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Mass Preview Init

mass preview init

Generate a preview enviroment configuration file


Initialize a Preview Environment Config File

The preview environment config file should be checked into your source repository. The preview.json file supports bash interpolation in the event you need to dynamically set values from your CI.


mass preview init $yourProjectSlug

mass preview init ecomm

mass preview init ecomm --output path/to/my/preview.json

Preview Environment Config Files

The preview.json file serves two purposes in your preview environment:

  1. describes which clouds and the authentication to use
  2. sets the input parameters for each of your packages
"credentials": {
// Using an AWS IAM Role
"massdriver/aws-iam-role": "00000000-0000-0000-0000-000000000000"
"packageParams": {
"database": {
"cpus": "1",
"memory": "over9000GB"
"my-api": {
"image": "evilcorp/api:$IMAGE_TAG"
mass preview init $projectSlug [flags]


  -h, --help            help for init
-o, --output string Output path for preview environment params file. This file supports bash interpolation and can be manually edited or programatically modified during CI. (default "./preview.json")