(Excel) Uni Economy API Client Credentials Flow

Demonstrates how to do OAuth 2.0 using the client credentials flow for the Uni Economy API. (This means that the server can authenticate against the identity server without human interaction.)

For more information, see https://developer.unieconomy.no/wiki/introduction/getting-started/server-application

Download Excel Class Modules Chilkat Excel Class Modules

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' Step 1 ------------------------------------------------------------------------------------------
' First create a client token...

Dim cert As Chilkat.Cert
Set cert = Chilkat.NewCert
cert.VerboseLogging = True
' Note: .pfx and .p12 files are identical.  The only difference is the file extension.
' Also, if your .p12 password is longer than 64 chars, you'll need Chilkat v9.5.0.83 or later.
' To shorten the password, import your .p12 onto your Windows computer by double-clicking on the .p12 file,
' make sure when importing that keys are exportable, then re-export with private keys to a .pfx with a new password.

success = cert.LoadPfxFile("qa_data/pfx/UniCert_Norge_Test_secret.pfx","secret")
If (success = False) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If


Set privKey = cert.ExportPrivateKey()
If (cert.LastMethodSuccess = False) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

Dim jwt As Chilkat.Jwt
Set jwt = Chilkat.NewJwt

' Build the JOSE header
Dim jose As Chilkat.JsonObject
Set jose = Chilkat.NewJsonObject
' Use RS256.  Pass the string "RS384" or "RS512" to use RSA with SHA-384 or SHA-512.
success = jose.AppendString("alg","RS256")
success = jose.AppendString("typ","JWT")

' Now build the JWT claims (also known as the payload)

' Our JWT claims will contain members as shown here:
' {
'   "jti": "ad612fce-3e71-4f6a-8af1-7eb0414b4eea",  <-- generated unique global identifier
'   "sub": "99999999-aaaa-bbbb-cccc-ddddeeeeffff",  <-- This is the clientId
'   "iat": 1588102982,  <-- These are date/time values.
'   "nbf": 1588102982,
'   "exp": 1588103042,
'   "iss": " 99999999-aaaa-bbbb-cccc-ddddeeeeffff",
'   "aud": "https://test-login.unieconomy.no/connect/token"
' }

' Use your own client ID.

myClientId = "99999999-aaaa-bbbb-cccc-ddddeeeeffff"

Dim claims As Chilkat.JsonObject
Set claims = Chilkat.NewJsonObject
Dim crypt As Chilkat.Crypt2
Set crypt = Chilkat.NewCrypt2
Dim success As Boolean
success = claims.AppendString("jti",crypt.GenerateUuid())
success = claims.AppendString("sub",myClientId)

' Set the timestamp of when the JWT was created to now minus 60 seconds

curDateTime = jwt.GenNumericDate(-60)
success = claims.AddIntAt(-1,"iat",curDateTime)

' Set the "not process before" timestamp to now minus 60 seconds
success = claims.AddIntAt(-1,"nbf",curDateTime)

' Set the timestamp defining an expiration time (end time) for the token
' to be now + 1 hour (3600 seconds)
success = claims.AddIntAt(-1,"exp",curDateTime + 3600)

success = claims.AppendString("iss",myClientId)
success = claims.AppendString("aud","https://test-login.unieconomy.no/connect/token")

' Produce the smallest possible JWT:
jwt.AutoCompact = True

' Create the JWT token.  This is where the RSA signature is created.

jwt_token = jwt.CreateJwtPk(jose.Emit(),claims.Emit(),privKey)

Debug.Print jwt_token

' Step 2 ------------------------------------------------------------------------------------------
Dim http As Chilkat.Http
Set http = Chilkat.NewHttp

' Fetch the discovery document...

Set resp = http.QuickRequest("GET","https://test-login.unieconomy.no/.well-known/openid-configuration")
If (http.LastMethodSuccess <> True) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

If (resp.StatusCode <> 200) Then
    Debug.Print "Received response status code "; resp.StatusCode
    Debug.Print "Response body containing error text or JSON:"
    Debug.Print resp.BodyStr

    Exit Sub
End If

Dim json As Chilkat.JsonObject
Set json = Chilkat.NewJsonObject
success = json.Load(resp.BodyStr)

json.EmitCompact = False
Debug.Print json.Emit()

' We have the discovery document, which contains something like this:

' You can use this online tool to generate parsing code from sample JSON: 
' Generate Parsing Code from JSON

