Amazon CloudWatch Client
You can use Amazon CloudWatch Logs to monitor, store, and access your log files from Amazon Elastic Compute Cloud (Amazon EC2) instances, AWS CloudTrail, Route 53, and other sources.
You can find more information about CloudWatch at the AWS CloudWatch Logs website.
| The CloudWatch Logs extension is based on AWS Java SDK 2.x. It’s a major rewrite of the 1.x code base that offers two programming models (Blocking & Async). |
The Quarkus extension supports two programming models:
-
Blocking access using URL Connection HTTP client (by default) or the Apache HTTP Client
-
Asynchronous programming based on JDK’s
CompletableFutureobjects and the Netty HTTP client (by default) or the AWS CRT-based HTTP client
In this guide, we see how you can get your REST services to use CloudWatch Logs locally and on AWS.
Prerequisites
To complete this guide, you need:
-
JDK 17+ installed with
JAVA_HOMEconfigured appropriately -
an IDE
-
Apache Maven 3.8.1+
-
An AWS Account to access the CloudWatch service
-
Docker for your system to run CloudWatch locally for testing purposes
Provision CloudWatch locally via Dev Services
The easiest way to start working with CloudWatch Logs is to run a local instance using Dev Services.
Provision CloudWatch Manager locally manually
You can also set up a local version of CloudWatch Logs manually, first start a LocalStack container:
docker run --rm --name local-cloudwatchlogs --publish 4566:4582 -e SERVICES=logs -e START_WEB=0 -d localstack/localstack:3.0.1This starts CloudWatch instance that is accessible on port 4566.
Create an AWS profile for your local instance using AWS CLI:
$ aws configure --profile localstack
AWS Access Key ID [None]: test-key
AWS Secret Access Key [None]: test-secret
Default region name [None]: us-east-1
Default output format [None]:Solution
The application built here allows creating a log group and log stream and push logs events to it.
We recommend that you follow the instructions in the next sections and create the application step by step. However, you can go right to the completed example.
Clone the Git repository: git clone https://github.com/quarkusio/quarkus-quickstarts.git, or download an archive.
The solution is located in the amazon-cloudwatchlogs-quickstart directory.
Creating the Maven project
First, we need a new project. Create a new project with the following command:
mvn io.quarkus.platform:quarkus-maven-plugin:3.15.0:create \
-DprojectGroupId=org.acme \
-DprojectArtifactId=amazon-cloudwatchlogs-quickstart \
-DclassName="org.acme.cloudwatchlogs.QuarkusCloudWatchLogsSyncResource" \
-Dpath="/sync" \
-Dextensions="resteasy,resteasy-jackson,amazon-cloudwatchlogs,resteasy-mutiny"
cd amazon-cloudwatchlogs-quickstartThis command generates a Maven structure importing the RESTEasy/JAX-RS, Mutiny and Amazon CloudWatch Client extensions.
After this, the amazon-cloudwatchlogs extension has been added to your pom.xml as well as the Mutiny support for RESTEasy.
Creating JSON REST service
In this example, we will create an application that allows us to create a log group and log stream and push logs events to it using CloudWatch Logs using a RESTful API. The example application will demonstrate the two programming models supported by the extension.
Let’s start with an abstract org.acme.cloudwatchlogs.QuarkusCloudWatchLogsResource class to provide the common functionality we will need for both the synchronous and asynchronous exposures.
package org.acme.cloudwatchlogs;
import software.amazon.awssdk.services.cloudwatchlogs.model.*;
import java.time.Instant;
public abstract class QuarkusCloudWatchLogsResource {
protected CreateLogStreamRequest generateCreateLogStreamRequest(String groupName, String streamName) {
return CreateLogStreamRequest.builder()
.logGroupName(groupName)
.logStreamName(streamName).build(); (1)
}
protected DescribeLogGroupsRequest generateDescribeLogGroupRequest(String groupName) {
return DescribeLogGroupsRequest.builder()
.logGroupNamePattern(groupName).build(); (2)
}
protected CreateLogGroupRequest generateCreateLogGroupRequest(String groupName) {
return CreateLogGroupRequest.builder().logGroupName(groupName).build(); (3)
}
protected PutLogEventsRequest generatePutLogEventRequest(String groupName, String streamName, String logMessage) {
return PutLogEventsRequest.builder().logGroupName(groupName).logStreamName(streamName)
.logEvents(InputLogEvent.builder().message(logMessage)
.timestamp(Instant.now().toEpochMilli()).build()).build(); (4)
}
protected GetLogEventsRequest generateGetLogEvents(String groupName, String streamName) {
return GetLogEventsRequest.builder()
.logGroupName(groupName).logStreamName(streamName)
.build(); (5)
}
}| 1 | Generate a request to create a log stream for a specific group |
| 2 | Generate a request to list created log groups |
| 3 | Generate a request to create a log group |
| 4 | Generate a request put log events at a specific log stream and group |
| 5 | Generate a request to list all log events for a specific log stream and group |
Now, we can extend the class and create the synchronous implementation in the org.acme.cloudwatchlogs.QuarkusCloudWatchLogsSyncResource class.
