StartEnvironmentDeployment.ps1

$token = '<API_Token>'

$headers = @{
  "Authorization" = "Bearer $token"
  "Content-type" = "application/json"
}

#if you do not know build version and want to use latest:
#$buildVersion = (Invoke-RestMethod -Uri "https://ci.appveyor.com/api/projects/<Your_account>/<Your_project_slug>" -Headers $headers  -Method GET).build.version

#if you need latest build version for specific branch:
#$buildVersion = (Invoke-RestMethod -Uri "https://ci.appveyor.com/api/projects/<Your_account>/<Your_project_slug>/branch/<branch_name>" -Headers $headers  -Method GET).build.version

$body = @{
    environmentName="<Your_environment>"
    accountName="<Your_account>"
    projectSlug="<Your_project_slug>"
    # $env:APPVEYOR_BUILD_VERSION can be used when calling from build job 
    # or $buildVersion if you are calling separately (see how we get it above commented)
    buildVersion="<build_version_to_deploy>"
    environmentVariables = @{
      my_var=$myVar 
    } 
}

$body = $body | ConvertTo-Json

Invoke-RestMethod -Uri 'https://ci.appveyor.com/api/deployments' -Headers $headers  -Body $body -Method POST