' {
'   "issuer": "https://test-login.unieconomy.no",
'   "jwks_uri": "https://test-login.unieconomy.no/.well-known/openid-configuration/jwks",
'   "authorization_endpoint": "https://test-login.unieconomy.no/connect/authorize",
'   "token_endpoint": "https://test-login.unieconomy.no/connect/token",
'   "userinfo_endpoint": "https://test-login.unieconomy.no/connect/userinfo",
'   "end_session_endpoint": "https://test-login.unieconomy.no/connect/endsession",
'   "check_session_iframe": "https://test-login.unieconomy.no/connect/checksession",
'   "revocation_endpoint": "https://test-login.unieconomy.no/connect/revocation",
'   "introspection_endpoint": "https://test-login.unieconomy.no/connect/introspect",
'   "device_authorization_endpoint": "https://test-login.unieconomy.no/connect/deviceauthorization",
'   "frontchannel_logout_supported": true,
'   "frontchannel_logout_session_supported": true,
'   "backchannel_logout_supported": true,
'   "backchannel_logout_session_supported": true,
'   "scopes_supported": [
'     "openid",
'     "profile",
'     "email",
'     "offline_access",
'     "AppFramework.All",
'     "AppFramework",
'     "AppFramework.Sales",
'     "IdentityAPI",
'     "widgetApi",
'     "TestScope.test",
'     "TestScope.Cars",
'     "HaglandAPI",
'     "LicenseAdmin",
'     "LicenseAdmin.Product.Read",
'     "SoftRig.Product.Write",
'     "TestAPI.test",
'     "offline_access"
'   ],
'   "claims_supported": [
'     "sub",
'     "updated_at",
'     "name",
'     "family_name",
'     "given_name",
'     "middle_name",
'     "nickname",
'     "preferred_username",
'     "picture",
'     "website",
'     "gender",
'     "birthdate",
'     "zoneinfo",
'     "locale",
'     "profile",
'     "email",
'     "email_verified"
'   ],
'   "grant_types_supported": [
'     "authorization_code",
'     "client_credentials",
'     "refresh_token",
'     "implicit",
'     "password",
'     "urn:ietf:params:oauth:grant-type:device_code",
'     "delegation"
'   ],
'   "response_types_supported": [
'     "code",
'     "token",
'     "id_token",
'     "id_token token",
'     "code id_token",
'     "code token",
'     "code id_token token"
'   ],
'   "response_modes_supported": [
'     "form_post",
'     "query",
'     "fragment"
'   ],
'   "token_endpoint_auth_methods_supported": [
'     "client_secret_basic",
'     "client_secret_post",
'     "private_key_jwt",
'     "private_key_jwt"
'   ],
'   "id_token_signing_alg_values_supported": [
'     "RS256"
'   ],
'   "subject_types_supported": [
'     "public"
'   ],
'   "code_challenge_methods_supported": [
'     "plain",
'     "S256"
'   ],
'   "request_parameter_supported": true
' }

' ------------------------------------------------------
' The next steps are to (1) get the token_endpoint,
' and (2) verify that the client_credentials grant type is supported.


tokenEndpoint = json.StringOf("token_endpoint")


Set grantTypes = json.ArrayOf("grant_types_supported")

clientCredentialsIdx = grantTypes.FindString("client_credentials",True)

' If clientCredentialsIdx is less then zero (-1) then the "client_credentials" string was not found.
If (clientCredentialsIdx < 0) Then
    Debug.Print "The client credentials grant type is not supported."
    Exit Sub
End If

' ------------------------------------------------------
' Request the access token using our Client ID and JWT

Dim req As Chilkat.HttpRequest
Set req = Chilkat.NewHttpRequest
req.HttpVerb = "POST"
req.AddParam "client_id",myClientId
req.AddParam "scope","AppFramework.Sales"
req.AddParam "grant_type","client_credentials"
req.AddParam "client_assertion_type","urn:ietf:params:oauth:client-assertion-type:jwt-bearer"
req.AddParam "client_assertion",jwt_token

Set resp = http.PostUrlEncoded(tokenEndpoint,req)
If (http.LastMethodSuccess = False) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

' Make sure we got a 200 response status code, otherwise it's an error.
If (resp.StatusCode <> 200) Then
    Debug.Print "POST to token endpoint failed."
    Debug.Print "Received response status code "; resp.StatusCode
    Debug.Print "Response body containing error text or JSON:"
    Debug.Print resp.BodyStr

    Exit Sub
End If

success = json.Load(resp.BodyStr)

Debug.Print json.Emit()

' The JSON response will look like this:

' {
'   "access_token": "...",
'   "expires_in": 3600,
'   "token_type": "Bearer",
'   "scope": "AppFramework.Sales"
' }

' Get the access token:

accessToken = json.StringOf("access_token")
Debug.Print "accessToken = "; accessToken

' ------------------------------------------------------
' Use the access token in a request.
' We'll just send a GET request to  https://test.unieconomy.no/api/init/companies

' Tell the http object to use the OAuth2 access token in the "Authorization: Bearer ..." header.
http.AuthToken = accessToken

Dim sbResponse As Chilkat.StringBuilder
Set sbResponse = Chilkat.NewStringBuilder
success = http.QuickGetSb("https://test.unieconomy.no/api/init/companies",sbResponse)
If (success = False) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

' Examine the response status code.
If (http.LastStatus <> 200) Then
    Debug.Print sbResponse.GetAsString()
    Debug.Print "response status: "; http.LastStatus
    Debug.Print "Received error response."
    Exit Sub
End If

success = json.LoadSb(sbResponse)
Debug.Print json.Emit()

Debug.Print "Success."