Cache NuGet Packages with Cache Task in Azure DevOps YAML

build.yml

    - powershell: | # generates a hash of all packages.config and saves each on a single line on 'hash.txt'
        Get-FileHash -Algorithm MD5 -Path (Get-ChildItem packages.config -Recurse) >> hash.txt
        Write-Host "Hash File saved to $pwd\hash.txt"
      workingDirectory: src
      displayName: 'Calculate and save packages.config hash'
      
    - task: CacheBeta@0 # speed up builds by caching packages folder
      inputs:
        key: nuget|1|$(Agent.OS)|$(Build.SourcesDirectory)\src\hash.txt # hash map generated in previous step
        path: $(Build.SourcesDirectory)\src\packages
        cacheHitVar: 'nuget_cache_hit' # variable that can be checked to see if it was successful
      displayName: Cache nuget packages
      continueOnError: true