(PowerBuilder) ING Open Banking OAuth2 Client Credentials

Demonstrates how to get an access token for the ING Open Banking APIs using client credentials.

For more information, see https://developer.ing.com/openbanking/get-started/openbanking

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
oleobject loo_Cert
integer li_Success
oleobject loo_BdPrivKey
oleobject loo_PrivKey
oleobject loo_Http
oleobject loo_Crypt
string ls_Payload
string ls_PayloadDigest
oleobject loo_Dt
string ls_HttpMethod
string ls_ReqPath
oleobject loo_SbStringToSign
oleobject loo_SigningPrivKey
oleobject loo_Rsa
string ls_B64Signature
oleobject loo_SbAuthHdrVal
oleobject loo_SbDigestHdrVal
oleobject loo_Req
oleobject loo_Resp
oleobject loo_Json
string ls_Kty
string n
string e
string ls_Use
string ls_Alg
string ls_X5t
string ls_Access_token
integer li_Expires_in
string ls_Scope
string ls_Token_type
string ls_Client_id
integer i
integer li_Count_i

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

loo_Cert = create oleobject
// Use "Chilkat_9_5_0.Cert" for versions of Chilkat < 10.0.0
li_rc = loo_Cert.ConnectToNewObject("Chilkat.Cert")
if li_rc < 0 then
    destroy loo_Cert
    MessageBox("Error","Connecting to COM object failed")
    return
end if
li_Success = loo_Cert.LoadFromFile("qa_data/certs_and_keys/ING/example_client_tls.cer")
if li_Success = 0 then
    Write-Debug loo_Cert.LastErrorText
    destroy loo_Cert
    return
end if

loo_BdPrivKey = create oleobject
// Use "Chilkat_9_5_0.BinData" for versions of Chilkat < 10.0.0
li_rc = loo_BdPrivKey.ConnectToNewObject("Chilkat.BinData")

li_Success = loo_BdPrivKey.LoadFile("qa_data/certs_and_keys/ING/example_client_tls.key")
if li_Success = 0 then
    Write-Debug "Failed to load example_client_tls.key"
    destroy loo_Cert
    destroy loo_BdPrivKey
    return
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.

loo_PrivKey = create oleobject
// Use "Chilkat_9_5_0.PrivateKey" for versions of Chilkat < 10.0.0
li_rc = loo_PrivKey.ConnectToNewObject("Chilkat.PrivateKey")

li_Success = loo_PrivKey.LoadAnyFormat(loo_BdPrivKey,"")
if li_Success = 0 then
    Write-Debug loo_PrivKey.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    return
end if

// Associate the private key with the certificate.
li_Success = loo_Cert.SetPrivateKey(loo_PrivKey)
if li_Success = 0 then
    Write-Debug loo_Cert.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    return
end if

loo_Http = create oleobject
// Use "Chilkat_9_5_0.Http" for versions of Chilkat < 10.0.0
li_rc = loo_Http.ConnectToNewObject("Chilkat.Http")

li_Success = loo_Http.SetSslClientCert(loo_Cert)
if li_Success = 0 then
    Write-Debug loo_Http.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    destroy loo_Http
    return
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
loo_Crypt = create oleobject
// Use "Chilkat_9_5_0.Crypt2" for versions of Chilkat < 10.0.0
li_rc = loo_Crypt.ConnectToNewObject("Chilkat.Crypt2")

loo_Crypt.HashAlgorithm = "SHA256"
loo_Crypt.EncodingMode = "base64"
ls_Payload = "grant_type=client_credentials"
ls_PayloadDigest = loo_Crypt.HashStringENC(ls_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")  
loo_Dt = create oleobject
// Use "Chilkat_9_5_0.CkDateTime" for versions of Chilkat < 10.0.0
li_rc = loo_Dt.ConnectToNewObject("Chilkat.CkDateTime")

loo_Dt.SetFromCurrentSystemTime()
// The desire date/time format is the "RFC822" format.
loo_Http.SetRequestHeader("Date",loo_Dt.GetAsRfc822(0))

// 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`

ls_HttpMethod = "POST"
ls_ReqPath = "/oauth2/token"

loo_SbStringToSign = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_SbStringToSign.ConnectToNewObject("Chilkat.StringBuilder")

loo_SbStringToSign.Append("(request-target): ")
loo_SbStringToSign.Append(ls_HttpMethod)
loo_SbStringToSign.ToLowercase()
loo_SbStringToSign.Append(" ")
loo_SbStringToSign.AppendLine(ls_ReqPath,0)

loo_SbStringToSign.Append("date: ")
loo_SbStringToSign.AppendLine(loo_Dt.GetAsRfc822(0),0)

loo_SbStringToSign.Append("digest: SHA-256=")
loo_SbStringToSign.Append(ls_PayloadDigest)

loo_SigningPrivKey = create oleobject
// Use "Chilkat_9_5_0.PrivateKey" for versions of Chilkat < 10.0.0
li_rc = loo_SigningPrivKey.ConnectToNewObject("Chilkat.PrivateKey")

