(PureBasic) RSAP Union API - Get OAuth2 Access Token

Demonstrates how to get an OAuth2 access token for the RSAP Union API. Note: This uses the client credentials flow, which does NOT require an interactive engagement using a browser.

For more information, see https://app.swaggerhub.com/apis-docs/pderas/RSAP/2.0.1#/Authentication/getOauthToken

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkJsonObject.pb"
IncludeFile "CkPrivateKey.pb"
IncludeFile "CkHttp.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkHttpResponse.pb"
IncludeFile "CkCert.pb"

Procedure ChilkatExample()

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

    http.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success.i

    ; The following JSON is sent in the request body.

    ; {
    ;   "grant_type": "client_credentials",
    ;   "client_id": 1234,
    ;   "client_secret": "23456abcde"
    ; }

    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckUpdateString(json,"grant_type","client_credentials")
    CkJsonObject::ckUpdateInt(json,"client_id",1234)
    CkJsonObject::ckUpdateString(json,"client_secret","23456abcde")

    CkHttp::ckSetRequestHeader(http,"Content-type","application/json")

    ; Add the client certificate TLS authentication.
    cert.i = CkCert::ckCreate()
    If cert.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkCert::ckLoadFromFile(cert,"qa_data/certs_and_keys/union_client_certificate.crt")
    If success = 0
        Debug CkCert::ckLastErrorText(cert)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    privKey.i = CkPrivateKey::ckCreate()
    If privKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPrivateKey::ckLoadAnyFormatFile(privKey,"qa_data/certs_and_keys/union_client_certificate.nopass.key","")
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; Associate the private key with the cert.
    ; This will fail if the private key is not actually the correct one that corresponds to the public key stored within the cert.
    success = CkCert::ckSetPrivateKey(cert,privKey)
    If success = 0
        Debug CkCert::ckLastErrorText(cert)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; Tell HTTP to use the cert for client TLS certificate authentication.
    success = CkHttp::ckSetSslClientCert(http,cert)
    If success = 0
        Debug CkHttp::ckLastErrorText(http)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    resp.i = CkHttp::ckPostJson3(http,"https://api-test.rsap.ca/oauth/token","application/json",json)
    If CkHttp::ckLastMethodSuccess(http) = 0
        Debug CkHttp::ckLastErrorText(http)
        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    sbResponseBody.i = CkStringBuilder::ckCreate()
    If sbResponseBody.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttpResponse::ckGetBodySb(resp,sbResponseBody)
    jResp.i = CkJsonObject::ckCreate()
    If jResp.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoadSb(jResp,sbResponseBody)
    CkJsonObject::setCkEmitCompact(jResp, 0)

    Debug "Response Body:"
    Debug CkJsonObject::ckEmit(jResp)

    respStatusCode.i = CkHttpResponse::ckStatusCode(resp)
    Debug "Response Status Code = " + Str(respStatusCode)
    If respStatusCode >= 400
        Debug "Response Header:"
        Debug CkHttpResponse::ckHeader(resp)
        Debug "Failed."
        CkHttpResponse::ckDispose(resp)

        CkHttp::ckDispose(http)
        CkJsonObject::ckDispose(json)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        CkStringBuilder::ckDispose(sbResponseBody)
        CkJsonObject::ckDispose(jResp)
        ProcedureReturn
    EndIf

    CkHttpResponse::ckDispose(resp)

    ; Sample JSON response:
    ; (Sample code for parsing the JSON response is shown below)

    ; {
    ;   "token_type": "Bearer",
    ;   "expires_in": 3600,
    ;   "access_token": "eyJ0eXAi...LnE"
    ; }

    ; This token expires in 1 hour.  Your application could re-use the same token for up to an hour,
    ; or it can simply get a new access token before each request (if you're not doing too many requests).
    success = CkJsonObject::ckWriteFile(jResp,"qa_data/tokens/rsapToken.json")


    CkHttp::ckDispose(http)
    CkJsonObject::ckDispose(json)
    CkCert::ckDispose(cert)
    CkPrivateKey::ckDispose(privKey)
    CkStringBuilder::ckDispose(sbResponseBody)
    CkJsonObject::ckDispose(jResp)


    ProcedureReturn
EndProcedure