(PowerShell) Download Photo to a File

Assuming we have the ID of a Photo, this example demonstrates how to download the photo image data to a file.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# This example assumes a previously obtained an access token
$oauth2 = New-Object Chilkat.OAuth2
$oauth2.AccessToken = "FACEBOOK-ACCESS-TOKEN"

$rest = New-Object Chilkat.Rest

# Connect to Facebook...
$success = $rest.Connect("graph.facebook.com",443,$true,$true)
if ($success -ne $true) {
    $($rest.LastErrorText)
    exit
}

# Provide the authentication credentials (i.e. the access key)
$rest.SetAuthOAuth2($oauth2)

# Assumes we've already obtained a Photo ID.
$photoId = "10210199026347451"

$sbPath = New-Object Chilkat.StringBuilder
$sbPath.Append("/v2.7/")
$sbPath.Append($photoId)

# First we're going to get the photo informaton so we can get the URL of the image file data.
# Select the fields we want.
# See https://developers.facebook.com/docs/graph-api/reference/photo/
$rest.AddQueryParam("fields","id,album,images")

$responseJson = $rest.FullRequestNoBody("GET",$sbPath.GetAsString())
if ($rest.LastMethodSuccess -ne $true) {
    $($rest.LastErrorText)
    exit
}

$json = New-Object Chilkat.JsonObject
$json.EmitCompact = $false
$json.Load($responseJson)

# Show the JSON in human-readable format.
$($json.Emit())

# Get the image URL.
$imageUrl = $json.StringOf("images[0].source")
$("Downloading from " + $imageUrl)

$sbImageUrl = New-Object Chilkat.StringBuilder
$sbImageUrl.Append($imageUrl)

# Build the output local file path.
$sbToPath = New-Object Chilkat.StringBuilder
$sbToPath.Append("qa_output/fb")
$sbToPath.Append($json.StringOf("id"))
$bCaseSensitive = $false
if ($sbImageUrl.Contains(".jpg",$bCaseSensitive) -eq $true) {
    $sbToPath.Append(".jpg")
}
else {
    $sbToPath.Append(".png")
}

$("Downloading to " + $sbToPath.GetAsString())

# Download using Chilkat HTTP.
$http = New-Object Chilkat.Http
$success = $http.Download($imageUrl,$sbToPath.GetAsString())
if ($success -ne $true) {
    $($http.LastErrorText)
}
else {
    $("Downloaded.")
}