VB.NET
VB.NET
ING Open Banking OAuth2 Client Credentials
See more OAuth2 Examples
Demonstrates how to get an access token for the ING Open Banking APIs using client credentials.Chilkat VB.NET Downloads
Dim success As Boolean = False
' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.
Dim cert As New Chilkat.Cert
success = cert.LoadFromFile("qa_data/certs_and_keys/ING/example_client_tls.cer")
If (success = False) Then
Debug.WriteLine(cert.LastErrorText)
Exit Sub
End If
Dim bdPrivKey As New Chilkat.BinData
success = bdPrivKey.LoadFile("qa_data/certs_and_keys/ING/example_client_tls.key")
If (success = False) Then
Debug.WriteLine("Failed to load example_client_tls.key")
Exit Sub
End If
' The OAuth 2.0 client_id for these certificates is e77d776b-90af-4684-bebc-521e5b2614dd.
' Please note down this client_id since you will need it in the next steps to call the API.
Dim privKey As New Chilkat.PrivateKey
success = privKey.LoadAnyFormat(bdPrivKey,"")
If (success = False) Then
Debug.WriteLine(privKey.LastErrorText)
Exit Sub
End If
' Associate the private key with the certificate.
success = cert.SetPrivateKey(privKey)
If (success = False) Then
Debug.WriteLine(cert.LastErrorText)
Exit Sub
End If
Dim http As New Chilkat.Http
success = http.SetSslClientCert(cert)
If (success = False) Then
Debug.WriteLine(http.LastErrorText)
Exit Sub
End If
' Calculate the Digest and add the "Digest" header. Do the equivalent of this:
' payload="grant_type=client_credentials"
' payloadDigest=`echo -n "$payload" | openssl dgst -binary -sha256 | openssl base64`
' digest=SHA-256=$payloadDigest
Dim crypt As New Chilkat.Crypt2
crypt.HashAlgorithm = "SHA256"
crypt.EncodingMode = "base64"
Dim payload As String = "grant_type=client_credentials"
Dim payloadDigest As String = crypt.HashStringENC(payload)
' Calculate the current date/time and add the Date header.
' reqDate=$(LC_TIME=en_US.UTF-8 date -u "+%a, %d %b %Y %H:%M:%S GMT")
Dim dt As New Chilkat.CkDateTime
dt.SetFromCurrentSystemTime()
' The desire date/time format is the "RFC822" format.
http.SetRequestHeader("Date",dt.GetAsRfc822(False))
' Calculate signature for signing your request
' Duplicate the following code:
' httpMethod="post"
' reqPath="/oauth2/token"
' signingString="(request-target): $httpMethod $reqPath
' date: $reqDate
' digest: $digest"
' signature=`printf "$signingString" | openssl dgst -sha256 -sign "${certPath}example_client_signing.key" -passin "pass:changeit" | openssl base64 -A`
Dim httpMethod As String = "POST"
Dim reqPath As String = "/oauth2/token"
Dim sbStringToSign As New Chilkat.StringBuilder
sbStringToSign.Append("(request-target): ")
sbStringToSign.Append(httpMethod)
sbStringToSign.ToLowercase()
sbStringToSign.Append(" ")
sbStringToSign.AppendLine(reqPath,False)
sbStringToSign.Append("date: ")
sbStringToSign.AppendLine(dt.GetAsRfc822(False),False)
sbStringToSign.Append("digest: SHA-256=")
sbStringToSign.Append(payloadDigest)
Dim signingPrivKey As New Chilkat.PrivateKey
success = signingPrivKey.LoadPemFile("qa_data/certs_and_keys/ING/example_client_signing.key")
If (success = False) Then
Debug.WriteLine(signingPrivKey.LastErrorText)
Exit Sub
End If
Dim rsa As New Chilkat.Rsa
success = rsa.UsePrivateKey(signingPrivKey)
If (success = False) Then
Debug.WriteLine(rsa.LastErrorText)
Exit Sub
End If
rsa.EncodingMode = "base64"
Dim b64Signature As String = rsa.SignStringENC(sbStringToSign.GetAsString(),"SHA256")