package org.acme.cloudwatchlogs;
import io.quarkus.logging.Log;
import jakarta.inject.Inject;
import jakarta.ws.rs.*;
import jakarta.ws.rs.core.MediaType;
import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient;
import software.amazon.awssdk.services.cloudwatchlogs.model.*;
import java.util.List;
import java.util.stream.Collectors;
@Path("/sync")
public class QuarkusCloudWatchLogsSyncLogsResource extends QuarkusCloudWatchLogsResource {
@Inject (1)
CloudWatchLogsClient client;
@GET
@Produces(MediaType.TEXT_PLAIN)
public String listLogEventsOfStream(@QueryParam("groupName") String groupName,
@QueryParam("streamName") String streamName) {
Log.info("List Logs for " + groupName + " - " + streamName);
List<String> messages = client.getLogEventsPaginator(
generateGetLogEvents(groupName, streamName)
).stream()
.flatMap(getLogEventsResponse -> getLogEventsResponse.events().stream())
.map(OutputLogEvent::message)
.collect(Collectors.toList());
return String.join("\n", messages);
}
@POST
@Produces(MediaType.TEXT_PLAIN)
public String createLogStream(@FormParam("groupName") String groupName,
@FormParam("streamName") String streamName) {
Log.info("Create Log Stream for " + groupName + " - " + streamName);
try {
client.createLogGroup(generateCreateLogGroupRequest(groupName));
} catch (ResourceAlreadyExistsException e) {
Log.info("Log Group Already Exists " + groupName);
}
//There is a slight delay between the creation and it being available
boolean logGroupCreated = false;
while (!logGroupCreated) {
logGroupCreated = client.describeLogGroups(generateDescribeLogGroupRequest(groupName))
.logGroups()
.stream()
.anyMatch(logGroup -> logGroup.logGroupName().equals(groupName));
}
client.createLogStream(generateCreateLogStreamRequest(groupName, streamName));
return "OK";
}
@PUT
@Produces(MediaType.TEXT_PLAIN)
public String putLogEventsForStream(@FormParam("groupName") String groupName,
@FormParam("streamName") String streamName,
@FormParam("message") String message) {
Log.info("Put Log Event for " + groupName + " - " + streamName);
client.putLogEvents(generatePutLogEventRequest(groupName, streamName, message));
return "OK";
}
}| 1 | Inject the client provided by the amazon-cloudwatchlogs-logs extension |
Using the Amazon CloudWatch Logs SDK, we can get & push log data to CloudWatch Logs Stream.
Configuring CloudWatch Logs clients
Both CloudWatch Logs clients (sync and async) are configurable via the application.properties file that can be provided in the src/main/resources directory.
