFormat = "mobile"
})
.CreateLogger();

Log some message using Serilog:
Log.Information("Testing Serilog from Xamarin Application.");

It should post the log to the server, but it does not.

[mivano]

Unfortunately, I m not experienced with Xamarin. Did you try enabling the selflog (https://github.com/serilog/serilog/wiki/Debugging-and-Diagnostics) capabilities of Serilog and see if it outputs some useful information there?

[alexmartinezm]

Hello @mivano,

I have enabled SelfLog and it was reporting a not implemented exception in System.Net.Http.HttpClientHandler.set_MaxConnectionsPerServer. After searching in "Issues" inside this repo, I found the solution setting ConnectionLimit to -1. Here is the updated function:

SelfLog.Enable(msg => Android.Util.Log.Debug("SelfLog Serilog", msg));

var logger = new LoggerConfiguration()
                .MinimumLevel.Is((LogEventLevel)level)
                .WriteTo.AndroidLog()
                .WriteTo.Elasticsearch(new ElasticsearchSinkOptions(new Uri(GlobalUrLs.ElasticUrl))
                {
                    ModifyConnectionSettings = config => config.ConnectionLimit(-1),
                    IndexFormat = "mobile"
                })
                .CreateLogger();

SelfLog.Enable(msg => Android.Util.Log.Debug("SelfLog Serilog", msg));

Even with these changes, my Xamarin Application is still unable to send Logs to my Elastic Server.

[alexmartinezm]

After the last update on my function, suddently a bulk was sent to my Elastic Server!
Thank you, @mivano.

[mivano]

Good to see it is solved. Make sure to flush when your application closes as it might still have items in the buffer and is unable to deliver when quitting too early.

[Cheesebaron]

This is still an issue.

It seems like the managed HttpClientHandler mono provides does not support setting MaxConnectionsPerServer and throws.

Somewhere inside of Elasticsearch.NET they write:

var handler = new HttpClientHandler()

This means, even switching to AndroidHttpClientHandler or NSUrlSessionHandler in project properties does not kick in.

A way to get around this is to provide your own HttpConnection in ModifyConnectionSettings in ElasticSearchOptions:

Log.Logger = configuration
    .WriteTo.Elasticsearch(
        new ElasticsearchSinkOptions(esUrl)
        {
            ModifyConnectionSettings = c =>
            {
                var connection = new MyHttpConnection(handler);
                var pool = new SingleNodeConnectionPool(esUrl);
                return new ConnectionConfiguration(pool, connection);
            },

Where MyHttpConnection overrides CreateHttpClientHandler()

[mivano]

thanks for the feedback. Maybe something to raise on the Elasticsearch repo?

[Cheesebaron]

@mivano I've done that here: elastic/elasticsearch-net#3415