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PayPal - Generate Invoice Number

See more PayPal Examples

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

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

Chilkat Go Downloads

Go
    success := false

    // 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 := chilkat.NewJsonObject()
    jsonToken.LoadFile("qa_data/tokens/paypal.json")

    // Build the Authorization request header field value.
    sbAuth := chilkat.NewStringBuilder()
    // token_type should be "Bearer"
    sbAuth.Append(*jsonToken.StringOf("token_type"))
    sbAuth.Append(" ")
    sbAuth.Append(*jsonToken.StringOf("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 := chilkat.NewRest()
    bAutoReconnect := true
    success = rest.Connect("api.sandbox.paypal.com",443,true,bAutoReconnect)
    if success != true {
        fmt.Println(rest.LastErrorText())
        jsonToken.DisposeJsonObject()
        sbAuth.DisposeStringBuilder()
        rest.DisposeRest()
        return
    }

    // ----------------------------------------------------------------------------------------------
    // 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.
    rest.ClearAllHeaders()
    rest.ClearAllQueryParams()

    rest.AddHeader("Authorization",*sbAuth.GetAsString())

    // Send the POST request with an emtpy body and get the JSON response.
    sbJsonRequest := chilkat.NewStringBuilder()
    sbJsonResponse := chilkat.NewStringBuilder()
    success = rest.FullRequestSb("POST","/v1/invoicing/invoices/next-invoice-number",sbJsonRequest,sbJsonResponse)
    if success != true {
        fmt.Println(rest.LastErrorText())
        jsonToken.DisposeJsonObject()
        sbAuth.DisposeStringBuilder()
        rest.DisposeRest()
        sbJsonRequest.DisposeStringBuilder()
        sbJsonResponse.DisposeStringBuilder()
        return
    }

    json := chilkat.NewJsonObject()
    json.SetEmitCompact(false)
    json.LoadSb(sbJsonResponse)

    fmt.Println("Response Status Code = ", rest.ResponseStatusCode())

    // Did we get a 200 success response?
    if rest.ResponseStatusCode() != 200 {
        fmt.Println(*json.Emit())
        fmt.Println("Failed.")
        jsonToken.DisposeJsonObject()
        sbAuth.DisposeStringBuilder()
        rest.DisposeRest()
        sbJsonRequest.DisposeStringBuilder()
        sbJsonResponse.DisposeStringBuilder()
        json.DisposeJsonObject()
        return
    }

    // Sample JSON response is shown below.
    fmt.Println(*json.Emit())
    fmt.Println("----------------------")
    fmt.Println("Next invoice number: ", *json.StringOf("number"))
    fmt.Println("success")

    // ------------------------------------------------
    // A sample JSON response:

    // 	{ 
    // 	  "number": "0003"
    // 	}

    jsonToken.DisposeJsonObject()
    sbAuth.DisposeStringBuilder()
    rest.DisposeRest()
    sbJsonRequest.DisposeStringBuilder()
    sbJsonResponse.DisposeStringBuilder()
    json.DisposeJsonObject()