(VB.NET) Debug REST HTTP Request

Demonstrates how to generate the HTTP Request (with all headers intact) without actually sending the request.

Note: This example requires Chilkat v9.5.0.77 or later.

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

' This example will connect to the web server, but does not actually send a request.
' When in DebugMode, the request is composed in memory and can be retrieved by calling
' GetLastDebugRequest.

Dim rest As New Chilkat.Rest

' Connect Code...
' URL: https://test-api.service.hmrc.gov.uk/organisations/vat/MY_HMRC_VRN/returns
Dim bTls As Boolean = True
Dim port As Integer = 443
Dim bAutoReconnect As Boolean = True
Dim success As Boolean = rest.Connect("test-api.service.hmrc.gov.uk",port,bTls,bAutoReconnect)
If (success <> True) Then
    Debug.WriteLine("ConnectFailReason: " & rest.ConnectFailReason)
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


' Build the request body...
Dim json As New Chilkat.JsonObject
json.UpdateString("periodKey","A001")
json.UpdateNumber("vatDueSales","105.50")
json.UpdateNumber("vatDueAcquisitions","-100.45")
json.UpdateNumber("totalVatDue","5.05")
json.UpdateNumber("vatReclaimedCurrPeriod","105.15")
json.UpdateNumber("netVatDue","100.10")
json.UpdateInt("totalValueSalesExVAT",300)
json.UpdateInt("totalValuePurchasesExVAT",300)
json.UpdateInt("totalValueGoodsSuppliedExVAT",3000)
json.UpdateInt("totalAcquisitionsExVAT",3000)
json.UpdateBool("finalised",True)

' Add Headers...
rest.AddHeader("Accept","application/vnd.hmrc.1.0+json")
rest.AddHeader("Authorization","Bearer HMRC_ACCESS_TOKEN")
rest.AddHeader("Content-Type","application/json")


Dim sbRequestBody As New Chilkat.StringBuilder
json.EmitSb(sbRequestBody)

' Set DebugMode so that no request is actually sent.
rest.DebugMode = True

Dim sbResponseBody As New Chilkat.StringBuilder
success = rest.FullRequestSb("POST","/organisations/vat/MY_HMRC_VRN/returns",sbRequestBody,sbResponseBody)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


' Get the exact contents of what would've been sent.
' This includes the HTTP start line, the HTTP request headers, and the request body.
' Given that it's possible for the request body to contain binary data,
' the GetLastDebugRequest fetches into a BinData object.
' In this case, however, our request body contained JSON, so we can
' examine it as a string..
Dim bdRequest As New Chilkat.BinData
success = rest.GetLastDebugRequest(bdRequest)

Debug.WriteLine("----")
Debug.WriteLine(bdRequest.GetString("utf-8"))
Debug.WriteLine("----")

' The output for the above case:

' POST /organisations/vat/MY_HMRC_VRN/returns HTTP/1.1
' Accept: application/vnd.hmrc.1.0+json
' Host: test-api.service.hmrc.gov.uk
' Authorization: Bearer HMRC_ACCESS_TOKEN
' Content-Type: application/json
' Content-Length: 281
' 
' {"periodKey":"A001","vatDueSales":105.50, ... ,"finalised":true}
' 
'