Additionally, you need to add to the classpath a proper implementation of the sync client. By default the extension uses the URL connection HTTP client, so
you need to add a URL connection client dependency to the pom.xml file:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>url-connection-client</artifactId>
</dependency>If you want to use the Apache HTTP client instead, configure it as follows:
quarkus.cloudwatchlogs.sync-client.type=apacheAnd add the following dependency to the application pom.xml:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>apache-client</artifactId>
</dependency>If you want to use the AWS CRT-based HTTP client instead, configure it as follows:
quarkus.cloudwatchlogs.sync-client.type=aws-crtAnd add the following dependency to the application pom.xml:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>aws-crt-client</artifactId>
</dependency>If you’re going to use a local CloudWatch Logs instance, configure it as follows:
quarkus.cloudwatchlogs.endpoint-override=http://localhost:4566 (1)
quarkus.cloudwatchlogs.aws.region=us-east-1 (2)
quarkus.cloudwatchlogs.aws.credentials.type=static (3)
quarkus.cloudwatchlogs.aws.credentials.static-provider.access-key-id=test-key
quarkus.cloudwatchlogs.aws.credentials.static-provider.secret-access-key=test-secret| 1 | Override the CloudWatch client to use LocalStack instead of the actual AWS service |
| 2 | Localstack defaults to us-east-1 |
| 3 | The static credentials provider lets you set the access-key-id and secret-access-key directly |
If you want to work with an AWS account, you can simply remove or comment out all Amazon CloudWatch related properties. By default, the CloudWatch client extension will use the default credentials provider chain that looks for credentials in this order:
-
Java System Properties -
aws.accessKeyIdandaws.secretAccessKey -
Environment Variables -
AWS_ACCESS_KEY_IDandAWS_SECRET_ACCESS_KEY -
Credential profiles file at the default location (
~/.aws/credentials) shared by all AWS SDKs and the AWS CLI -
Credentials delivered through the Amazon ECS if the
AWS_CONTAINER_CREDENTIALS_RELATIVE_URIenvironment variable is set and the security manager has permission to access the variable, -
Instance profile credentials delivered through the Amazon EC2 metadata service
And the region from your AWS CLI profile will be used.
Next steps
Packaging
Packaging your application is as simple as ./mvnw clean package.
It can then be run with java -jar target/quarkus-app/quarkus-run.jar.
With GraalVM installed, you can also create a native executable binary: ./mvnw clean package -Dnative.
Depending on your system, that will take some time.
Going asynchronous
Thanks to the AWS SDK v2.x used by the Quarkus extension, you can use the asynchronous programming model out of the box.
Create a org.acme.cloudwatchlogs.QuarkusCloudWatchAsyncResource REST resource that will be similar to our QuarkusCloudWatchSyncResource but using an asynchronous programming model.
package org.acme.cloudwatchlogs;
import io.quarkus.logging.Log;
import io.smallrye.mutiny.Multi;
import io.smallrye.mutiny.Uni;
import jakarta.inject.Inject;
import jakarta.ws.rs.*;
import jakarta.ws.rs.core.MediaType;
import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsAsyncClient;
import software.amazon.awssdk.services.cloudwatchlogs.model.*;
import software.amazon.awssdk.services.cloudwatchlogs.paginators.GetLogEventsPublisher;
import java.time.Duration;
import java.util.function.Supplier;
@Path("/async")
public class QuarkusCloudWatchLogsAsyncLogsResource extends QuarkusCloudWatchLogsResource {
@Inject
CloudWatchLogsAsyncClient client;
@GET
@Produces(MediaType.TEXT_PLAIN)
public Uni<String> listLogEventsOfStream(@QueryParam("groupName") String groupName,
@QueryParam("streamName") String streamName) {
return Multi.createFrom().<OutputLogEvent>emitter((emitter) -> {
Log.info("List Logs for " + groupName + " - " + streamName);
GetLogEventsPublisher paginator = client
.getLogEventsPaginator(
generateGetLogEvents(groupName, streamName)
);
paginator.doAfterOnComplete(emitter::complete)
.doAfterOnError(emitter::fail)
.subscribe(response -> response.events()
.forEach(emitter::emit));
}).map(OutputLogEvent::message)
.collect().asList()
.map(value -> String.join(", ", value));
}
private static class LogGroupNotFoundYet extends Throwable {
}
@POST
@Produces(MediaType.TEXT_PLAIN)
public Uni<String> createLogStream(@FormParam("groupName") String groupName,
@FormParam("streamName") String streamName) {
Log.info("Create Log Stream for " + groupName + " - " + streamName);
final Supplier<Uni<CreateLogGroupResponse>> createLogGroupRequest = () ->
Uni.createFrom().completionStage(
client.createLogGroup(generateCreateLogGroupRequest(groupName))
);
final Supplier<Uni<CreateLogStreamResponse>> createLogStreamRequest = () -> Uni.createFrom().completionStage(
client.createLogStream(generateCreateLogStreamRequest(groupName, streamName))
);
final Uni<Void> ignore = Uni.createFrom().voidItem();
