Initial work

Author: Caleb Brose

SAMPLE-action.ps1

@@ -0,0 +1,256 @@
+#!/usr/bin/env pwsh
+
+[cmdletbinding()]
+param()
+
+if (-not (Get-Module -ListAvailable GitHubActions)) {
+    Install-Module GitHubActions -Force
+}
+
+Import-Module GitHubActions
+
+## Pull in some inputs
+$repositoryUrl  = Get-ActionInput repositoryUrl -Required
+$defaultBranch  = Get-ActionInput defaultBranch
+$rootDocsFolder = Get-ActionInput root
+$convertRootReadmeToHomePage = Get-ActionInput convertRootReadmeToHomePage
+$useHeaderForWikiName = Get-ActionInput useHeaderForWikiName
+
+$wikiRepoName = ($repositoryUrl -split "/")[-1] + ".wiki"
+$wikiRepoUrl = "$repositoryUrl.wiki.git"
+
+if (-not $defaultBranch) {
+    $defaultBranch = git branch --show-current
+}
+
+if (-not $rootDocsFolder)
+{
+    $rootDocsFolder = "."
+    $rootDocsFolderDirs = @()
+}
+else
+{
+    $rootDocsFolderDirs = $rootDocsFolder -split "/"
+}
+
+$filenameToWikiNameMap = @{}
+$wikiNameToFileNameMap = @{}
+
+Function ProcessSourceDirectory()
+{
+    [cmdletbinding()]
+    param([string[]]$directories=@())
+
+    foreach ($file in Get-ChildItem "*.md")
+    {
+        ProcessSourceFile $file $directories
+    }
+
+    foreach ($dir in Get-ChildItem -Directory)
+    {
+        Push-Location $dir.Name
+
+        ProcessSourceDirectory ($directories + @($dir.Name))
+
+        Pop-Location
+    }
+}
+
+Function ProcessSourceFile()
+{
+    [cmdletbinding()]
+    param($file, [string[]]$directories)
+
+    Write-Verbose "Processing file $($file.FullName)"
+
+    $outputFileName = ($directories + $file.Name) -join "__"
+
+    $content = Get-Content -Path $file.FullName
+    $content = UpdateFileLinks $file.Name $directories $content
+
+    $override = GetOutputFileNameFromFile $content
+
+    if ($convertRootReadmeToHomePage -and ($directories.Count -eq 0) -and ($file.Name -eq "readme.md"))
+    {
+        $outputFileName = "Home.md"
+    }
+    elseif ($override)
+    {
+        Write-Verbose "Using overridden file name $($override.FileName)"
+
+        if ($wikiNameToFileNameMap[$override.FileName])
+        {
+            throw "Overridden file name $($override.FileName) is already in use by $($wikiNameToFileNameMap[$override.FileName])"
+        }
+        $wikiNameToFileNameMap[$override.FileName] = $outputFileName
+
+        $filenameToWikiNameMap[$outputFileName] = $override.FileName
+        $outputFileName = $override.FileName        
+
+        $content = $override.NewContent
+    }
+
+    $outputPath = $wikiRepoPath + "/" + $outputFileName
+
+    $content | Set-Content -Path $outputPath
+}
+
+Function GetOutputFileNameFromFile()
+{
+    [cmdletbinding()]
+    param($content)
+
+    if ($useHeaderForWikiName)
+    {
+        $firstLine = $content | Select-Object -First 1
+        $headerMatch = [regex]::match($firstLine, "^#\s+(.*)$")
+        if ($headerMatch.Success)
+        {
+            $filename = $headerMatch.Groups[1].Value
+            $filename = $filename -replace " ", "-"
+            $filename = $filename -replace "[^A-Za-z0-9\s.(){}_!?-]", ""
+
+            return @{
+                FileName = "$filename.md";
+                NewContent = $content[1..$content.Count];
+            }
+        }
+    }
+}
+
+Function UpdateFileLinks()
+{
+    [cmdletbinding()]
+    param($filename, [string[]]$directories, $content)
+
+    $evaluator = { 
+        [cmdletbinding()]
+        param($match)
+
+        $text = $match.Groups[1].Value
+        $link = $match.Groups[2].Value
+
+        if ($link -like "http*")
+        {
+            # Absolute link, no change
+            Write-Verbose "Link $link is already absolute, nothing to do"
+            return "[$text]($link)"
+        }
+        
+        $upDirs = 0
+        $path = @()
+
+        $link -split "/" | % {
+            if ($_ -eq "..") 
+            {
+                $upDirs += 1
+            }
+            else
+            {
+                $path += @($_)
+            }
+        }
+
