Private/AwsModuleChecks.ps1

<#
.NOTES
    Author: Robert D. Biddle
    https://github.com/RobBiddle
    https://github.com/RobBiddle/PackerBaseAMI
    PackerBaseAMI Copyright (C) 2017 Robert D. Biddle
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    This is free software, and you are welcome to redistribute it
    under certain conditions; for details type `"help New-PackerBaseAMI -full`".
    This program is free software: you can redistribute it and/or modify
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    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with this program. If not, see <http://www.gnu.org/licenses/>.
    The GNU General Public License does not permit incorporating your program
    into proprietary programs. If your program is a subroutine library, you
    may consider it more useful to permit linking proprietary applications with
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#>

function Confirm-AwsModulesAreInstalled {
    $legacyAwsModule = 'AWSPowerShell'
    $requiredAwsModules = 'AWS.Tools.Common', 'AWS.Tools.EC2', 'AWS.Tools.SecurityToken', 'AWS.Tools.SimpleSystemsManagement'
    $StartingErrorActionPreference = $ErrorActionPreference
    $ErrorActionPreference = "silentlycontinue"
    $AwsModulesFound = $true
    $legacyAwsModuleFound = $false

    # Check for the legacy AWSPowerShell module
    if (Get-Module -ListAvailable -Name $legacyAwsModule) {
        $legacyAwsModuleFound = $true
        Write-Warning "The legacy AWSPowerShell module is installed. It is recommended to use the AWS.Tools modules instead."
    }

    # Check for the required AWS.Tools modules
    if (-not $legacyAwsModuleFound) {
        foreach ($module in $requiredAwsModules) {
            if (-not (Get-Module -ListAvailable -Name $module)) {
                $AwsModulesFound = $false
                Throw "Module $module not found. Please install the required AWS.Tools modules from the PowerShell Gallery"
            }
        }
    }

    $ErrorActionPreference = $StartingErrorActionPreference
    Return $AwsModulesFound
}