Public/Get-XKCDCache.ps1
|
Function Get-XKCDCache { <# .SYNOPSIS Returns the details of comics @ https://xkcd.com/ from the local cache. .DESCRIPTION The Get-XKCDCache cmdlet returns comic data straight from the local cache, without querying the XKCD API for each individual comic. This makes it a much faster way to retrieve the details of comics that have already been cached, and lets you use Where-Object, Sort-Object, Group-Object etc. to query the whole set of comics at once. Unlike Find-XKCD, this cmdlet does not create or refresh the cache itself. It only checks whether the cache exists and is up to date, and warns you to run Update-XKCDCache if it isn't. .EXAMPLE Get-XKCDCache Returns every comic in the local cache. .EXAMPLE Get-XKCDCache -Num 4,5,6 Returns comics 4, 5 and 6 from the local cache. .EXAMPLE 4,5,6 | Get-XKCDCache Returns comics 4, 5 and 6 from the local cache, specified via the pipeline. .EXAMPLE Get-XKCDCache | Where-Object year -eq 2010 Returns every comic published in 2010, by filtering the full local cache. .EXAMPLE Get-XKCDCache | Sort-Object -Property { $_.title.Length } -Descending | Select-Object -First 1 title Returns the comic with the longest title. .LINK https://xkcd.com/json.html #> [cmdletbinding()] Param( # Returns only the specified comic numbers from the cache. Accepts array and pipeline input. By default every # cached comic is returned. [Parameter(ValueFromPipeline, ValueFromPipelineByPropertyName, Position = 0)] [int[]] $Num, # Path to where comic data is cached. By default this is within the module path, unless a default has # been saved with Set-XKCDDefault -CachePath. [string] $CachePath = (Get-XKCDDefaultValue -Name 'CachePath' -Value (Join-Path $PSScriptRoot 'XKCD.json')) ) begin { if (Test-Path $CachePath) { $AllComics = Get-Content $CachePath | ConvertFrom-Json $LastComic = ($AllComics | Sort-Object num -Descending | Select-Object -First 1).num $Latest = (Invoke-RestMethod 'https://xkcd.com/info.0.json').num if ($Latest -gt $LastComic) { Write-Warning "The local cache is out of date (latest cached comic is #$LastComic, #$Latest is now available). Run Update-XKCDCache to refresh it." } } else { Write-Warning "No local cache was found at '$CachePath'. Run Update-XKCDCache to create one." $AllComics = @() } } process { if ($Num) { $AllComics | Where-Object { $_.num -in $Num } } else { $AllComics } } } |