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VB.NET

USPS OAuth2 Client Credentials

See more OAuth2 Examples

Get an OAuth2 access token for the United States Postal Service (USPS) REST API.

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

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

Dim http As New Chilkat.Http

' Implements the following CURL command:

' curl -X POST https://apis.usps.com/oauth2/v3/token \
'   -H "Content-Type: application/x-www-form-urlencoded" \
'   -d "grant_type=client_credentials" \
'   -d "client_id=123456789" \
'   -d "client_secret=A1B2C3D4E5" \
'   -d "scope=ResourceA+ResourceB+ResourceC"

' 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 Chilkat.HttpRequest
req.AddParam("grant_type","client_credentials")
req.AddParam("client_id","123456789")
req.AddParam("client_secret","A1B2C3D4E5")
req.AddParam("scope","ResourceA+ResourceB+ResourceC")

req.HttpVerb = "POST"
req.ContentType = "application/x-www-form-urlencoded"

Dim resp As New Chilkat.HttpResponse
success = http.HttpReq("https://apis.usps.com/oauth2/v3/token",req,resp)
If (success = False) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If


Dim sbResponseBody As New Chilkat.StringBuilder
resp.GetBodySb(sbResponseBody)

Dim jResp As New Chilkat.JsonObject
jResp.LoadSb(sbResponseBody)
jResp.EmitCompact = False

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

Dim respStatusCode As Integer = resp.StatusCode
Debug.WriteLine("Response Status Code = " & respStatusCode)
If (respStatusCode >= 400) Then
    Debug.WriteLine("Response Header:")
    Debug.WriteLine(resp.Header)
    Debug.WriteLine("Failed.")
    Exit Sub
End If


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

' {
'   "access_token": "eyJraWQiOiIxMDEwMTAiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJzdWIiOiIiLCJhdWQiOiJhZGRyZXNzZXMgaW50ZXJuYXRpb25hbC1wcmljZXMgc3Vic2NyaXB0aW9ucyBwYXltZW50cyBwaWNrdXAgdHJhY2tpbmcgbGFiZWxzIHNjYW4tZm9ybXMgY29tcGFuaWVzIHNlcnZpY2UtZGVsaXZlcnktc3RhbmRhcmRzIGxvY2F0aW9ucyBpbnRlcm5hdGlvbmFsLWxhYmVscyBwcmljZXMiLCJhenAiOiJoeXI3YjN2Q1J0cFl0QUhNMWE4Y2RVcmt5eUZtTmtiZyIsIm9yZ2FuaXphdGlvbl9pZCI6IjAiLCJpc3MiOiJ1cm46XC9cL2FwaS51c3BzLmNvbSIsImV4cCI6MTY4MDkxNzc4NiwiaWF0IjoxNjgwODg4OTg2LCJqdGkiOiI3YjU5MzJlMS05NjIxLTQzZDAtYTMyNy0xMzIxYWVjNzJjZGYifQ.QzrUxlT2rG4jvYbMDGnk23j8ZYfHJcdXPKR9CbSmcKeVpURaHhEMpPB6K4x5ut3xxeEGSzeE5VRz8vixI4iqyHsD8rSdkLTPHy0iovUHOZQBAJVQ6hii9jpLhxUXmiTtH3jKzSj_f2fuNmZbIGhf-CR2FBeWF-aBPzEDEMV95nkCUMfW_Z2BmkbraSfvQZxkCO-cLrMAwlYcrzUtaJ7vnazeQB4sep5BBHBEvsa4kfq6_tz6BAKgv3R7cI2NkSv-wgy_IGoTjVCMTS8mJHGs_t8cWCO8-z4lxW1tUwIBKOCUDpmEEnGgiG6Sl0C_gGl4bZ5cDSl4IgPpcOVi9jZ7LA",
'   "token_type": "Bearer",
'   "issued_at": 1680888985929,
'   "expires_in": 28799,
'   "status": "approved",
'   "scope": "addresses international-prices subscriptions payments pickup tracking labels scan-forms companies service-delivery-standards locations international-labels prices",
'   "issuer": "api.usps.com",
'   "client_id": "hyr7b3vCRtpYtAHM1a8cdUrkyyFmNkbg",
'   "application_name": "Silver Shipper Developer",
'   "api_products": "[Shipping-Silver]",
'   "public_key": "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"
' }

' 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 = jResp.StringOf("access_token")
Dim token_type As String = jResp.StringOf("token_type")
Dim issued_at As Integer = jResp.IntOf("issued_at")
Dim expires_in As Integer = jResp.IntOf("expires_in")
Dim status As String = jResp.StringOf("status")
Dim scope As String = jResp.StringOf("scope")
Dim issuer As String = jResp.StringOf("issuer")
Dim client_id As String = jResp.StringOf("client_id")
Dim application_name As String = jResp.StringOf("application_name")
Dim api_products As String = jResp.StringOf("api_products")
Dim public_key As String = jResp.StringOf("public_key")