Logging with OnRequestCompleted
editLogging with OnRequestCompleted
editWhen constructing the connection settings to pass to the client, you can pass a callback of type
Action<IApiCallDetails>
to the OnRequestCompleted
method that can eavesdrop every time a
response(good or bad) is received.
If you have complex logging needs this is a good place to add that in since you have access to both the request and response details.
In this example, we’ll use OnRequestCompleted
on connection settings to increment a counter each time
it’s called.
var counter = 0; var client = new ElasticClient(new AlwaysInMemoryConnectionSettings().OnRequestCompleted(r => counter++)); client.RootNodeInfo(); counter.Should().Be(1); await client.RootNodeInfoAsync(); counter.Should().Be(2);
Construct a client |
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Make a synchronous call and assert the counter is incremented |
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Make an asynchronous call and assert the counter is incremented |
OnRequestCompleted
is called even when an exception is thrown, so it can be used even if the client is
configured to throw exceptions
var counter = 0; var client = FixedResponseClient.Create( new { }, 500, connectionSettings => connectionSettings .ThrowExceptions() .OnRequestCompleted(r => counter++), productCheckSucceeds: false ); Assert.Throws<ElasticsearchClientException>(() => client.RootNodeInfo()); counter.Should().Be(1); await Assert.ThrowsAsync<ElasticsearchClientException>(async () => await client.RootNodeInfoAsync()); counter.Should().Be(2);
Configure a client with a connection that **always returns a HTTP 500 response |
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Always throw exceptions when a call results in an exception |
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Assert an exception is thrown and the counter is incremented |
Here’s an example using OnRequestCompleted()
for more complex logging
By default, the client writes directly to the request stream and deserializes directly from the response stream.
If you would also like to capture the request and/or response bytes,
you also need to set .DisableDirectStreaming()
to true
.
var list = new List<string>(); var connectionPool = new SingleNodeConnectionPool(new Uri("http://localhost:9200")); var settings = new ConnectionSettings(connectionPool, new InMemoryConnection()) .DefaultIndex("default-index") .DisableDirectStreaming() .OnRequestCompleted(apiCallDetails => { // log out the request and the request body, if one exists for the type of request if (apiCallDetails.RequestBodyInBytes != null) { list.Add( $"{apiCallDetails.HttpMethod} {apiCallDetails.Uri} " + $"{Encoding.UTF8.GetString(apiCallDetails.RequestBodyInBytes)}"); } else { list.Add($"{apiCallDetails.HttpMethod} {apiCallDetails.Uri}"); } // log out the response and the response body, if one exists for the type of response if (apiCallDetails.ResponseBodyInBytes != null) { list.Add($"Status: {apiCallDetails.HttpStatusCode}" + $"{Encoding.UTF8.GetString(apiCallDetails.ResponseBodyInBytes)}"); } else { list.Add($"Status: {apiCallDetails.HttpStatusCode}"); } }); var client = new ElasticClient(settings); var syncResponse = client.Search<object>(s => s .AllIndices() .Scroll("2m") .Sort(ss => ss .Ascending(SortSpecialField.DocumentIndexOrder) ) ); list.Count.Should().Be(2); var asyncResponse = await client.SearchAsync<object>(s => s .AllIndices() .Scroll("10m") .Sort(ss => ss .Ascending(SortSpecialField.DocumentIndexOrder) ) ); list.Count.Should().Be(4); list.Should().BeEquivalentTo(new[] { @"POST http://localhost:9200/_all/_search?typed_keys=true&scroll=2m {""sort"":[{""_doc"":{""order"":""asc""}}]}", @"Status: 200", @"POST http://localhost:9200/_all/_search?typed_keys=true&scroll=10m {""sort"":[{""_doc"":{""order"":""asc""}}]}", @"Status: 200" });
Here we use |
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Disable direct streaming so we can capture the request and response bytes |
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Perform some action when a request completes. Here, we’re just adding to a list, but in your application you may be logging to a file. |
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Make a synchronous call |
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Make an asynchronous call |
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Assert the list contains the contents written in the delegate passed to |
When running an application in production, you probably don’t want to disable direct streaming for all requests, since doing so will incur a performance overhead, due to buffering request and response bytes in memory. It can however be useful to capture requests and responses in an ad-hoc fashion, perhaps to troubleshoot an issue in production.
DisableDirectStreaming
can be enabled on a per-request basis for this purpose. In using this feature,
it is possible to configure a general logging mechanism in OnRequestCompleted
and log out
request and responses only when necessary
var list = new List<string>(); var connectionPool = new SingleNodeConnectionPool(new Uri("http://localhost:9200")); var settings = new ConnectionSettings(connectionPool, new InMemoryConnection()) .DefaultIndex("default-index") .OnRequestCompleted(apiCallDetails => { // log out the request and the request body, if one exists for the type of request if (apiCallDetails.RequestBodyInBytes != null) { list.Add( $"{apiCallDetails.HttpMethod} {apiCallDetails.Uri} " + $"{Encoding.UTF8.GetString(apiCallDetails.RequestBodyInBytes)}"); } else { list.Add($"{apiCallDetails.HttpMethod} {apiCallDetails.Uri}"); } // log out the response and the response body, if one exists for the type of response if (apiCallDetails.ResponseBodyInBytes != null) { list.Add($"Status: {apiCallDetails.HttpStatusCode}" + $"{Encoding.UTF8.GetString(apiCallDetails.ResponseBodyInBytes)}"); } else { list.Add($"Status: {apiCallDetails.HttpStatusCode}"); } }); var client = new ElasticClient(settings); var syncResponse = client.Search<object>(s => s .AllIndices() .Scroll("2m") .Sort(ss => ss .Ascending(SortSpecialField.DocumentIndexOrder) ) ); list.Count.Should().Be(2); var asyncResponse = await client.SearchAsync<object>(s => s .RequestConfiguration(r => r .DisableDirectStreaming() ) .AllIndices() .Scroll("10m") .Sort(ss => ss .Ascending(SortSpecialField.DocumentIndexOrder) ) ); list.Count.Should().Be(4); list.Should().BeEquivalentTo(new[] { @"POST http://localhost:9200/_all/_search?typed_keys=true&scroll=2m", @"Status: 200", @"POST http://localhost:9200/_all/_search?typed_keys=true&scroll=10m {""sort"":[{""_doc"":{""order"":""asc""}}]}", @"Status: 200" });