(Ruby) Download Object from Google Cloud Storage

Demonstrates how to download an object from Google Cloud Storage to a file.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# 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 = Chilkat::CkStringBuilder.new()
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 = Chilkat::CkHttp.new()

http.put_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 = Chilkat::CkBinData.new()
success = http.DownloadBd(url,fileData)
if (success == false)
    print http.lastErrorText() + "\n";
    exit
end

sbErrorResponse = Chilkat::CkStringBuilder.new()
responseCode = http.get_LastStatus()
if (responseCode == 401)
    print "If invalid credentials, then it is likely the access token expired." + "\n";
    print "Your app should automatically fetch a new access token and re-try." + "\n";
end

if (responseCode != 200)
    # Get the error response
    sbErrorResponse.AppendBd(fileData,"utf-8",0,0)
    print "Error response code = " + responseCode.to_s() + "\n";
    print "Error:" + "\n";
    print sbErrorResponse.getAsString() + "\n";
    exit
end

print "Success." + "\n";

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