(SQL Server) Download Object from Google Cloud Storage

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    -- 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..
    DECLARE @sbToken int
    -- Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.StringBuilder', @sbToken OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @success int
    EXEC sp_OAMethod @sbToken, 'LoadFile', @success OUT, '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"

    DECLARE @http int
    -- Use "Chilkat_9_5_0.Http" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Http', @http OUT

    EXEC sp_OAMethod @sbToken, 'GetAsString', @sTmp0 OUT
    EXEC sp_OASetProperty @http, 'AuthToken', @sTmp0

    -- Construct a URL to download an object named "starfish.jpg" from the "chilkat-ocean" bucket.
    EXEC sp_OAMethod @http, 'SetUrlVar', @success OUT, 'bucket_name', 'chilkat-ocean'
    EXEC sp_OAMethod @http, 'SetUrlVar', @success OUT, 'object_name', 'starfish.jpg'
    DECLARE @url nvarchar(4000)
    SELECT @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..
    DECLARE @fileData int
    -- Use "Chilkat_9_5_0.BinData" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @fileData OUT

    DECLARE @success int
    EXEC sp_OAMethod @http, 'DownloadBd', @success OUT, @url, @fileData
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @http, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @sbToken
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @fileData
        RETURN
      END

    DECLARE @sbErrorResponse int
    -- Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.StringBuilder', @sbErrorResponse OUT

    DECLARE @responseCode int
    EXEC sp_OAGetProperty @http, 'LastStatus', @responseCode OUT
    IF @responseCode = 401
      BEGIN

        PRINT 'If invalid credentials, then it is likely the access token expired.'

        PRINT 'Your app should automatically fetch a new access token and re-try.'
      END

    IF @responseCode <> 200
      BEGIN
        -- Get the error response
        EXEC sp_OAMethod @sbErrorResponse, 'AppendBd', @success OUT, @fileData, 'utf-8', 0, 0

        PRINT 'Error response code = ' + @responseCode

        PRINT 'Error:'
        EXEC sp_OAMethod @sbErrorResponse, 'GetAsString', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @sbToken
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @fileData
        EXEC @hr = sp_OADestroy @sbErrorResponse
        RETURN
      END


    PRINT 'Success.'

    -- Save the downloaded data to a file.
    EXEC sp_OAMethod @fileData, 'WriteFile', @success OUT, 'qa_output/starfish.jpg'

    EXEC @hr = sp_OADestroy @sbToken
    EXEC @hr = sp_OADestroy @http
    EXEC @hr = sp_OADestroy @fileData
    EXEC @hr = sp_OADestroy @sbErrorResponse


END
GO