(Lianja) PayPal Generate QR Code

Generates a QR code for an invoice, by ID.

The QR code is a PNG image in Base64-encoded format that corresponds to the invoice ID.

Note: A QR code can only be generated for an invoice that has been both created and sent.

See also Generate QR Code

Chilkat Lianja Extension Download Chilkat Lianja Extension

// Note: Requires Chilkat v9.5.0.64 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)
loJsonToken = createobject("CkJsonObject")
loJsonToken.LoadFile("qa_data/tokens/paypal.json")

// Build the Authorization request header field value.
loSbAuth = createobject("CkStringBuilder")
// token_type should be "Bearer"
loSbAuth.Append(loJsonToken.StringOf("token_type"))
loSbAuth.Append(" ")
loSbAuth.Append(loJsonToken.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.
loRest = createobject("CkRest")
llBAutoReconnect = .T.
llSuccess = loRest.Connect("api.sandbox.paypal.com",443,.T.,llBAutoReconnect)
if (llSuccess <> .T.) then
    ? loRest.LastErrorText
    release loJsonToken
    release loSbAuth
    release loRest
    return
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..
// ----------------------------------------------------------------------------------------------

// Build a path using an invoice ID.
loSbPath = createobject("CkStringBuilder")
loSbPath.Append("/v1/invoicing/invoices/invoice_id/qr-code")
lnNumReplacements = loSbPath.Replace("invoice_id","INV2-ZG2H-HKAW-PMWU-N6ZR")

loRest.AddHeader("Authorization",loSbAuth.GetAsString())
// A 500x500 image results in a PNG file of approx. 4K bytes in size.
loRest.AddQueryParam("width","500")
loRest.AddQueryParam("height","500")
loRest.AddQueryParam("action","pay")

// Send the GET request and get the PNG image data as base64.
// A successful JSON response looks like this:
// {"image":"iVBORw0KGgoAA....AASUVORK5CYII="}
loSbJsonResponse = createobject("CkStringBuilder")
llSuccess = loRest.FullRequestNoBodySb("GET",loSbPath.GetAsString(),loSbJsonResponse)
if (llSuccess <> .T.) then
    ? loRest.LastErrorText
    release loJsonToken
    release loSbAuth
    release loRest
    release loSbPath
    release loSbJsonResponse
    return
endif

loJson = createobject("CkJsonObject")
loJson.EmitCompact = .F.
loJson.LoadSb(loSbJsonResponse)

? "Response Status Code = " + str(loRest.ResponseStatusCode)

// Did we get a 200 success response?
if (loRest.ResponseStatusCode <> 200) then
    ? loJson.Emit()
    ? "Failed."
    release loJsonToken
    release loSbAuth
    release loRest
    release loSbPath
    release loSbJsonResponse
    release loJson
    return
endif

// If the 200 response is received, the response body contains the PNG data.
// Save the PNG to a file.
loPngData = createobject("CkBinData")
loPngData.AppendEncoded(loJson.StringOf("image"),"base64")
llSuccess = loPngData.WriteFile("qa_output/paypal_qr_code.png")
if (llSuccess = .F.) then
    ? "Failed to save PNG file."
    release loJsonToken
    release loSbAuth
    release loRest
    release loSbPath
    release loSbJsonResponse
    release loJson
    release loPngData
    return
endif

? "Success."


release loJsonToken
release loSbAuth
release loRest
release loSbPath
release loSbJsonResponse
release loJson
release loPngData