final Supplier<Uni<DescribeLogGroupsResponse>> describeLogGroupsRequest = () -> Uni.createFrom().completionStage(
client.describeLogGroups(generateDescribeLogGroupRequest(groupName))
);
final Supplier<Uni<DescribeLogGroupsResponse>> awaitForGroupToBeAvailable = () -> describeLogGroupsRequest.get()
.flatMap(response -> {
boolean logGroupCreated = response.logGroups().stream()
.anyMatch(logGroup -> logGroup.logGroupName().equals(groupName));
if (logGroupCreated) {
return Uni.createFrom().item(response);
} else {
return Uni.createFrom().failure(new LogGroupNotFoundYet());
}
}
).onFailure(LogGroupNotFoundYet.class).retry()
.withBackOff(Duration.ofMillis(100))
.indefinitely();
Uni<Void> createLogGroupIfNotExists = describeLogGroupsRequest.get().flatMap(
describeLogGroupsResponse -> {
if (describeLogGroupsResponse.logGroups().isEmpty()) {
return createLogGroupRequest.get().flatMap(createLogGroupResponse -> ignore);
} else {
return ignore;
}
}
);
return createLogGroupIfNotExists
.onFailure(ResourceAlreadyExistsException.class)
.recoverWithUni(ignore)
.flatMap(ignored -> awaitForGroupToBeAvailable.get())
.flatMap(ignored -> createLogStreamRequest.get())
.map(response -> "OK");
}
@PUT
@Produces(MediaType.TEXT_PLAIN)
public Uni<String> putLogEventsForStream(@FormParam("groupName") String groupName,
@FormParam("streamName") String streamName, @FormParam("message") String message) {
Log.info("Put Log Event for " + groupName + " - " + streamName);
return Uni.createFrom().completionStage(
client.putLogEvents(generatePutLogEventRequest(groupName, streamName, message))
).map(response -> "OK");
}
}Note that the CloudWatchAsyncClient behaves just like the CloudWatchClient, but returns CompletionStage objects which we use to create Uni/Multi instances, and then transform the emitted item.
To enable the asynchronous client, we also need to add the Netty HTTP client dependency to the pom.xml:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>netty-nio-client</artifactId>
</dependency>If you want to use the AWS CRT-based HTTP client instead, configure it as follows:
quarkus.cloudwatchlogs.async-client.type=aws-crtAnd add the following dependency to the application pom.xml:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>aws-crt-client</artifactId>
</dependency>Configuration Reference
Configuration property fixed at build time - All other configuration properties are overridable at runtime
Type |
Default |
|
|---|---|---|
List of execution interceptors that will have access to read and modify the request and response objects as they are processed by the AWS SDK. The list should consists of class names which implements Environment variable: |
list of string |
|
OpenTelemetry AWS SDK instrumentation will be enabled if the OpenTelemetry extension is present and this value is true. Environment variable: |
boolean |
|
Type of the sync HTTP client implementation Environment variable: |
|
|
Type of the async HTTP client implementation Environment variable: |
|
|
If a local AWS stack should be used. (default to true) If this is true and endpoint-override is not configured then a local AWS stack will be started and will be used instead of the given configuration. For all services but Cognito, the local AWS stack will be provided by LocalStack. Otherwise, it will be provided by Moto Environment variable: |
boolean |
|
Indicates if the LocalStack container managed by Dev Services is shared. When shared, Quarkus looks for running containers using label-based service discovery. If a matching container is found, it is used, and so a second one is not started. Otherwise, Dev Services starts a new container. The discovery uses the Sharing is not supported for the Cognito extension. Environment variable: |
boolean |
|
The value of the This property is used when you need multiple shared LocalStack instances. Environment variable: |
string |
|
Generic properties that are pass for additional container configuration. Environment variable: |
|
|
Type |
Default |
|
The endpoint URI with which the SDK should communicate. If not specified, an appropriate endpoint to be used for the given service and region. Environment variable: |
||
The amount of time to allow the client to complete the execution of an API call. This timeout covers the entire client execution except for marshalling. This includes request handler execution, all HTTP requests including retries, unmarshalling, etc. This value should always be positive, if present. Environment variable: |
||
The amount of time to wait for the HTTP request to complete before giving up and timing out. This value should always be positive, if present. Environment variable: |
||
Whether the Quarkus thread pool should be used for scheduling tasks such as async retry attempts and timeout task. When disabled, the default sdk behavior is to create a dedicated thread pool for each client, resulting in competition for CPU resources among these thread pools. Environment variable: |
boolean |
|
Type |
Default |
|
