(SQL Server) URL Signing for Google Maps API

Demonstrates how to sign a URL for the Google Maps API.

Download Chilkat Crypt ActiveX

CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @crypt int
    EXEC @hr = sp_OACreate 'Chilkat.Crypt2', @crypt OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    --  Any string argument automatically begins the 30-day trial.
    DECLARE @success int

    EXEC sp_OAMethod @crypt, 'UnlockComponent', @success OUT, 'Anything for 30-day trial.'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    --  The output will be modified Base64.
    --  Modified Base64 for URLs replaces the '+' and '/' characters
    --  of standard Base64 with '-' and '_' respectively, so that these
    --  Base64 signatures no longer need to be URL-encoded.
    EXEC sp_OASetProperty @crypt, 'EncodingMode', 'modBase64'

    --  NOTE: At the time of this writing, the "modBase64" encoding mode is
    --  available in the pre-release build only.  Send email to
    --  support@chilkatsoft.com if you need a pre-release.  This feature will be
    --  included in the next official release.

    --  Set the hash algorithm to sha-1
    EXEC sp_OASetProperty @crypt, 'HashAlgorithm', 'sha-1'

    DECLARE @sig nvarchar(4000)

    --  Set the HMAC key (this is the private key provided by Google)
    EXEC sp_OAMethod @crypt, 'SetHmacKeyEncoded', NULL, 'vNIXE0xscrmjlyV-12Nj_BvUPaw=', 'modBase64'

    --  Compute the URL signature
    EXEC sp_OAMethod @crypt, 'HmacStringENC', @sig OUT, '/maps/api/geocode/json?address=New+York&sensor=false&client=clientID'

    --  The result should be KrU1TzVQM7Ur0i8i7K3huiw3MsA=

    PRINT @sig
END
GO