(Xojo Plugin) 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 Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim http As New Chilkat.Http

Dim jsonToken As New Chilkat.JsonObject
Dim success As Boolean
success = jsonToken.LoadFile("qa_data/tokens/xero-access-token.json")
If (success = False) Then
    System.DebugLog(jsonToken.LastErrorText)
    Return
End If

http.AuthToken = jsonToken.StringOf("access_token")

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

http.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
//     }
//   ]
// }

Dim url As String
url = "https://api.xero.com/api.xro/2.0/{$Endpoint}/{$Guid}/Attachments/{$AttachmentId}"

// Endpoint can be Invoices, Receipts, CreditNotes, PurchaseOrders, etc.
success = http.SetUrlVar("Endpoint","Invoices")

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

// AttachmentId is the ID of the particular attachment to be downloaded
success = http.SetUrlVar("AttachmentId","daf106e2-8634-4349-bfcc-86c1df0793b2")

// Download the attachment data into bd.
Dim bd As New Chilkat.BinData
success = http.QuickGetBd(url,bd)
If (success = False) Then
    System.DebugLog(http.LastErrorText)
    Return
End If

System.DebugLog("Response Status Code: " + Str(http.LastStatus))

If (http.LastStatus = 200) Then
    // Success
    // Save to a file..
    success = bd.WriteFile("qa_output/penguines.jpg")
Else
    // Failed.  bd contains error information..
    System.DebugLog(bd.GetString("utf-8"))
End If