aws-ecs-tools

A collection of Ruby scripts that make it easier to work with ECS from the command line.

param_tool.rb

A tool to sync up AWS Systems Manager Parameter Store with a local YAML file.

WIP; TODO a prettier name.

Usage: param_tool.rb [options] (down|up)
    -f, --file=FILE                  File with params
    -p, --prefix=PREFIX              Param prefix
    -k, --key=KEY                    Encryption key for writing secure params (no effect on reading)
    -d, --decrypt                    Output decrypted params
    -y, --yes                        Apply changes without asking for confirmation (DANGER)

Download params

param_tool.rb --prefix /staging/myapp down >params.yml

Secure (encrypted) param values are replaced with SECURE - NOT decrypted.
To decrypt, use -d key.
Secure param keys are suffixed with '!'
Params are converted into a tree, using slashes as nesting separators.

Upload params

# see planned changes, confirm, apply:
param_tool.rb --prefix /staging/myapp --file params.yml up

Planned changes:
create /staging/myapp/host = "app.com"
delete /staging/myapp/deprecated
update /staging/myapp/port = "80"
Apply? (anything but "yes" will abort): yes
writing parameter /staging/myapp/host...done
deleting parameter /staging/myapp/deprecated...done
writing parameter /staging/myapp/port...done
All done!

# non-interactive mode (and you can pass params to standard input)
my_param_generating_script.sh | param_tool.rb --prefix /staging/myapp --yes up

# specify a key to do the encryption:
param_tool.rb --key alias/mailtrap-parameter-store --prefix /staging/myapp --file params.yml up

params that are not changed will not be updated
secure params that have a value of SECURE are NOT updated
secure params that have any other value ARE updated - then make sure to provide the proper key
to make a param secure, add a ! suffix to the key name - note that the '!' character itself will be stripped from the key name in Parameter Store
params with a value of DELETE are deleted from parameter store

Workflow concept

create a YAML file with the params you need; you can reuse the same file for a file-based Global backend.
upload it to staging
upload it to prod
download params from staging, update, and send to prod
commit param set as reference (make sure that sensitive params are secured, and thus not committed)

Sample params.yml

---
aws:
  bucket: my-bucket
braintree:
  environment: sandbox
  merchant_id!: SECURE
  private_key!: SECURE
  public_key!: SECURE
heroku:
  addon_manifest: |-
    {
     "hey!": "you can do multiline values too",
     "useful": "for SSH keys"
    }

ecs_run.rb

Run shell script or Ruby code on an ECS service

Usage: ecs_run.rb [options] [command or STDIN]
    -c, --cluster=CLUSTER            Cluster name
    -s, --service=SERVICE            Service name
    -w, --watch                      Watch output
    -r, --ruby                       Run input as Ruby code with Rails runner (instead of shell command)
    -R, --region                     AWS region to use

Note that the command is non-interactive - you provide the code and you watch it execute.

Specify target

Cluster and service are required params. Besides them, you'll need to set the region through environment variables.

The command retrieves the task definition, subnet, and security group from the service automatically.

Providing input

There are three ways to provide input:

as a final argument to the command - make sure to quote it properly
```
ecs_run.rb -c app -s app 'rake -T'
```
from a file
```
ecs_run.rb -c app -s app <script.sh
```

type it in

ecs_run.rb -c app -s app
Type your command then press Ctrl+D
rake -T
[Ctrl+D]

Note that in all cases you're providing literal code to be evaluated on the ECS service; you can't send files; the rest of the environment is defined by the service.

Watching output

Normally after you start the task you get an AWS Console link to monitor the task online, and that's it.

But if you specify the --watch option, you will see the task status changes and the output logged to the terminal. You will also know when the task has finished.

Running Ruby code

Besides running shell code, you can also run Ruby code with the Rails runner (only available if bundle and a Rails app are present in your service's docker image.)

ecs_run.rb -c app -s app --ruby 'p User.first'

This way you get Rails log output, but note that, unlike a Rails console, you don't see command evaluation results by default - you need to print it explicitly.

Example

$ ruby ecs_run.rb --cluster myapp --service myapp --watch --ruby
Type your command then press Ctrl+D
Note - Ruby evaluation result is NOT automatically printed, use `p`
User.where("email LIKE '%@myapp.com'").update_all(role: 'admin')
^D
Task started. See it online at https://us-east-1.console.aws.amazon.com/ecs/home?region=us-east-1#/clusters/mailtrap/tasks/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/details
Watching task output. Note - Ctrl+C will stop watching, but will NOT stop the task!
[2020-07-25 08:42:01 +0300] Task status changed to PROVISIONING
[2020-07-25 08:42:23 +0300] Task status changed to PENDING
[2020-07-25 08:43:18 +0300] Task status changed to RUNNING
[2020-07-25 08:43:42 +0300] I, [2020-07-25T05:43:37.853603 #7]  INFO -- : Raven 3.0.0 ready to catch errors
[2020-07-25 08:44:01 +0300] Task status changed to DEPROVISIONING
[2020-07-25 08:44:14 +0300] Task status changed to STOPPED

ayarotsky/aws-ecs-tools