(PowerShell) Download Object from Google Cloud Storage

Demonstrates how to download an object from Google Cloud Storage 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 uses a previously obtained access token having permission for the 
# scope "https://www.googleapis.com/auth/cloud-platform"

# In this example, Get Google Cloud Storage OAuth2 Access Token, 
# the service account access token was saved to a text file.  This example fetches the access token from the file..
$sbToken = New-Object Chilkat.StringBuilder
$sbToken.LoadFile("qa_data/tokens/googleCloudStorageAccessToken.txt","utf-8")

# Send a GET equivalent to this curl command.

# curl -X GET \
#     -H "Authorization: Bearer [OAUTH2_TOKEN]" \
#     -o "[SAVE_TO_LOCATION]" \
#     "https://www.googleapis.com/storage/v1/b/[BUCKET_NAME]/o/[OBJECT_NAME]?alt=media"

$http = New-Object Chilkat.Http

$http.AuthToken = $sbToken.GetAsString()

# Construct a URL to download an object named "starfish.jpg" from the "chilkat-ocean" bucket.
$http.SetUrlVar("bucket_name","chilkat-ocean")
$http.SetUrlVar("object_name","starfish.jpg")
$url = "https://www.googleapis.com/storage/v1/b/{$bucket_name}/o/{$object_name}?alt=media"

# If there is an error response, then we didn't actually download the file data,
# but instead we downloaded an error response..
$fileData = New-Object Chilkat.BinData
$success = $http.DownloadBd($url,$fileData)
if ($success -eq $false) {
    $($http.LastErrorText)
    exit
}

$sbErrorResponse = New-Object Chilkat.StringBuilder
$responseCode = $http.LastStatus
if ($responseCode -eq 401) {
    $("If invalid credentials, then it is likely the access token expired.")
    $("Your app should automatically fetch a new access token and re-try.")
}

if ($responseCode -ne 200) {
    # Get the error response
    $sbErrorResponse.AppendBd($fileData,"utf-8",0,0)
    $("Error response code = " + $responseCode)
    $("Error:")
    $($sbErrorResponse.GetAsString())
    exit
}

$("Success.")

# Save the downloaded data to a file.
$success = $fileData.WriteFile("qa_output/starfish.jpg")