An Amazon Web Services region that hosts the given service. It overrides region provider chain with static value of region with which the service client should communicate. If not set, region is retrieved via the default providers chain in the following order:
See Environment variable: |
Region |
|
Configure the credentials provider that should be used to authenticate with AWS. Available values:
Environment variable: |
|
|
Type |
Default |
|
Whether this provider should fetch credentials asynchronously in the background. If this is Environment variable: |
boolean |
|
Whether the provider should reuse the last successful credentials provider in the chain. Reusing the last successful credentials provider will typically return credentials faster than searching through the chain. Environment variable: |
boolean |
|
Type |
Default |
|
AWS Access key id Environment variable: |
string |
|
AWS Secret access key Environment variable: |
string |
|
AWS Session token Environment variable: |
string |
|
Type |
Default |
|
The name of the profile that should be used by this credentials provider. If not specified, the value in Environment variable: |
string |
|
Type |
Default |
|
Whether the provider should fetch credentials asynchronously in the background. If this is true, threads are less likely to block when credentials are loaded, but additional resources are used to maintain the provider. Environment variable: |
boolean |
|
The amount of time between when the credentials expire and when the credentials should start to be refreshed. This allows the credentials to be refreshed *before* they are reported to expire. Environment variable: |
|
|
The maximum size of the output that can be returned by the external process before an exception is raised. Environment variable: |
|
|
The command that should be executed to retrieve credentials. Environment variable: |
string |
|
Type |
Default |
|
The name of custom AwsCredentialsProvider bean. Environment variable: |
string |
|
Type |
Default |
|
The maximum amount of time to establish a connection before timing out. Environment variable: |
|
|
The amount of time to wait for data to be transferred over an established, open connection before the connection is timed out. Environment variable: |
|
|
TLS key managers provider type. Available providers:
Environment variable: |
|
|
Path to the key store. Environment variable: |
path |
|
Key store type. See the KeyStore section in the https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html#KeyStore[Java Cryptography Architecture Standard Algorithm Name Documentation] for information about standard keystore types. Environment variable: |
string |
|
Key store password Environment variable: |
string |
|
TLS trust managers provider type. Available providers:
Environment variable: |
|
|
Path to the key store. Environment variable: |
path |
|
Key store type. See the KeyStore section in the https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html#KeyStore[Java Cryptography Architecture Standard Algorithm Name Documentation] for information about standard keystore types. Environment variable: |
string |
|
Key store password Environment variable: |
string |
|
Type |
Default |
|
The amount of time to wait when acquiring a connection from the pool before giving up and timing out. Environment variable: |
|
|
The maximum amount of time that a connection should be allowed to remain open while idle. Environment variable: |
|
|
The maximum amount of time that a connection should be allowed to remain open, regardless of usage frequency. Environment variable: |
||
The maximum number of connections allowed in the connection pool. Each built HTTP client has its own private connection pool. Environment variable: |
int |
|
Whether the client should send an HTTP expect-continue handshake before each request. Environment variable: |
boolean |
|
Whether the idle connections in the connection pool should be closed asynchronously. When enabled, connections left idling for longer than Environment variable: |
boolean |
|
Configure whether to enable or disable TCP KeepAlive. Environment variable: |
boolean |
|
Enable HTTP proxy Environment variable: |
boolean |
|
The endpoint of the proxy server that the SDK should connect through. Currently, the endpoint is limited to a host and port. Any other URI components will result in an exception being raised. Environment variable: |
||
The username to use when connecting through a proxy. Environment variable: |
string |
|
The password to use when connecting through a proxy. Environment variable: |
string |
|
For NTLM proxies - the Windows domain name to use when authenticating with the proxy. Environment variable: |
string |
|
For NTLM proxies - the Windows workstation name to use when authenticating with the proxy. Environment variable: |
string |
|
Whether to attempt to authenticate preemptively against the proxy server using basic authentication. Environment variable: |
boolean |
|
The hosts that the client is allowed to access without going through the proxy. Environment variable: |
list of string |
|
Type |
Default |
|