li_Success = loo_SigningPrivKey.LoadPemFile("qa_data/certs_and_keys/ING/example_client_signing.key")
if li_Success = 0 then
    Write-Debug loo_SigningPrivKey.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    destroy loo_Http
    destroy loo_Crypt
    destroy loo_Dt
    destroy loo_SbStringToSign
    destroy loo_SigningPrivKey
    return
end if

loo_Rsa = create oleobject
// Use "Chilkat_9_5_0.Rsa" for versions of Chilkat < 10.0.0
li_rc = loo_Rsa.ConnectToNewObject("Chilkat.Rsa")

li_Success = loo_Rsa.ImportPrivateKeyObj(loo_SigningPrivKey)
if li_Success = 0 then
    Write-Debug loo_Rsa.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    destroy loo_Http
    destroy loo_Crypt
    destroy loo_Dt
    destroy loo_SbStringToSign
    destroy loo_SigningPrivKey
    destroy loo_Rsa
    return
end if

loo_Rsa.EncodingMode = "base64"
ls_B64Signature = loo_Rsa.SignStringENC(loo_SbStringToSign.GetAsString(),"SHA256")

loo_SbAuthHdrVal = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_SbAuthHdrVal.ConnectToNewObject("Chilkat.StringBuilder")

loo_SbAuthHdrVal.Append("Signature keyId=~"e77d776b-90af-4684-bebc-521e5b2614dd~",")
loo_SbAuthHdrVal.Append("algorithm=~"rsa-sha256~",")
loo_SbAuthHdrVal.Append("headers=~"(request-target) date digest~",")
loo_SbAuthHdrVal.Append("signature=~"")
loo_SbAuthHdrVal.Append(ls_B64Signature)
loo_SbAuthHdrVal.Append("~"")

loo_SbDigestHdrVal = create oleobject
// Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
li_rc = loo_SbDigestHdrVal.ConnectToNewObject("Chilkat.StringBuilder")

loo_SbDigestHdrVal.Append("SHA-256=")
loo_SbDigestHdrVal.Append(ls_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"

loo_Req = create oleobject
// Use "Chilkat_9_5_0.HttpRequest" for versions of Chilkat < 10.0.0
li_rc = loo_Req.ConnectToNewObject("Chilkat.HttpRequest")

loo_Req.AddParam("grant_type","client_credentials")
loo_Req.AddHeader("Accept","application/json")
loo_Req.AddHeader("Date",loo_Dt.GetAsRfc822(0))
loo_Req.AddHeader("Digest",loo_SbDigestHdrVal.GetAsString())
loo_Req.AddHeader("Authorization",loo_SbAuthHdrVal.GetAsString())
loo_Resp = loo_Http.PostUrlEncoded("https://api.sandbox.ing.com/oauth2/token",loo_Req)
if loo_Http.LastMethodSuccess = 0 then
    Write-Debug loo_Http.LastErrorText
    destroy loo_Cert
    destroy loo_BdPrivKey
    destroy loo_PrivKey
    destroy loo_Http
    destroy loo_Crypt
    destroy loo_Dt
    destroy loo_SbStringToSign
    destroy loo_SigningPrivKey
    destroy loo_Rsa
    destroy loo_SbAuthHdrVal
    destroy loo_SbDigestHdrVal
    destroy loo_Req
    return
end if

// If successful, the status code = 200
Write-Debug "Response Status Code: " + string(loo_Resp.StatusCode)
Write-Debug loo_Resp.BodyStr

loo_Json = create oleobject
// Use "Chilkat_9_5_0.JsonObject" for versions of Chilkat < 10.0.0
li_rc = loo_Json.ConnectToNewObject("Chilkat.JsonObject")

loo_Json.Load(loo_Resp.BodyStr)

destroy loo_Resp

loo_Json.EmitCompact = 0
Write-Debug loo_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

ls_Access_token = loo_Json.StringOf("access_token")
li_Expires_in = loo_Json.IntOf("expires_in")
ls_Scope = loo_Json.StringOf("scope")
ls_Token_type = loo_Json.StringOf("token_type")
ls_Client_id = loo_Json.StringOf("client_id")
i = 0
li_Count_i = loo_Json.SizeOfArray("keys")
do while i < li_Count_i
    loo_Json.I = i
    ls_Kty = loo_Json.StringOf("keys[i].kty")
    n = loo_Json.StringOf("keys[i].n")
    e = loo_Json.StringOf("keys[i].e")
    ls_Use = loo_Json.StringOf("keys[i].use")
    ls_Alg = loo_Json.StringOf("keys[i].alg")
    ls_X5t = loo_Json.StringOf("keys[i].x5t")
    i = i + 1
loop

// 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.
loo_Json.WriteFile("qa_data/tokens/ing_access_token.json")


destroy loo_Cert
destroy loo_BdPrivKey
destroy loo_PrivKey
destroy loo_Http
destroy loo_Crypt
destroy loo_Dt
destroy loo_SbStringToSign
destroy loo_SigningPrivKey
destroy loo_Rsa
destroy loo_SbAuthHdrVal
destroy loo_SbDigestHdrVal
destroy loo_Req
destroy loo_Json