SQL Server

HMRC OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to get an HMRC OAuth2 access token from a desktop (installed) application or script. This example gets an HMRC MTD VAT read/write access token. SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    -- To further clarify, see OAuth 2.0 Authorization Flow

    DECLARE @oauth2 int
    EXEC @hr = sp_OACreate 'Chilkat.OAuth2', @oauth2 OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- This should be the port in the localhost callback URL for your app.
    -- Important: Make sure the callback URI in your HMRC developer app 
    -- is exactly "http://localhost:3017/".  Don't forget the ending "/" char.
    -- The callback URL would look like "http://localhost:3017/" if the port number is 3017.

    -- IMPORTANT: Don't forget to setup your HMRC application to use the Redirect URI "http://localhost:3017/" as shown
    -- here: Configure Redirect URI for HMRC application
    EXEC sp_OASetProperty @oauth2, 'ListenPort', 3017

    EXEC sp_OASetProperty @oauth2, 'AuthorizationEndpoint', 'https://test-api.service.hmrc.gov.uk/oauth/authorize'
    EXEC sp_OASetProperty @oauth2, 'TokenEndpoint', 'https://test-api.service.hmrc.gov.uk/oauth/token'

    -- Replace with your actual client ID
    EXEC sp_OASetProperty @oauth2, 'ClientId', 'HMRC-CLIENT-ID'

    -- The scopes are documented in the HMRC reference documentation for each API.
    -- This example gets a read/write access token for the HMRC MTD VAT API.
    EXEC sp_OASetProperty @oauth2, 'Scope', 'read:vat write:vat'

    -- Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
    DECLARE @url nvarchar(4000)
    EXEC sp_OAMethod @oauth2, 'StartAuth', @url OUT
    EXEC sp_OAGetProperty @oauth2, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 <> 1
      BEGIN
        EXEC sp_OAGetProperty @oauth2, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END

    -- Launch the default browser on the system and navigate to the url.
    -- The LaunchBrowser method was added in Chilkat v10.1.2.
    EXEC sp_OAMethod @oauth2, 'LaunchBrowser', @success OUT, @url
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @oauth2, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END

    -- Wait for the user to approve or deny authorization in the browser.
    DECLARE @numMsWaited int
    SELECT @numMsWaited = 0
    EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
    WHILE (@numMsWaited < 90000) and (@iTmp0 < 3)
      BEGIN
        EXEC sp_OAMethod @oauth2, 'SleepMs', NULL, 100
        SELECT @numMsWaited = @numMsWaited + 100
      END

    -- If the browser does not respond within the specified time, AuthFlowState will be:
    -- 
    -- 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
    -- 2: Waiting for Final Response – The thread is awaiting the final access token response.
    -- In either case, cancel the background task initiated by StartAuth.

    EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
    IF @iTmp0 < 3
      BEGIN
        EXEC sp_OAMethod @oauth2, 'Cancel', @success OUT

        PRINT 'No response from the browser!'
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END

    -- Check AuthFlowState to determine if authorization was granted, denied, or failed:
    -- 
    -- 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
    -- 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
    -- 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

    EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
    IF @iTmp0 = 5
      BEGIN

        PRINT 'OAuth2 failed to complete.'
        EXEC sp_OAGetProperty @oauth2, 'FailureInfo', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END

    EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
    IF @iTmp0 = 4
      BEGIN

        PRINT 'OAuth2 authorization was denied.'
        EXEC sp_OAGetProperty @oauth2, 'AccessTokenResponse', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END

    EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
    IF @iTmp0 <> 3
      BEGIN

        EXEC sp_OAGetProperty @oauth2, 'AuthFlowState', @iTmp0 OUT
        PRINT 'Unexpected AuthFlowState:' + @iTmp0
        EXEC @hr = sp_OADestroy @oauth2
        RETURN
      END


    PRINT 'OAuth2 authorization granted!'

    EXEC sp_OAGetProperty @oauth2, 'AccessToken', @sTmp0 OUT
    PRINT 'Access Token = ' + @sTmp0

    -- Get the full JSON response:
    DECLARE @json int
    EXEC @hr = sp_OACreate 'Chilkat.JsonObject', @json OUT

    EXEC sp_OAGetProperty @oauth2, 'AccessTokenResponse', @sTmp0 OUT
    EXEC sp_OAMethod @json, 'Load', @success OUT, @sTmp0
    EXEC sp_OASetProperty @json, 'EmitCompact', 0
    EXEC sp_OAMethod @json, 'Emit', @sTmp0 OUT
    PRINT @sTmp0

    -- The JSON response looks like this:

    -- {
    --   "token_type": "Bearer",
    --   "scope": "user_impersonation",
    --   "expires_in": "3599",
    --   "ext_expires_in": "0",
    --   "expires_on": "1524783438",
    --   "not_before": "1524779538",
    --   "resource": "https://mydomain.api.crm.dynamics.com",
    --   "access_token": "...",
    --   "refresh_token": "...",
    --   "id_token": "..."
    -- }

    -- If an "expires_on" member does not exist, then add the JSON member by
    -- getting the current system date/time and adding the "expires_in" seconds.
    -- This way we'll know when the token expires.
    EXEC sp_OAMethod @json, 'HasMember', @iTmp0 OUT, 'expires_on'
    IF @iTmp0 <> 1
      BEGIN
        DECLARE @dtExpire int
        EXEC @hr = sp_OACreate 'Chilkat.CkDateTime', @dtExpire OUT

        EXEC sp_OAMethod @dtExpire, 'SetFromCurrentSystemTime', @success OUT
        EXEC sp_OAMethod @json, 'IntOf', @iTmp0 OUT, 'expires_in'
        EXEC sp_OAMethod @dtExpire, 'AddSeconds', @success OUT, @iTmp0
        EXEC sp_OAMethod @dtExpire, 'GetAsUnixTimeStr', @sTmp0 OUT, 0
        EXEC sp_OAMethod @json, 'AppendString', @success OUT, 'expires_on', @sTmp0
      END

    EXEC sp_OAMethod @json, 'Emit', @sTmp0 OUT
    PRINT @sTmp0

    -- Save the JSON to a file for future requests.
    DECLARE @fac int
    EXEC @hr = sp_OACreate 'Chilkat.FileAccess', @fac OUT

    EXEC sp_OAMethod @json, 'Emit', @sTmp0 OUT
    EXEC sp_OAMethod @fac, 'WriteEntireTextFile', @success OUT, 'qa_data/tokens/hmrc.json', @sTmp0, 'utf-8', 0

    EXEC @hr = sp_OADestroy @oauth2
    EXEC @hr = sp_OADestroy @json
    EXEC @hr = sp_OADestroy @dtExpire
    EXEC @hr = sp_OADestroy @fac


END
GO