Azure DevOps API: Get all files (source and target) of Pull Request - api

Question

I searched quite a bit, found several threads here (e.g. this, that, and more), but I could not find the answer to the following task:
Use the Azure DevOps API to retrieve the content changes (basically the file before and after) of all the files of a specific PR.
I can find a PR, can loop through changes, iterations, commits (in various combinations), but I have not been able to download both the first and the last version of each or the files (and there should be a way as I can view the before and after in a PR in DevOps).
Any hints where/how I can retrieve both versions of a file of a certain commit/change/iteration?
Many thanks in advance!
Cheers,
Udo

Answer 1

Thanks for all the hints. Looks like I managed to find a wat to pull it. Please feel free to correct my approach.
Here's the complete PowerShell file:
[CmdletBinding()]
param (
[int]
$pullRequestId,
[string]
$repoName
)
# --- your own values ---
$pat = 'your-personal access token for Azure DevOps'
$urlOrganization = 'your Azure DevOps organization'
$urlProject = 'your Azure DevOps project'
$basePath = "$($env:TEMP)/pullRequest/" # a location to store all the data
# --- your own values ---
if (!$repoName)
{
$userInput = Read-Host "Please enter the repository name"
if (!$userInput)
{
Write-Error "No repository name given."
exit
}
$repoName = $userInput
}
if (!$pullRequestId)
{
$userInput = Read-Host "Please enter the PullRequest ID for $($repoName)"
if (!$userInput)
{
Write-Error "No PullRequest ID given."
exit
}
$pullRequestId = $userInput
}
$prPath = "$($basePath)$($pullRequestId)"
$sourcePath = "$($basePath)$($pullRequestId)/before"
$targetPath = "$($basePath)$($pullRequestId)/after"
# --- helper methods ---
function CleanLocation([string]$toBeCreated)
{
RemoveLocation $toBeCreated
CreateLocation $toBeCreated
if (!(Test-Path $toBeCreated))
{
Write-Error "Path '$toBeCreated' could not be created"
}
}
function CreateLocation([string]$toBeCreated)
{
if (!(Test-Path $toBeCreated)) { New-Item -ErrorAction Ignore -ItemType directory -Path $toBeCreated > $null }
}
function RemoveLocation([string]$toBeDeleted)
{
if (Test-Path $toBeDeleted) { Remove-Item -Path $toBeDeleted -Recurse -Force }
}
function DeleteFile([string]$toBeDeleted)
{
if (Test-Path $toBeDeleted) { Remove-Item -Path $toBeDeleted -Force }
}
# --- helper methods ---
# --- Azure DevOps helper methods ---
function GetFromDevOps($url)
{
$patToken = [System.Convert]::ToBase64String([System.Text.Encoding]::ASCII.GetBytes(":$($pat)"))
$repoHeader = #{ "Authorization" = "Basic $patToken" }
$response = $(Invoke-WebRequest $url -Headers $repoHeader)
if ($response.StatusCode -ne 200)
{
Write-Error "FAILED: $($response.StatusDescription)"
}
return $response
}
function JsonFromDevOps($url)
{
$response = GetFromDevOps $url
return ConvertFrom-Json -InputObject $response.Content
}
function DownloadFromDevOps($url, $filename)
{
$patToken = [System.Convert]::ToBase64String([System.Text.Encoding]::ASCII.GetBytes(":$($pat)"))
$repoHeader = #{ "Authorization" = "Basic $patToken" }
$ProgressPreference = 'SilentlyContinue'
Invoke-WebRequest $url -Headers $repoHeader -OutFile $filename
$ProgressPreference = 'Continue'
}
function DownloadAndSaveFile($itemUrl, $outputPath, $path, $overwrite)
{
$outFile = "$outputPath$($path)"
$fileExists = Test-Path $outFile
if (!$fileExists -or $overwrite)
{
$outPath = [System.IO.Path]::GetDirectoryName($outFile)
CreateLocation $outPath
if ($fileExists)
{
Write-Host " overwriting to $outputPath"
}
else
{
Write-Host " downloading to $outputPath"
}
DownloadFromDevOps $itemUrl $outFile
}
}
function DownloadFiles($changes, $beforePath, $beforeCommitId, $afterPath, $afterCommitId)
{
foreach ($change in $changes)
{
$item = $change.item
if ($item.isFolder)
{
continue;
}
$path = $item.path
$originalPath = $change.originalPath
if (!$path)
{
$path = $change.originalPath
}
$displayPath = $path ?? $originalPath
$changeType = $change.changeType
Write-Host "[$($changeType)] $($displayPath)"
if (($changeType -eq "edit, rename"))
{
$itemUrl = "$($urlRepository)/items?path=$($originalPath)&versionDescriptor.version=$($beforeCommitId)&versionDescriptor.versionOptions=0&versionDescriptor.versionType=2&download=true"
DownloadAndSaveFile $itemUrl $beforePath $originalPath
}
# just get the source/before version
if ($changeType -eq "delete")
{
$itemUrl = "$($urlRepository)/items?path=$($originalPath)&versionDescriptor.version=$($beforeCommitId)&versionDescriptor.versionOptions=0&versionDescriptor.versionType=2&download=true"
DownloadAndSaveFile $itemUrl $beforePath $originalPath
DeleteFile "$($afterPath)$($originalPath)"
}
if ($changeType -eq "edit")
{
$itemUrl = "$($urlRepository)/items?path=$($path)&versionDescriptor.version=$($beforeCommitId)&versionDescriptor.versionOptions=0&versionDescriptor.versionType=2&download=true"
DownloadAndSaveFile $itemUrl $beforePath $path
}
if (($changeType -eq "add") -or ($changeType -eq "edit") -or ($changeType -eq "edit, rename"))
{
$itemUrl = "$($urlRepository)/items?path=$($path)&versionDescriptor.version=$($afterCommitId)&versionDescriptor.versionOptions=0&versionDescriptor.versionType=2&download=true"
DownloadAndSaveFile $itemUrl $afterPath $path $true
}
$validChangeTypes = #('add', 'delete', 'edit', 'edit, rename')
if (!($validChangeTypes.Contains($changeType)))
{
Write-Warning "Unknown change type $($changeType)"
}
}
}
# --- Azure DevOps helper methods ---
$urlBase = "https://dev.azure.com/$($urlOrganization)/$($urlProject)/_apis"
$urlRepository = "$($urlBase)/git/repositories/$($repoName)"
$urlPullRequests = "$($urlRepository)/pullRequests"
$urlPullRequest = "$($urlPullRequests)/$($pullRequestId)"
$urlIterations = "$($urlPullRequest)/iterations"
CleanLocation $prPath
$iterations = JsonFromDevOps $urlIterations
foreach ($iteration in $iterations.value)
{
# the modified file
$srcId = $iteration.sourceRefCommit.commitId
# the original file
$comId = $iteration.commonRefCommit.commitId
$comId = $iteration.targetRefCommit.commitId
$urlIterationChanges = "$($urlIterations)/$($iteration.id)/changes"
$iterationChanges = JsonFromDevOps $urlIterationChanges
DownloadFiles $iterationChanges.changeEntries $sourcePath $comId $targetPath $srcId
}