(SQL Server) Get Firebase Access Token from JSON Service Account Private Key

Demonstrates how to get a Firebase access token using a JSON service account private key. Your Firebase service account can be used to authenticate multiple Firebase features, such as Database, Storage and Auth, programmatically.

A Firebase JSON service account private key can be created in the Firebase settings/admin portion of the console.firebase.google.com site as shown here:

Scroll down to see the example code...

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
    DECLARE @iTmp0 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.

    -- First load the Firebase JSON private key into a string.
    DECLARE @fac int
    -- Use "Chilkat_9_5_0.FileAccess" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.FileAccess', @fac OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @jsonKey nvarchar(4000)
    EXEC sp_OAMethod @fac, 'ReadEntireTextFile', @jsonKey OUT, 'qa_data/firebase/firebase-chilkat-firebase-adminsdk-n28n4-1b664ee163.json', 'utf-8'
    EXEC sp_OAGetProperty @fac, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 <> 1
      BEGIN
        EXEC sp_OAGetProperty @fac, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @fac
        RETURN
      END

    -- A Firebase JSON private key should look something like this:

    -- { 
    --   "type": "service_account",
    --   "project_id": "firebase-chilkat",
    --   "private_key_id": "1c664ee164907413c91ddefcf5b765ecba8779e2",
    --   "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvQIBA ... Ya2UZii/lXn73/ZOK8=\n-----END PRIVATE KEY-----\n",
    --   "client_email": "firebase-adminsdk-n28n4@firebase-chilkat.iam.gserviceaccount.com",
    --   "client_id": "134846322329335418431",
    --   "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    --   "token_uri": "https://accounts.google.com/o/oauth2/token",
    --   "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    --   "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/firebase-adminsdk-n28n4%40firebase-chilkat.iam.gserviceaccount.com"
    -- } 
    -- 

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

    EXEC sp_OASetProperty @gAuth, 'JsonKey', @jsonKey

    -- Choose a scope.
    -- The scope could be "https://www.googleapis.com/auth/firebase.database"
    -- or a space-delimited list of scopes:
    -- "https://www.googleapis.com/auth/firebase.database https://www.googleapis.com/auth/userinfo.email"

    EXEC sp_OASetProperty @gAuth, 'Scope', 'https://www.googleapis.com/auth/firebase.database https://www.googleapis.com/auth/userinfo.email'

    -- Request an access token that is valid for this many seconds.
    EXEC sp_OASetProperty @gAuth, 'ExpireNumSeconds', 3600

    -- If the application is requesting delegated access:
    -- The email address of the user for which the application is requesting delegated access,
    -- then set the email address here. (Otherwise leave it empty.)
    EXEC sp_OASetProperty @gAuth, 'SubEmailAddress', ''

    -- Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
    -- The Chilkat socket object is used so that the connection can be established
    -- through proxies or an SSH tunnel if desired.
    DECLARE @tlsSock int
    -- Use "Chilkat_9_5_0.Socket" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Socket', @tlsSock OUT

    DECLARE @success int
    EXEC sp_OAMethod @tlsSock, 'Connect', @success OUT, 'www.googleapis.com', 443, 1, 5000
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @tlsSock, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @fac
        EXEC @hr = sp_OADestroy @gAuth
        EXEC @hr = sp_OADestroy @tlsSock
        RETURN
      END

    -- Send the request to obtain the access token.
    EXEC sp_OAMethod @gAuth, 'ObtainAccessToken', @success OUT, @tlsSock
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @gAuth, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @fac
        EXEC @hr = sp_OADestroy @gAuth
        EXEC @hr = sp_OADestroy @tlsSock
        RETURN
      END

    -- Examine the access token:

    EXEC sp_OAGetProperty @gAuth, 'AccessToken', @sTmp0 OUT
    PRINT 'Firebase Access Token: ' + @sTmp0

    -- Save the token to a file (or wherever desired).  This token is valid for 1 hour.
    EXEC sp_OAGetProperty @gAuth, 'AccessToken', @sTmp0 OUT
    EXEC sp_OAMethod @fac, 'WriteEntireTextFile', @success OUT, 'qa_data/tokens/firebaseToken.txt', @sTmp0, 'utf-8', 0

    EXEC @hr = sp_OADestroy @fac
    EXEC @hr = sp_OADestroy @gAuth
    EXEC @hr = sp_OADestroy @tlsSock


END
GO