Dim sbAuthHdrVal As New Chilkat.StringBuilder
sbAuthHdrVal.Append("Signature keyId=""e77d776b-90af-4684-bebc-521e5b2614dd"",")
sbAuthHdrVal.Append("algorithm=""rsa-sha256"",")
sbAuthHdrVal.Append("headers=""(request-target) date digest"",")
sbAuthHdrVal.Append("signature=""")
sbAuthHdrVal.Append(b64Signature)
sbAuthHdrVal.Append("""")
Dim sbDigestHdrVal As New Chilkat.StringBuilder
sbDigestHdrVal.Append("SHA-256=")
sbDigestHdrVal.Append(payloadDigest)
' Do the following CURL statement:
' curl -i -X POST "${httpHost}${reqPath}" \
' -H 'Accept: application/json' \
' -H 'Content-Type: application/x-www-form-urlencoded' \
' -H "Digest: ${digest}" \
' -H "Date: ${reqDate}" \
' -H "authorization: Signature keyId=\"$keyId\",algorithm=\"rsa-sha256\",headers=\"(request-target) date digest\",signature=\"$signature\"" \
' -d "${payload}" \
' --cert "${certPath}tlsCert.crt" \
' --key "${certPath}tlsCert.key"
Dim req As New Chilkat.HttpRequest
req.AddParam("grant_type","client_credentials")
req.AddHeader("Accept","application/json")
req.AddHeader("Date",dt.GetAsRfc822(False))
req.AddHeader("Digest",sbDigestHdrVal.GetAsString())
req.AddHeader("Authorization",sbAuthHdrVal.GetAsString())
req.HttpVerb = "POST"
req.ContentType = "application/x-www-form-urlencoded"
Dim resp As New Chilkat.HttpResponse
success = http.HttpReq("https://api.sandbox.ing.com/oauth2/token",req,resp)
If (success = False) Then
Debug.WriteLine(http.LastErrorText)
Exit Sub
End If
' If successful, the status code = 200
Debug.WriteLine("Response Status Code: " & resp.StatusCode)
Debug.WriteLine(resp.BodyStr)
Dim json As New Chilkat.JsonObject
json.Load(resp.BodyStr)
json.EmitCompact = False
Debug.WriteLine(json.Emit())
' A successful response contains an access token such as:
' {
' "access_token": "eyJhbGc ... bxI_SoPOBH9xmoM",
' "expires_in": 905,
' "scope": "payment-requests:view payment-requests:create payment-requests:close greetings:view virtual-ledger-accounts:fund-reservation:create virtual-ledger-accounts:fund-reservation:delete virtual-ledger-accounts:balance:view",
' "token_type": "Bearer",
' "keys": [
' {
' "kty": "RSA",
' "n": "3l3rdz4...04VPkdV",
' "e": "AQAB",
' "use": "sig",
' "alg": "RS256",
' "x5t": "3c396700fc8cd709cf9cb5452a22bcde76985851"
' }
' ],
' "client_id": "e77d776b-90af-4684-bebc-521e5b2614dd"
' }
' Use this online tool to generate parsing code from sample JSON:
' Generate Parsing Code from JSON
Dim kty As String
Dim n As String
Dim e As String
Dim use As String
Dim alg As String
Dim x5t As String
Dim access_token As String = json.StringOf("access_token")
Dim expires_in As Integer = json.IntOf("expires_in")
Dim scope As String = json.StringOf("scope")
Dim token_type As String = json.StringOf("token_type")
Dim client_id As String = json.StringOf("client_id")
Dim i As Integer = 0
Dim count_i As Integer = json.SizeOfArray("keys")
While i < count_i
json.I = i
kty = json.StringOf("keys[i].kty")
n = json.StringOf("keys[i].n")
e = json.StringOf("keys[i].e")
use = json.StringOf("keys[i].use")
alg = json.StringOf("keys[i].alg")
x5t = json.StringOf("keys[i].x5t")
i = i + 1
End While
' This example will save the JSON containing the access key to a file so that
' a subsequent example can load it and then use the access key for a request, such as to create a payment request.
json.WriteFile("qa_data/tokens/ing_access_token.json")