(PureBasic) PayPal - Generate Invoice Number

Generates the next invoice number that is available to the user.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkRest.pb"

Procedure ChilkatExample()

    ; Note: Requires Chilkat v9.5.0.65 or greater.

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

    ; Load our previously obtained access token. (see PayPal OAuth2 Access Token)
    jsonToken.i = CkJsonObject::ckCreate()
    If jsonToken.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoadFile(jsonToken,"qa_data/tokens/paypal.json")

    ; Build the Authorization request header field value.
    sbAuth.i = CkStringBuilder::ckCreate()
    If sbAuth.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; token_type should be "Bearer"
    CkStringBuilder::ckAppend(sbAuth,CkJsonObject::ckStringOf(jsonToken,"token_type"))
    CkStringBuilder::ckAppend(sbAuth," ")
    CkStringBuilder::ckAppend(sbAuth,CkJsonObject::ckStringOf(jsonToken,"access_token"))

    ; Make the initial connection.
    ; A single REST object, once connected, can be used for many PayPal REST API calls.
    ; The auto-reconnect indicates that if the already-established HTTPS connection is closed,
    ; then it will be automatically re-established as needed.
    rest.i = CkRest::ckCreate()
    If rest.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    bAutoReconnect.i = 1
    success.i = CkRest::ckConnect(rest,"api.sandbox.paypal.com",443,1,bAutoReconnect)
    If success <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkJsonObject::ckDispose(jsonToken)
        CkStringBuilder::ckDispose(sbAuth)
        CkRest::ckDispose(rest)
        ProcedureReturn
    EndIf

    ; ----------------------------------------------------------------------------------------------
    ; The code above this comment could be placed inside a function/subroutine within the application
    ; because the connection does not need to be made for every request.  Once the connection is made
    ; the app may send many requests..
    ; ----------------------------------------------------------------------------------------------

    ; Clear the REST object of any headers or query params from previous requests.
    CkRest::ckClearAllHeaders(rest)
    CkRest::ckClearAllQueryParams(rest)

    CkRest::ckAddHeader(rest,"Authorization",CkStringBuilder::ckGetAsString(sbAuth))

    ; Send the POST request with an emtpy body and get the JSON response.
    sbJsonRequest.i = CkStringBuilder::ckCreate()
    If sbJsonRequest.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

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

    success = CkRest::ckFullRequestSb(rest,"POST","/v1/invoicing/invoices/next-invoice-number",sbJsonRequest,sbJsonResponse)
    If success <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkJsonObject::ckDispose(jsonToken)
        CkStringBuilder::ckDispose(sbAuth)
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbJsonRequest)
        CkStringBuilder::ckDispose(sbJsonResponse)
        ProcedureReturn
    EndIf

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

    CkJsonObject::setCkEmitCompact(json, 0)
    CkJsonObject::ckLoadSb(json,sbJsonResponse)

    Debug "Response Status Code = " + Str(CkRest::ckResponseStatusCode(rest))

    ; Did we get a 200 success response?
    If CkRest::ckResponseStatusCode(rest) <> 200
        Debug CkJsonObject::ckEmit(json)
        Debug "Failed."
        CkJsonObject::ckDispose(jsonToken)
        CkStringBuilder::ckDispose(sbAuth)
        CkRest::ckDispose(rest)
        CkStringBuilder::ckDispose(sbJsonRequest)
        CkStringBuilder::ckDispose(sbJsonResponse)
        CkJsonObject::ckDispose(json)
        ProcedureReturn
    EndIf

    ; Sample JSON response is shown below.
    Debug CkJsonObject::ckEmit(json)
    Debug "----------------------"
    Debug "Next invoice number: " + CkJsonObject::ckStringOf(json,"number")
    Debug "success"

    ; ------------------------------------------------
    ; A sample JSON response:

    ; 	{ 
    ; 	  "number": "0003"
    ; 	}


    CkJsonObject::ckDispose(jsonToken)
    CkStringBuilder::ckDispose(sbAuth)
    CkRest::ckDispose(rest)
    CkStringBuilder::ckDispose(sbJsonRequest)
    CkStringBuilder::ckDispose(sbJsonResponse)
    CkJsonObject::ckDispose(json)


    ProcedureReturn
EndProcedure