Server-side settings are configurable via configuration files. Default settings for all environments can be found in config/defaults.js.
Different environments may require different settings (e.g. rate at which you
want to make AWS API calls may be different on a laptop vs production
environment).
Settings can be overridden per environment by adding entries to a config file
with a name matching the TARGET_ENV environment variable.
E.g. if TARGET_ENV = test, the config/env/test.js file overrides will be
applied and override the settings in config/defaults.js.
Note: TARGET_ENV is kept distinct from NODE_ENV as the recommended Express
JS setting for NODE_ENV is production when running outside a development
context (see: https://expressjs.com/en/advanced/best-practice-performance.html#set-node_env-to-production)
Blank files are provided for the following configuration files:
TARGET_ENV |
Configuration File |
|---|---|
undefined |
config/env/dev.js (dev environment is assumed if TARGET_ENV not set) |
"dev" |
config/env/dev.js |
"test" |
config/env/test.js |
"prod" |
config/env/prod.js |
The following configuration options are available:
| Config Key | Description | Default |
|---|---|---|
port |
Server port to listen on | 3000 |
clusterStateCacheTtl |
Expiry time (in milliseconds) per cluster data entry in cluster state cache | 1800000 (30 mins) |
aws.configFile |
Configuration file containing AWS SDK configuration | ./aws_config.json |
aws.apiDelay |
Number of milliseconds to pause between AWS API calls to prevent API rate limiting | 100 |
aws.listInstancesPageSize |
Number of Instances to retrieve per listInstances ECS API call (max 100) |
100 |
aws.describeInstancesPageSize |
Number of Instances to retrieve per describeInstances ECS API call (max 100) |
100 |
aws.listTasksPageSize |
Number of Tasks to retrieve per listTasks ECS API call (max 100) |
100 |
aws.describeTasksPageSize |
Number of Tasks to retrieve per describeTasks ECS API call (max 100) |
100 |
aws.maxSimultaneousDescribeTasksCalls |
Number of describeTasks ECS API calls to make in quick succession before waiting for results |
2 |
aws.maxSimultaneousDescribeTaskDefinitionCalls |
Number of describeTaskDefinitions ECS API calls to make in quick succession before waiting for results |
1 |