(Visual Basic 6.0) Get Ebay OAuth2 Token using Client Credentials Grant Flow

See more eBay Examples

Demonstrates how to get a Ebay OAuth2 access token using the client credentials grant flow.

There are two ways of "minting" an OAuth2 access token.

1. The authorization code grant flow (https://developer.ebay.com/api-docs/static/oauth-authorization-code-grant.html) This is where your app will be accessing another person's eBay account. It's an interactive process and requires the account owner's permission to get the access token the 1st time. After that, it can be refreshed indefinitely without user interaction.
2. The client credentials grant flow (this example) (https://developer.ebay.com/api-docs/static/oauth-client-credentials-grant.html) This is where you access your own eBay account. It's non-interactive and you can do it in automated services where user-interaction is not possible.

For more information, see https://developer.ebay.com/api-docs/static/oauth-client-credentials-grant.html

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

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

Dim http As New ChilkatHttp
Dim success As Long

' Implements the following CURL command:

' curl -X POST 'https://api.sandbox.ebay.com/identity/v1/oauth2/token' \
'   -H 'Content-Type: application/x-www-form-urlencoded' \
'   -H 'Authorization: Basic UkVTVFRlc3...wZi1hOGZhLTI4MmY=' \
'   -d 'grant_type=client_credentials&scope=https%3A%2F%2Fapi.ebay.com%2Foauth%2Fapi_scope'

' Use the following online tool to generate HTTP code from a CURL command
' Convert a cURL Command to HTTP Source Code

Dim req As New ChilkatHttpRequest
req.HttpVerb = "POST"
req.Path = "/identity/v1/oauth2/token"
req.ContentType = "application/x-www-form-urlencoded"
req.AddParam "grant_type","client_credentials"

' The scope query param indicates the access to be provided by the token.
' Multiple scopes can be specified by separating each with a SPACE char.
' See the Ebay OAuth scopes documentation

Dim scope As String
scope = "https://api.ebay.com/oauth/api_scope https://api.ebay.com/oauth/api_scope/buy.order.readonly https://api.ebay.com/oauth/api_scope/buy.guest.order https://api.ebay.com/oauth/api_scope/sell.marketing.readonly https://api.ebay.com/oauth/api_scope/sell.marketing https://api.ebay.com/oauth/api_scope/sell.inventory.readonly https://api.ebay.com/oauth/api_scope/sell.inventory https://api.ebay.com/oauth/api_scope/sell.account.readonly https://api.ebay.com/oauth/api_scope/sell.account https://api.ebay.com/oauth/api_scope/sell.fulfillment.readonly https://api.ebay.com/oauth/api_scope/sell.fulfillment https://api.ebay.com/oauth/api_scope/sell.analytics.readonly https://api.ebay.com/oauth/api_scope/sell.marketplace.insights.readonly https://api.ebay.com/oauth/api_scope/commerce.catalog.readonly https://api.ebay.com/oauth/api_scope/buy.shopping.cart https://api.ebay.com/oauth/api_scope/buy.offer.auction"

req.AddParam "scope",scope

' Setting these properties causes the Authorization: Basic UkVTVFRlc3...wZi1hOGZhLTI4MmY=
' header to be added.
http.Login = "EBAY_CLIENT_ID"
http.Password = "EBAY_CLIENT_SECRET"
http.BasicAuth = 1

Dim resp As ChilkatHttpResponse
Set resp = http.PostUrlEncoded("https://api.sandbox.ebay.com/identity/v1/oauth2/token",req)
If (http.LastMethodSuccess = 0) Then
    Debug.Print http.LastErrorText
    Exit Sub
End If

Dim sbResponseBody As New ChilkatStringBuilder
success = resp.GetBodySb(sbResponseBody)
Dim jResp As New ChilkatJsonObject
success = jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = 0

Debug.Print "Response Body:"
Debug.Print jResp.Emit()

Dim respStatusCode As Long
respStatusCode = resp.StatusCode
Debug.Print "Response Status Code = " & respStatusCode
If (respStatusCode >= 400) Then
    Debug.Print "Response Header:"
    Debug.Print resp.Header
    Debug.Print "Failed."

    Exit Sub
End If

' Sample JSON response:
' (Sample code for parsing the JSON response is shown below)

' {
'   "access_token": "v^1.1#i^1#p^1#r^0#I^3#f^0#t^H4s ... wu67e3xAhskz4DAAA",
'   "expires_in": 7200,
'   "token_type": "Application Access Token"
' }

' Sample code for parsing the JSON response...
' Use the following online tool to generate parsing code from sample JSON:
' Generate Parsing Code from JSON

Dim access_token As String
access_token = jResp.StringOf("access_token")
Dim expires_in As Long
expires_in = jResp.IntOf("expires_in")
Dim token_type As String
token_type = jResp.StringOf("token_type")