Terraecs is a simple cli tool to run a once-off ECS/Fargate task that relies on a terraformed infrastructure.
Preview release, please do not use for anything important!
- I want to run a command (be it ror-rake, laravel-artisan, etc.) in a Fargate environment
- I use terraform for IaC, and do not want to deviate from that
- I also do not want to think about infrastructure when running a command, as it should be already setup via terraform
- These once-off tasks are dirty, I want to have direct feedback on how it went (logs + exit status)
$ pip install terraecs
You will need to create a Fargate task module to create a task-definition and any other supporting resources (networking/cloudwatchlogs). At a minimum the module will have to output the following:
output "cluster_id" { value = "${var.cluster_id}" } output "subnets" { value = "${var.subnets}" } output "security_group_id" { value = "${aws_security_group.main.id}" } output "task_definition_arn" { value = "${aws_ecs_task_definition.main.arn}" }
Terraform 0.12 and later intentionally track only root module outputs in the state. To expose module outputs for external consumption, you must export them from the root module using an output block, which as of 0.12 can now be done for a single module all in one output:
output "custom_ecs_task" { value = module.custom_ecs_task }
Once you have applied your terraform config, pull the output into a json:
$ terraform output -json custom_ecs_task > output.jsonNow you can use terraecs to run any command based off the above task-definition:
$ terraecs -f output.json run "command" "arg1" "arg2"
The output can look something like this:
❯ AWS_PROFILE=staging terraecs -f output.json run artisan --help 2019年04月10日 08:14:01,884 botocore.credentials [INFO] Found credentials in shared credentials file: ~/.aws/credentials 2019年04月10日 08:14:03,893 root [INFO] launched task: arn:aws:ecs:eu-west-1:1111111111111:task/staging-main/4544cfd6f10e4ff0b16458666362cbd9 2019年04月10日 08:14:04,069 root [INFO] PROVISIONING 2019年04月10日 08:14:25,461 root [INFO] PENDING 2019年04月10日 08:15:51,642 root [INFO] DEPROVISIONING 2019年04月10日 08:16:13,632 root [INFO] STOPPED Description: Lists commands Usage: list [options] [--] [<namespace>] Arguments: namespace The namespace name Options: --raw To output raw command list --format=FORMAT The output format (txt, xml, json, or md) [default: "txt"] Help: The list command lists all commands: php artisan list You can also display the commands for a specific namespace: php artisan list test You can also output the information in other formats by using the --format option: php artisan list --format=xml It's also possible to get raw list of commands (useful for embedding command runner): php artisan list --raw