MSIgniteDownloadResources.ps1

Param (
    ## The directory into which the user wishes to download the files.
    [string]$directory = $PSScriptRoot,
    ## Optional parameter allowing the user to specifiy the code (or comma seperated codes) of the video(s) they wish to download.
    [string]$sessionCodes = ""
)

### Variables ###
$api = 'https://api.myignite.microsoft.com/api/session/all'

function CheckPathLength($path) {
    while ($path.Length -gt 230) {
        $path = Read-Host("The directory entered is too long.`nEnter a new directory or press Enter to use the location of this script");
        if ($path -eq "") { $path = $PSScriptRoot };
    }
    return $path;
}

function CheckPathSyntaxValid($path) {
    while (-Not (Test-Path $path -IsValid)) {
        $path = Read-Host("The syntax of the directory is invalid.`nPlease enter a valid directory or press Enter to use the location of this script")
        if ($path -eq "") { $path = $PSScriptRoot };
    }
    return $path;
}

function CheckPathExists($path) {
    if (-Not (Test-Path -Path $path)) {
        Write-Host("The directory entered does not exist`nCreate directory?");
        $createDirectoryResponse = "invalid";
        while (($createDirectoryResponse -ne "Y") -or ($createDirectoryResponse -ne "y") -or ($createDirectoryResponse -ne "N") -or ($createDirectoryResponse -ne "n")) {
            $createDirectoryResponse = Read-Host("'y' or 'n'");
            if (($createDirectoryResponse -eq "Y") -or ($createDirectoryResponse -eq "y")) {
                New-Item $path -type directory > $null;
                return $path;
            }
            elseif (($createDirectoryResponse -eq "N") -or ($createDirectoryResponse -eq "n")) {
                $enteredPath = Read-Host("Enter another directory");
                while ($path -eq $enteredPath) {
                    $enteredPath = Read-Host("You have entered the same path.`nEnter another directory or press Enter to use the location of this script");
                }
                if ($path -eq "") { $path = $PSScriptRoot };
                return $enteredPath;
            }
        }
    }
    return $path;
}

function DownloadDirectory($path) {
    $repeatLoop = $true;
    while ($repeatLoop) {
        $repeatLoop = $false

        $newPath = CheckPathLength $path;
        if ($newPath -ne $path) { $repeatLoop = $true; $path = $newPath; continue; }

        $newPath = CheckPathSyntaxValid $path;
        if ($newPath -ne $path) { $repeatLoop = $true; $path = $newPath; continue; }

        $newPath = CheckPathExists $path;
        if ($newPath -ne $path) { $repeatLoop = $true; $path = $newPath; continue; }
    }
    $directory = $newPath;
}

function FetchSessionData() {
    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    Write-Host("Pulling session data...");
    $sessionsJson = Invoke-WebRequest -Uri $api -Method 'GET';
    $sessions = $sessionsJson | ConvertFrom-Json;
    return $sessions
}

function FilterSessions($sessions, $sessionCodes) {
    if ($sessionCodes.length -eq 0) {
        Write-Host("All sessions containing slides and/or videos will be downloaded");
        return $sessions;
    }
    else {
        $splitSessionCodes = $sessionCodes.Split(",");
        $filteredSessions = @();
        $codesOfSessionsFound = @();
        foreach ($s in $sessions) {
            if ($splitSessionCodes -contains $s.sessionCode) {
                $filteredSessions += $s;
                $codesOfSessionsFound += $s.sessionCode;
            }
        }
        if ($filteredSessions.Count -eq 0) {
            Write-Host("None of the session codes entered could be found. This program will now terminate.");
            Exit;

        }
        if ($splitSessionCodes.Count -ne $codesOfSessionsFound.Count) {
            Write-Host("Some of the session codes entered could not be found. The following sessions will not be downloaded:");
            foreach ($sc in $splitSessionCodes) {
                if (-not ($codesOfSessionsFound -contains $sc)) {
                    Write-Host($sc);
                }
            }
        }
        return $filteredSessions;
    }
}

function CleanFilename($filename) {
    return $filename.Replace(":", "-").Replace("?", "").Replace("/", "-").Replace("<", "").Replace("|", "").Replace('"', "").Replace("*", "")
}

function DownloadSession($sessionObject, $sessionSearchCount, $directory) {
    if (($sessionObject.slideDeck.Length -ne 0) -or ($sessionObject.downloadVideoLink.Length -ne 0)) {
        $code = $sessionObject.sessionCode;
        $title = $sessionObject.title;

        if ($code.Length -eq 0) {
            $code = "NoCodeSession$sessionSearchCount"
        }
        if ($title.Length -eq 0) {
            $title = "NoTitleSession$sessionSearchCount";
        }

        Write-Host("===== $title ($code) =====");

        #Create directory.
        $folder = Join-Path -Path $directory -ChildPath $s.sessionCode;
        if (-not (Test-Path $folder)) {
            Write-Host "Folder ($folder) doesn't exist. Creating it..."  ;
            New-Item $folder -type directory | Out-Null;
        }

        $videoFile = "$directory\$code\$code.mp4";
        $slideFile = "$directory\$code\$code.pptx";

        #Video download.
        if ($sessionObject.downloadVideoLink.Length -ne 0) {
            if (!(test-path $videoFile)) {
                Write-Host "Downloading video: $title ($code).";
                Start-BitsTransfer -Source $sessionObject.downloadVideoLink -Destination $videoFile;
            }
            else {
                Write-Host "Video exists: $videoFile"
            }
        }
        else {
            Write-Host "The session $title ($code) does not contain a video recording."
        }

        #Slides download.
        if ($sessionObject.slideDeck.Length -ne 0) {
            if (!(test-path $slideFile)) {
                Write-Host "Downloading slides for: $title ($code).";
                Start-BitsTransfer -Source $sessionObject.slideDeck -Destination $slideFile;
            }
            else {
                Write-Host "Slides exist: $slideFile"
            }
        }
        else {
            Write-Host "The session $title ($code) does not contain a slide deck."
        }

        Write-Host "Downloading data for: $title ($code).";
        Write-Host("`r`n");
        return $true;
    }
    return $false;
}

### Main ###
DownloadDirectory $directory;
$sessions = FetchSessionData;
$sessions = FilterSessions $sessions $sessionCodes;
$sessionSearchCount = 0;
$sessionDownloadCount = 0;
foreach ($s in $sessions) {
    if (DownloadSession $s $sessionDownloadCount $directory) {
        $sessionDownloadCount++;
        $metaData += "Session ID: " + $s.sessionId;
        $metaData += "`tSession Code: " + $s.sessionCode;
        $metaData += "`tSession Title: " + $s.title;
        $metaData += "`rSession Description: " + $s.description;
        $metaData += "`r`n`r`n"
    }
    $sessionSearchCount ++;
}
$dataFile = "$directory\download-report.txt";
Out-File -FilePath $dataFile -InputObject $metaData -Encoding ASCII;
Write-Host("$sessionSearchCount session(s) searched.");
Write-Host("$sessionDownloadCount session(s) downloaded.");