Elastic Load Balancing
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LocalStack Pro supports Elastic Load Balancing operations for both version 1 and 2.
Application load balancers also support request forwarding to IP address and Lambda targets.
IP Targets
This example illustrates a load balancer configured for an IP target.
Start an HTTP server which will serve as the target of our load balancer.
$ docker run --rm -itd -p 5678:80 ealen/echo-serverCreate the load balancer, target group and register the target, which is the above Docker container in this case.
$ subnet=$(awslocal ec2 describe-subnets --filters Name=availability-zone,Values=us-east-1f | jq -r '.Subnets[].SubnetId')
$ loadBalancer=$(awslocal elbv2 create-load-balancer --name example-lb --subnets $subnet \
| jq -r '.LoadBalancers[]|.LoadBalancerArn')
$ targetGroup=$(awslocal elbv2 create-target-group --name example-target-group --protocol HTTP --target-type ip \
| jq -r '.TargetGroups[].TargetGroupArn')
$ awslocal elbv2 register-targets --targets Id=127.0.0.1,Port=5678,AvailabilityZone=all --target-group-arn $targetGroupCreate a listener and a rule so that incoming requests are forwarded to the target.
$ listenerArn=$(awslocal elbv2 create-listener \
--default-actions '{"Type":"forward","TargetGroupArn":"'$targetGroup'","ForwardConfig":{"TargetGroups":[{"TargetGroupArn":"'$targetGroup'","Weight":11}]}}' \
--load-balancer-arn $loadBalancer | jq -r '.Listeners[]|.ListenerArn')
$ listenerRule=$(awslocal elbv2 create-rule \
--conditions Field=path-pattern,Values=/ \
--priority 1 \
--actions '{"Type":"forward","TargetGroupArn":"'$targetGroup'","ForwardConfig":{"TargetGroups":[{"TargetGroupArn":"'$targetGroup'","Weight":11}]}}' \
--listener-arn $listenerArn \
| jq -r '.Rules[].RuleArn')Finally, we issue an HTTP request to the DNSName parameter of CreateLoadBalancer operation, and Port parameter of CreateListener command.
In the above example, these parameters are filtered using jq.
$ curl example-lb.elb.localhost.localstack.cloud:4566
{"host":{"hostname":"..."},"http":{"method":"GET","baseUrl":"","originalUrl":"/","protocol":"http"},...}}Limitations
The Aplication Load Balancer currently supports only the forward and redirect action types.