Vague error message if zip command is missing in AWSLambdaPSCore

Description

When setting up AWSLambdaPSCore on a fresh EC2 instance running Ubuntu Server 20.04 LTS, some dependencies for the AWSLambdaPSCore module are not pre-installed. If you attempt to publish a PowerShell-based AWS Lambda function, you receive a very bizarre error message.

• zip command is not installed by default

Expected Behavior

The Publish-AWSPowerShellLambda command should run dependency checks early on, before running the dotnet restore command, so that any missing utilities can be installed, and DOTNET_ROOT is set correctly. Any missing dependencies should be listed out, along with remediation commands, to provide a pleasant user experience for this command.

I’ve also come across an issue where libhostfxr.so could not be found. I think that’s somehow related to DOTNET_ROOT, but I’m not entirely sure, as I can’t seem to intentionally reproduce it. I think it had something to do with having .NET Core 5.0 installed, but not 3.1.

Here’s a list of dependency checks that I’m currently aware of, which should be executed each time an invocation of Publish-AWSPowerShellLambda is made:

• .NET Core SDK installed
• DOTNET_ROOT set correctly (if required)
• libhostfxr.so can be located
• zip command is installed

There may be other dependency checks that should be included as well, so please feel free to add them to this issue report.

Reproduction Steps

bash> sudo snap install powershell --classic
bash> pwsh
PS > Install-Module -Name AWSLambdaPSCore -Scope CurrentUser -Force
PS > Publish-AWSPowerShellLambda ..........

Zipping publish folder /tmp/generatetonsofdata.ps1/bin/Release/netcoreapp3.1/publish to /tmp/generatetonsofdata.ps1/bin/Release/netcoreapp3.1/generatetonsofdata.ps1.zip
Failed to find the "zip" utility program in path. This program is required to maintain Linux file permissions in the zip archive.
Exception: /home/ubuntu/.local/share/powershell/Modules/AWSLambdaPSCore/2.0.0.0/Private/_DeploymentFunctions.ps1:203
Line |
 203 |              throw $msg
     |              ~~~~~~~~~~
     | Error publishing PowerShell Lambda Function: 255 CALLSTACK: Command                     Arguments -------                     ---------
     | _deployProject              {ProfileName=, PowerShellFunctionHandler=, Region=, EnvironmentVariables=, Tags=, PublishNewVersion=, DisableInteractive=,
     | FunctionRole=arn:aws:iam::665453315… Publish-AWSPowerShellLambda {Name=generatetonsofdata, ScriptPath=./generatetonsofdata.ps1/generatetonsofdata.ps1.ps1,
     | IAMRoleArn=arn:aws:iam::665453315198:role/lambdaworkspacescleanup}    <ScriptBlock>               {}

Environment

Name                           Value
----                           -----
PSVersion                      7.1.2
PSEdition                      Core
GitCommitId                    7.1.2
OS                             Linux 5.4.0-1038-aws #40-Ubuntu SMP Fri Feb 5 23:50:40 UTC 2021
Platform                       Unix
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Resolution

• 👋 I can/would-like-to implement a fix for this problem myself

---

This is a 🐛 bug-report

[ashishdhingra]

@pcgeek86 Thanks for your response. I will convert this to feature-request and have developer look at it.

[github-actions[bot]]

We have noticed this issue has not received attention in 1 year. We will close this issue for now. If you think this is in error, please feel free to comment and reopen the issue.