+        if (($upDirs -le $directories.Count) -and ($link -like "*.md"))
+        {
+            # Link to another doc which should now point to a wiki file
+
+            $relativeWikiPath = @($directories | Select-Object -First ($directories.Count - $upDirs)) + @($path)
+            $wikiFileName = ($relativeWikiPath -join "__") -replace ".md$", ""
+    
+            Write-Verbose "Link $link updated to $wikiFileName"
+            return "[$text]($wikiFileName)"
+        }
+
+        # Outside the root directory or not a doc, convert to absolute Url
+        $extraUpDirs = $upDirs - $directories.Count
+        
+        if ($extraUpDirs -gt $rootDocsFolderDirs.Count)
+        {
+            throw "Relative link $link in $filename does not exist"
+        }
+
+        $relativePathFromRoot = ($rootDocsFolderDirs | Select-Object -First ($rootDocsFolderDirs.Count - $extraUpDirs)) -join "/"
+        if ($relativePathFromRoot) { $relativePathFromRoot += "/" }
+
+        $absoluteLink = $repositoryUrl + "/blob/$defaultBranch/" + $relativePathFromRoot + ($path -join "/")
+
+        if ($link -like "*.md")
+        {
+            Write-Verbose "Link $link is outside the docs root, updating to absolute link $absoluteLink"
+        }
+        else
+        {
+            Write-Verbose "Link $link is not a doc, updating to absolute link $absoluteLink"
+        }
+
+        return "[$text]($absoluteLink)"
+    }
+
+    # TODO - handle nested brackets
+    # Matches `[text](link)`
+    $linkRegex = [regex]"\[([^\]]+)\]\(([^\)]+)\)"
+
+    $content | % { $linkRegex.Replace($_, $evaluator) }
+}
+
+Function ProcessWikiDirectory()
+{
+    [cmdletbinding()]
+    param([string[]]$directories=@())
+
+    foreach ($file in Get-ChildItem "*.md")
+    {
+        ProcessWikiFile $file $directories
+    }
+
+    foreach ($dir in Get-ChildItem -Directory)
+    {
+        Push-Location $dir.Name
+
+        ProcessWikiDirectory ($directories + @($dir.Name))
+
+        Pop-Location
+    }
+}
+
+Function ProcessWikiFile()
+{
+    [cmdletbinding()]
+    param($file, [string[]]$directories)
+
+    Write-Verbose "Processing file $($file.Name)"
+
+    $content = Get-Content $file
+    $filenameToWikiNameMap.Keys | % {
+        $originalLink = $_ -replace ".md$", ""
+        $newLink = $filenameToWikiNameMap[$_] -replace ".md$", ""
+
+        $content = $content -replace $originalLink, $newLink
+    }
+
+    Set-Content -Path $file.FullName -Value $content -Force
+}
+
+Push-Location ..
+Write-Information "Cloning wiki repo..."
+git clone $wikiRepoUrl
+$wikiRepoPath = $pwd.Path + "/" + $wikiRepoName
+cd $wikiRepoName
+git rm -rf * | Out-Null
+Pop-Location
+
+Push-Location $rootDocsFolder
+Write-Information "Processing source directory..."
+ProcessSourceDirectory
+Pop-Location
+
+Push-Location ..\$wikiRepoName
+Write-Information "Post-processing wiki files..."
+ProcessWikiDirectory
+
+Write-Information "Pushing wiki"
+git add .
+git commit -am "Sync Files"
+git push
+Pop-Location

SAMPLE-action.yml

@@ -0,0 +1,39 @@
+name: github-docs-to-wiki
+author: cmbrose
+description: Converts markdown content in a repository into a wiki.
+
+inputs:
+
+  repositoryUrl:
+    description: The url of the repository being operated on
+    required: true
+
+  defaultBranch:
+    description: The default branch name (master, main, etc)
+    required: false
+    default: The value returned by `git branch --show-current`
+
+  rootDocsFolder:
+    description: A directory within the repository where the docs are located
+    required: false
+    default: The repository's root
+
+  convertRootReadmeToHomePage:
+    description: If true, renames the README.md file to Home.md in the wiki (the wiki homepage)
+    required: false
+    default: false
+
+  useHeaderForWikiName:
+    description: If true, names wiki pages according to the top header of the source file (using `#`)
+    required: false
+    default: false
+
+outputs:
+
+branding:
+  color: purple
+  icon: terminal
+
+runs:
+  using: node12
+  main: _init/index.js