(Visual FoxPro) Xero Download Attachment for an Item (such as an Invoice)

Demonstrates how to download a particular attachment for a particular Xero item.

For more information, see https://developer.xero.com/documentation/api/attachments#GET

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

LOCAL loHttp
LOCAL loJsonToken
LOCAL lnSuccess
LOCAL lcUrl
LOCAL loBd

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

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Http')
loHttp = CreateObject('Chilkat.Http')

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJsonToken = CreateObject('Chilkat.JsonObject')
lnSuccess = loJsonToken.LoadFile("qa_data/tokens/xero-access-token.json")
IF (lnSuccess = 0) THEN
    ? loJsonToken.LastErrorText
    RELEASE loHttp
    RELEASE loJsonToken
    CANCEL
ENDIF

loHttp.AuthToken = loJsonToken.StringOf("access_token")

* Replace the value here with an actual tenant ID obtained from this example:
* Get Xero Tenant IDs
loHttp.SetRequestHeader("Xero-tenant-id","83299b9e-5747-4a14-a18a-a6c94f824eb7")

loHttp.Accept = "application/json"

* The example to list Xero attachments shows how to get attachment information.
* Here's a sample JSON response obtained form listing attachments:
* Your application can get the AttachmentID's and filenames from it.

* {
*   "Id": "24bfbcb9-dec9-4d33-835c-8f165d776766",
*   "Status": "OK",
*   "ProviderName": "Chilkat2222",
*   "DateTimeUTC": "\/Date(1587213296972)\/",
*   "Attachments": [
*     {
*       "AttachmentID": "daf106e2-8634-4349-bfcc-86c1df0793b2",
*       "FileName": "penguins.jpg",
*       "Url": "https://api.xero.com/api.xro/2.0/Invoices/0032f627-3156-4d30-9b1c-4d3b994dc921/Attachments/penguins.jpg",
*       "MimeType": "image/jpg",
*       "ContentLength": 777835
*     }
*   ]
* }

lcUrl = "https://api.xero.com/api.xro/2.0/{$Endpoint}/{$Guid}/Attachments/{$AttachmentId}"

* Endpoint can be Invoices, Receipts, CreditNotes, PurchaseOrders, etc.
loHttp.SetUrlVar("Endpoint","Invoices")

* Guid is the ID of the item, such as the InvoiceID.
loHttp.SetUrlVar("Guid","0032f627-3156-4d30-9b1c-4d3b994dc921")

* AttachmentId is the ID of the particular attachment to be downloaded
loHttp.SetUrlVar("AttachmentId","daf106e2-8634-4349-bfcc-86c1df0793b2")

* Download the attachment data into bd.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.BinData')
loBd = CreateObject('Chilkat.BinData')
lnSuccess = loHttp.QuickGetBd(lcUrl,loBd)
IF (lnSuccess = 0) THEN
    ? loHttp.LastErrorText
    RELEASE loHttp
    RELEASE loJsonToken
    RELEASE loBd
    CANCEL
ENDIF

? "Response Status Code: " + STR(loHttp.LastStatus)

IF (loHttp.LastStatus = 200) THEN
    * Success
    * Save to a file..
    lnSuccess = loBd.WriteFile("qa_output/penguines.jpg")
ELSE
    * Failed.  bd contains error information..
    ? loBd.GetString("utf-8")
ENDIF

RELEASE loHttp
RELEASE loJsonToken
RELEASE loBd