The maximum amount of time that a connection should be allowed to remain open while idle. Environment variable: |
|
|
The maximum number of allowed concurrent requests. Environment variable: |
int |
|
Enable HTTP proxy Environment variable: |
boolean |
|
The endpoint of the proxy server that the SDK should connect through. Currently, the endpoint is limited to a host and port. Any other URI components will result in an exception being raised. Environment variable: |
||
The username to use when connecting through a proxy. Environment variable: |
string |
|
The password to use when connecting through a proxy. Environment variable: |
string |
|
Type |
Default |
|
The maximum number of allowed concurrent requests. For HTTP/1.1 this is the same as max connections. For HTTP/2 the number of connections that will be used depends on the max streams allowed per connection. Environment variable: |
int |
|
The maximum number of pending acquires allowed. Once this exceeds, acquire tries will be failed. Environment variable: |
int |
|
The amount of time to wait for a read on a socket before an exception is thrown. Specify Environment variable: |
|
|
The amount of time to wait for a write on a socket before an exception is thrown. Specify Environment variable: |
|
|
The amount of time to wait when initially establishing a connection before giving up and timing out. Environment variable: |
|
|
The amount of time to wait when acquiring a connection from the pool before giving up and timing out. Environment variable: |
|
|
The maximum amount of time that a connection should be allowed to remain open, regardless of usage frequency. Environment variable: |
||
The maximum amount of time that a connection should be allowed to remain open while idle. Currently has no effect if Environment variable: |
|
|
Whether the idle connections in the connection pool should be closed. When enabled, connections left idling for longer than Environment variable: |
boolean |
|
Configure whether to enable or disable TCP KeepAlive. Environment variable: |
boolean |
|
The HTTP protocol to use. Environment variable: |
|
|
The SSL Provider to be used in the Netty client. Default is Environment variable: |
|
|
The maximum number of concurrent streams for an HTTP/2 connection. This setting is only respected when the HTTP/2 protocol is used. Environment variable: |
long |
|
The initial window size for an HTTP/2 stream. This setting is only respected when the HTTP/2 protocol is used. Environment variable: |
int |
|
Sets the period that the Netty client will send This setting is only respected when the HTTP/2 protocol is used. Environment variable: |
|
|
Enable HTTP proxy. Environment variable: |
boolean |
|
The endpoint of the proxy server that the SDK should connect through. Currently, the endpoint is limited to a host and port. Any other URI components will result in an exception being raised. Environment variable: |
||
The hosts that the client is allowed to access without going through the proxy. Environment variable: |
list of string |
|
TLS key managers provider type. Available providers:
Environment variable: |
|
|
Path to the key store. Environment variable: |
path |
|
Key store type. See the KeyStore section in the https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html#KeyStore[Java Cryptography Architecture Standard Algorithm Name Documentation] for information about standard keystore types. Environment variable: |
string |
|
Key store password Environment variable: |
string |
|
TLS trust managers provider type. Available providers:
Environment variable: |
|
|
Path to the key store. Environment variable: |
path |
|
Key store type. See the KeyStore section in the https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html#KeyStore[Java Cryptography Architecture Standard Algorithm Name Documentation] for information about standard keystore types. Environment variable: |
string |
|
Key store password Environment variable: |
string |
|
Enable the custom configuration of the Netty event loop group. Environment variable: |
boolean |
|
Number of threads to use for the event loop group. If not set, the default Netty thread count is used (which is double the number of available processors unless the Environment variable: |
int |
|
The thread name prefix for threads created by this thread factory used by event loop group. The prefix will be appended with a number unique to the thread factory and a number unique to the thread. If not specified it defaults to Environment variable: |
string |
|
Whether the default thread pool should be used to complete the futures returned from the HTTP client request. When disabled, futures will be completed on the Netty event loop thread. Environment variable: |
boolean |
|
|
About the Duration format
To write duration values, use the standard You can also use a simplified format, starting with a number:
In other cases, the simplified format is translated to the
|
|
About the MemorySize format
A size configuration option recognises string in this format (shown as a regular expression): |