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Lianja

USPS OAuth2 Client Credentials

See more OAuth2 Examples

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

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llSuccess = .F.

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

loHttp = createobject("CkHttp")

// 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

loReq = createobject("CkHttpRequest")
loReq.AddParam("grant_type","client_credentials")
loReq.AddParam("client_id","123456789")
loReq.AddParam("client_secret","A1B2C3D4E5")
loReq.AddParam("scope","ResourceA+ResourceB+ResourceC")

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

loResp = createobject("CkHttpResponse")
llSuccess = loHttp.HttpReq("https://apis.usps.com/oauth2/v3/token",loReq,loResp)
if (llSuccess = .F.) then
    ? loHttp.LastErrorText
    release loHttp
    release loReq
    release loResp
    return
endif

loSbResponseBody = createobject("CkStringBuilder")
loResp.GetBodySb(loSbResponseBody)

loJResp = createobject("CkJsonObject")
loJResp.LoadSb(loSbResponseBody)
loJResp.EmitCompact = .F.

? "Response Body:"
? loJResp.Emit()

lnRespStatusCode = loResp.StatusCode
? "Response Status Code = " + str(lnRespStatusCode)
if (lnRespStatusCode >= 400) then
    ? "Response Header:"
    ? loResp.Header
    ? "Failed."
    release loHttp
    release loReq
    release loResp
    release loSbResponseBody
    release loJResp
    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": "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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

lcAccess_token = loJResp.StringOf("access_token")
lcToken_type = loJResp.StringOf("token_type")
lnIssued_at = loJResp.IntOf("issued_at")
lnExpires_in = loJResp.IntOf("expires_in")
lcStatus = loJResp.StringOf("status")
lcScope = loJResp.StringOf("scope")
lcIssuer = loJResp.StringOf("issuer")
lcClient_id = loJResp.StringOf("client_id")
lcApplication_name = loJResp.StringOf("application_name")
lcApi_products = loJResp.StringOf("api_products")
lcPublic_key = loJResp.StringOf("public_key")


release loHttp
release loReq
release loResp
release loSbResponseBody
release loJResp