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Xbase++

USPS OAuth2 Client Credentials

See more OAuth2 Examples

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

Chilkat Xbase++ Downloads

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Xbase++ 
LOCAL nSuccess
LOCAL oHttp
LOCAL oReq
LOCAL oResp
LOCAL oSbResponseBody
LOCAL oJResp
LOCAL nRespStatusCode
LOCAL cAccess_token
LOCAL cToken_type
LOCAL nIssued_at
LOCAL nExpires_in
LOCAL cStatus
LOCAL cScope
LOCAL cIssuer
LOCAL cClient_id
LOCAL cApplication_name
LOCAL cApi_products
LOCAL cPublic_key

nSuccess := 0

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

oHttp := CreateObject("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

oReq := CreateObject("Chilkat.HttpRequest")
oReq:AddParam("grant_type", "client_credentials")
oReq:AddParam("client_id", "123456789")
oReq:AddParam("client_secret", "A1B2C3D4E5")
oReq:AddParam("scope", "ResourceA+ResourceB+ResourceC")

oReq:HttpVerb := "POST"
oReq:ContentType := "application/x-www-form-urlencoded"

oResp := CreateObject("Chilkat.HttpResponse")
nSuccess := oHttp:HttpReq("https://apis.usps.com/oauth2/v3/token", oReq, oResp)
IF (nSuccess == 0)
    ? oHttp:LastErrorText
    oHttp:destroy()
    oReq:destroy()
    oResp:destroy()
    RETURN
ENDIF

oSbResponseBody := CreateObject("Chilkat.StringBuilder")
oResp:GetBodySb(oSbResponseBody)

oJResp := CreateObject("Chilkat.JsonObject")
oJResp:LoadSb(oSbResponseBody)
oJResp:EmitCompact := 0

? "Response Body:"
? oJResp:Emit()

nRespStatusCode := oResp:StatusCode
? "Response Status Code = " + Str(nRespStatusCode)
IF (nRespStatusCode >= 400)
    ? "Response Header:"
    ? oResp:Header
    ? "Failed."
    oHttp:destroy()
    oReq:destroy()
    oResp:destroy()
    oSbResponseBody:destroy()
    oJResp:destroy()
    RETURN
ENDIF

//  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": "LS0tLS1CRUdJTiBQVUJMSUMgS0VZLS0tLS0KTUlJQklqQU5CZ2txaGtpRzl3MEJBUUVGQUFPQ0FROEFNSUlCQ2dLQ0FRRUF4QWxwZjNSNEE1S0lwZnhJVWk1bgpMTFByZjZVZTV3MktzeGxSVzE1UWV0UzBjWGVxaW9OT2hXbDNaaVhEWEdKT3ZuK3RoY0NWVVQ3WC9JZWYvTENZCkhUWk1kYUJOdW55VHEwT2RNZmVkUU8zYUNKZmwvUnJPTHYyaG9TRDR4U1YxRzFuTTc1RTlRYitFZ1p0cmFEUXoKNW42SXRpMUMzOHFGMjU5NVRHUWVUemx3Wk1LQng1VTY2bGwzNzlkZ2plTUJxS3ppVHZHWEpOdVg5ZzRrRlBIaApTLzNERm9FNkVFSW8zUHExeDlXTnRaSm93VkRwQUVZZTQ3SU1UdXJDN2NGcXp2d3M1b1BDRHQ4c083N2lUdDN0Cm1vK3NrM2ExWnZSaGs2WUQ3Zkt1UldQVzFEYUM4dC9pazlnWnhqQndYNlZsSUhDRzRZSHlYejZteWdGV09jMmEKOVFJREFRQUIKLS0tLS1FTkQgUFVCTElDIEtFWS0tLS0t"
//  }

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

cAccess_token := oJResp:StringOf("access_token")
cToken_type := oJResp:StringOf("token_type")
nIssued_at := oJResp:IntOf("issued_at")
nExpires_in := oJResp:IntOf("expires_in")
cStatus := oJResp:StringOf("status")
cScope := oJResp:StringOf("scope")
cIssuer := oJResp:StringOf("issuer")
cClient_id := oJResp:StringOf("client_id")
cApplication_name := oJResp:StringOf("application_name")
cApi_products := oJResp:StringOf("api_products")
cPublic_key := oJResp:StringOf("public_key")

oHttp:destroy()
oReq:destroy()
oResp:destroy()
oSbResponseBody:destroy()
oJResp:destroy()